@article{brannan_wysocky_anderson_2024, title={Effect of Saccharomyces cerevisiae dietary supplementation (Original XPC TM ) and stocking density on production performance and egg quality in white strain hens}, volume={33}, ISSN={["1537-0437"]}, url={https://doi.org/10.1016/j.japr.2024.100423}, DOI={10.1016/j.japr.2024.100423}, abstractNote={The ongoing industry trend towards less intensive management systems is of interest to table egg producers, with antibiotic usage and stocking density being of primary concern. The present trial evaluated the effect of a Saccharomyces cerevisiae fermentation product and stocking density on hen production performance and egg quality. Eleven white egg layer strains were equally represented in cages at either high (471 cm2 per bird, HD) or low (497 cm2 per bird, LD) stocking densities. Hens were fed either a control diet (CN) or one supplemented with S. cerevisiae (Original XPCTM included at 0.68 kg/T, SC) from 17 to 41 weeks on a commercially relevant scale (70 replicates for each of the four treatments and a total of 5,740 hens). Data were collected every four weeks and analyzed in a 2 × 2 factorial design, with stocking density and diet being the main effects. Feed intake and egg production were increased in both the LD and SC groups. Improvements in egg size were also noted for SC hens, concurrent with a reduction in cracks, leaks, and vitelline elasticity. The combination of SC-LD resulted in improved hen day production, shorter time to 50% production, and increased percentage of large eggs. Overall, the main effects of SC and LD were associated with improved production performance, with larger egg size also being noted for the SC hens. The combination of SC and LD may benefit producers in achieving both production and egg size performance targets, providing an economic incentive to transition to alternative management systems.}, number={2}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Brannan, Kelly E. and Wysocky, R. and Anderson, Kenneth E.}, year={2024}, month={Jun} }
 @article{maharjan_rahimi_harding_vu_malheiros_oviedo-rondon_mian_joseph_dean_anderson_et al._2023, title={Effects of full-fat high-oleic soybean meal in layer diets on nutrient digestibility and egg quality parameters of a white laying hen strain}, volume={102}, ISSN={["1525-3171"]}, url={https://doi.org/10.1016/j.psj.2023.102486}, DOI={10.1016/j.psj.2023.102486}, abstractNote={This study was conducted to understand the impact of including full fat high-oleic soybean meal in layer hen diets on nutrient digestibility and added nutritional value in eggs. Forty-eight layers (∼36 wk old) were randomly assigned to one of 4 isonitrogenous (18.5% crude protein) treatment diets with 12 replicate birds per treatment in a 3-wk study. Treatments were 1) solvent extracted defatted soybean meal + corn diet, 2) dry extruded defatted soybean meal + corn, 3) full-fat soybean meal + corn, 4) high-oleic full-fat soybean meal + corn diet. Apparent ileal digestibility of crude fat (CF) and crude protein (CP) were determined using celite (∼2%) as an indigestible marker. Tibia strength and egg quality parameters (egg weight, shell strength, Haugh unit, shell color, and yolk color) were recorded during the study. Fatty acid profiles, including the monounsaturated fatty acid, oleic acid (C18:1, cis), in eggs and adipogenic tissue (liver, muscle, and fat pad) were measured using gas chromatography (GC-FID). Digestibility values of CF ranged from 71 to 84% and CP varied from 67 to 72% for treatment diets, with treatment mean values being no different (P > 0.05) between treatment diets. No differences between treatment diets in tibia strength or egg quality parameters (egg weight, shell strength, and Haugh unit) were observed (P > 0.05) except for yolk color. Similarly, there were no differences in the total lipids in egg yolk (P > 0.05) between treatment diets. However, oleic acid percentage of total lipid in egg and tissue was significantly higher (P < 0.001) in hens given the high-oleic full-fat soybean meal diet than in other treatment groups. No difference was observed in oleic acid percentage of total lipid in egg between the other 3 treatment diets (P > 0.05). Overall, the results exhibited that the eggs and tissue of layer hens fed the full-fat high-oleic acid soybean meal diet were higher in oleic acid while the CF and CP digestibility remained similar to the digestibility of the other diets.}, number={4}, journal={POULTRY SCIENCE}, author={Maharjan, Pramir and Rahimi, Amin and Harding, Kari L and Vu, Thien Chuong and Malheiros, Ramon and Oviedo-Rondon, Edgar O. and Mian, Rouf and Joseph, Michael and Dean, Lisa and Anderson, Kenneth E. and et al.}, year={2023}, month={Apr} }
 @article{wall_dittoe_malherios_anderson_anthony_2023, title={Evaluating the Ileal and Cecal Microbiota Composition of a 1940 Heritage Genetic Line and a 2016 Commercial Line of white Leghorns Fed Representative Diets from 1940 to 2016}, volume={13}, ISSN={["2076-3417"]}, DOI={10.3390/app132212259}, abstractNote={This study identified and evaluated differences between microbiome compositions of the ileum and ceca of 1940 and 2016 white leghorn genetic strains fed representative contemporary diets from those times. Ileal and cecal samples were collected at 69 weeks of age. Alpha and beta diversity metrics were generated, and the Analysis of Composition of Microbiomes (ANCOM) was utilized to determine significantly different taxa. Ileum and ceca alpha diversity were significantly different (p = 0.001; Q = 0.001); however, no differences between genetic lineage were observed (p > 0.05; Q > 0.05). Beta diversity between the ileum and ceca and the genetic lines was significantly different (p = 0.001; Q = 0.001). The ANCOM of the ileum showed significant differences between Proteobacteria and Actinobacteriota phyla (p ˂ 0.05) and significant differences between Pseudomonas, Rhizobiaceae, Leuconostoc, and Aeriscardovia genera (p ˂ 0.05). For ceca ANCOM, Proteobacteria, Firmicutes, Actinobacteriota, and Euryarchaeota phyla were significantly different (p ˂ 0.05), with Firmicutes having the highest relative abundance across all groups, and there were significant differences in genera Pseudomonas, Leuconostoc, Alloprevotella, and Aeri scardovia, with Alloprevotella having the highest relative abundance. The results suggest that genetic makeup in conjunction with the nutritional composition influences the cecal and ileal microbiota of corresponding hens.}, number={22}, journal={APPLIED SCIENCES-BASEL}, author={Wall, Dannica C. and Dittoe, Dana and Malherios, Ramon D. and Anderson, Kenneth E. and Anthony, Nick}, year={2023}, month={Nov} }
 @article{alig_malheiros_anderson_2023, title={Evaluation of Physical Egg Quality Parameters of Commercial Brown Laying Hens Housed in Five Production Systems}, volume={13}, ISSN={["2076-2615"]}, url={https://www.mdpi.com/2076-2615/13/4/716}, DOI={10.3390/ani13040716}, abstractNote={This study evaluates the effect of housing environment on the egg quality characteristics of brown egg layers as many different environments are currently used in the industry. Battery cages, barren colony cages, enriched colony cages, cage-free, and free-range environments were evaluated. Overall, all egg quality measurements were affected by housing environment (p < 0.01) except for vitelline membrane strength, elasticity, and egg solids. Eggshells and yolks were lightest in barren colony cages and darkest from free-range hens (p < 0.0001). Free-range eggs were heavier than eggs from all other environments (p < 0.0001). Cage-free eggs had lower albumen height and Haugh units than other environments (p < 0.0001). Lastly, cage-free and free-range eggs had stronger eggshells than the other environments (p < 0.0001), and free-range eggs had more elastic eggshells than eggs from conventional battery cages and barren colony cages (p < 0.01). Access to the range seemed to give free-range hens different nutritional advantages, which allowed for the darker yolks and shells. Furthermore, eggs from barren colony cages seemed to exhibit more negative characteristics. Simply adding enrichments to colony cages did not improve or detract from egg quality. From this research, it appears that, as the industry moves toward extensive environments, the egg quality of brown egg layers will improve.}, number={4}, journal={ANIMALS}, author={Alig, Benjamin N. and Malheiros, Ramon D. and Anderson, Kenneth E.}, year={2023}, month={Feb} }
 @article{alig_anderson_malheiros_lowery_walker_2023, title={Impact of Stocking Densities on the Microbiota of the Cloaca, Eggshell, and Egg Content of White Egg Layers in Colony Cages}, url={https://www.mdpi.com/2674-1164/2/3/31}, DOI={10.3390/poultry2030031}, abstractNote={Food safety is a major concern for commercial poultry producers and consumers. Currently, there is also pressure from retailers and legislators to increase the space per hen in cages. Five different density treatments consisting of six (208 in2/bird), nine (139 in2/bird), twelve (104 in2/bird), fifteen (83 in2/bird), and eighteen birds (69 in2/bird) per cage were examined in colony cage environments. Microbiological tests were performed at 39, 55, and 68 weeks of age. The populations of total aerobic bacteria; E. coli/coliform; Enterobacteriaceae; and yeasts and molds from an eggshell rinse, egg content, and cloacal swabs were enumerated. The prevalence of Salmonella spp. in these samples was also monitored. Overall, no bacteria were detected in any of the egg content, and there were no differences (p > 0.05) between treatments for the shell rinse. Stocking density did not influence the eggshell microbiota of the hens. Hens housed at 104 in2 per hen showed higher levels of total aerobic bacterial counts from the cloaca compared to hens at 208 in2 and 69 in2 per hen. Hens housed at 139 in2 per hen had the highest level of cloacal molds. This research demonstrates that stocking density does not influence eggshell microbiota or Salmonella contamination of the eggshell or cloaca, thereby indicating that allowing more space per hen will not positively or negatively affect the prevalence or concentration of foodborne pathogen-associated bacteria in or on the eggs.}, journal={Poultry}, author={Alig, Benjamin and Anderson, Kenneth and Malheiros, Ramon D. and Lowery, Justin and Walker, Lin}, year={2023}, month={Sep} }
 @article{garcia_anderson_guard_gast_jones_2023, title={Impact of paddock area stocking density of free-range laying hens on egg and environmental microbiology}, volume={32}, ISSN={["1537-0437"]}, url={https://doi.org/10.1016/j.japr.2023.100338}, DOI={10.1016/j.japr.2023.100338}, number={2}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Garcia, J. S. and Anderson, K. E. and Guard, J. Y. and Gast, R. K. and Jones, D. R.}, year={2023}, month={Jun}, pages={1–7} }
 @article{alig_ferket_malheiros_anderson_2023, title={The Effect of Housing Environment on Commercial Brown Egg Layer Production, USDA Grade and USDA Size Distribution}, volume={13}, ISSN={["2076-2615"]}, DOI={10.3390/ani13040694}, abstractNote={Consumer demand for retail cage-free eggs is driving the layer industry towards greater use of extensive housing environments. However, there is limited research on how these environments affect egg production characteristics of brown egg layers, as was the focus of this study. Five housing environments were evaluated under typical industry conditions, including conventional cages, enrichable colony cages, enriched colony cages, cage-free and free-range. Three different brown egg laying strains were housed in the different housing environments and managed according to standard husbandry practices and stocking densities. Data collection for the strains began at 17 weeks of age, with a base period of 28 days for feed weigh backs and egg quality assessments. Housing environment had a highly significant (p < 0.0001) effect on all egg production characteristics measured, including egg production rates (% hen-day and % hen-housed), feed consumption (g/bird/day), feed conversion (egg g/feed g), and mortality rate (%) as well as percent grade A, B, and loss. Previous research revealed better egg production metrics for white egg layers in caged environments than extensive environments. In contrast, we observed brown egg layers had optimum production results for the free-range housing environments, and the poorest performance in enrichable colony cages.}, number={4}, journal={ANIMALS}, author={Alig, Benjamin N. and Ferket, Peter R. and Malheiros, Ramon D. and Anderson, Kenneth E.}, year={2023}, month={Feb} }
 @article{alig_ferket_malheiros_anderson_2023, title={The Effect of Housing Environment on Egg Production, USDA Egg Size, and USDA Grade Distribution of Commercial White Egg Layers}, url={https://www.mdpi.com/2674-1164/2/2/17}, DOI={10.3390/poultry2020017}, abstractNote={The housing environment has become a critical issue for consumers of eggs and egg products. Therefore, it is imperative to understand how various housing environments can affect the modern laying hen. In this study, alongside the 40th NC layer performance test, four different housing environments were chosen based on industry prevalence, which include conventional cages, barren, enrichable colony cages, enriched colony cages, and cage-free environments. Hens in these environments were raised following standard feeding and lighting practices. This study found that conventional cage and enriched colony cage hens had the highest egg production level, while hens from the barren colony cages had the lowest production level. Feed efficiency followed a similar trend, where conventional cage and cage-free hens had the best feed efficiency, followed by enriched colony cage and barren colony cage hens. This study also found that conventional cage hens had the largest eggs, while cage-free hens had the smallest eggs. Cage-free and conventional cage hens had the lowest mortality rate, while hens in the barren colony cage had the highest mortality rate. From the data shown, it appears that standard, conventional cages provide white egg layers with the most optimal environment for production performance. However, a further evaluation of health and stress is needed to determine which environment provides the hen with optimal welfare.}, journal={Poultry}, author={Alig, Benjamin and Ferket, Peter R. and Malheiros, Ramon D. and Anderson, Kenneth}, year={2023}, month={Apr} }
 @article{alig_malheiros_anderson_2023, title={The Effect of Housing Environment on Physical Egg Quality of White Egg Layers}, url={https://www.mdpi.com/2674-1164/2/2/18}, DOI={10.3390/poultry2020018}, abstractNote={Currently, the egg industry is experiencing a shift in demand for eggs from cage-free environments. This study aims to evaluate the egg quality parameters of white eggs laid in several different housing environments utilized in the industry. Egg quality parameters from battery cages, barren colony cages, enriched colony cages and cage-free pens were compared. Overall, most egg quality parameters were found to be different across housing environments. Battery cages produced the heaviest eggs and eggs with the highest Haugh unit (p < 0.05). Cage-free hens produced eggs with the darkest yolks, lowest Haugh units, strongest shells and highest solids percentage compared to other environments (p < 0.05). This study did not detect differences between any housing environment in shell color, shell elasticity, vitelline membrane strength or vitelline membrane elasticity (p > 0.05). Moreover, this study did not detect any differences in egg quality parameters between enriched and barren colony cages (p > 0.05). It appears that white egg-laying hens had superior egg quality performance in caged environments and that cage-free pens only improved yolk color. Furthermore, it appears that simply adding enrichments to cages does not affect any egg quality parameters. From the results of our study, we believe that current intensive environments, such as cages, are the most beneficial for white egg layer egg quality and that as the industry moves toward cage-free, new strategies will need to be developed to preserve egg quality. More research is needed, particularly evaluating free-range environments.}, journal={Poultry}, author={Alig, Benjamin and Malheiros, Ramon D. and Anderson, Kenneth}, year={2023}, month={Apr} }
 @article{malheiros_moraes_anderson_castro_ferrel_2022, title={Influence of dietary dacitic tuff breccia on laying hen performance and egg quality parameters and bone structure at 85 weeks of age after a non-anorexic molt program at 73 to 77 weeks}, volume={101}, ISSN={["1525-3171"]}, url={https://doi.org/10.1016/j.psj.2022.101718}, DOI={10.1016/j.psj.2022.101718}, abstractNote={The objective of the study was to assess the efficacy of AZOMITE (AZM), a dacitic tuff breccia, in laying hens through egg quality and production parameters. A total of ninety six 73-wk-old Hy-Line W-36 commercial laying hens were randomly assigned to 2 dietary treatments, a control diet and the same diet containing 0.25% AZM, with 24 replicates of 2 hens/replication. From 73 to 77 wk, hens went through nonanorexic molt, and, from 77 to 85 wk, the hens were evaluated for egg production, eggshell quality, and bone health. At wk 85, tibiotarsi were collected for ash and mineral composition, ileal contents were collected for calcium, phosphorus, apparent metabolizable energy corrected for N (AMEn), and apparent nitrogen retention (ANR) evaluation. AZM-fed hens tended to have higher body weight (P = 0.07) from 82 to 83 and 84 to 85 wk, and higher hen day egg production than control (90.54 vs. 79.51%, P = 0.005) from 84 to 85 wk. In general, no differences were reported in feed intake, eggshell color, egg weight, albumen height, Haugh units, or eggshell thickness (P > 0.05). However, shell strength and elasticity were improved (P < 0.02) and yolk color was decreased (P = 0.03) in AZM-fed hens than control. Moreover, the digestibility of Ca, AMEn, and ANR was increased with 0.25% AZM compared to control (P < 0.01). Tibiotarsi P and Ca percentage were lower in AZM-fed birds than control (P < 0.01), without affecting bone strength and mineral density (P > 0.36). Therefore, the use of 0.25% AZM showed a potential in improving egg production and eggshell strength, while maintaining bone quality in post-molt laying hens.}, number={4}, journal={POULTRY SCIENCE}, author={Malheiros, R. D. and Moraes, V. M. B. and Anderson, K. E. and Castro, F. L. S. and Ferrel, J. E.}, year={2022}, month={Apr} }
 @article{gast_jones_guraya_anderson_karcher_2021, title={Applied Research Note: Internal organ colonization and horizontal transmission of experimental Salmonella Enteritidis and Salmonella Kentucky infection in vaccinated laying hens in indoor cage-free housing}, volume={30}, ISSN={["1537-0437"]}, DOI={10.1016/j.japr.2020.100132}, abstractNote={Cage-free housing of laying hens may provide opportunities for widespread environmental distribution of Salmonella contamination and horizontal transmission of infection within flocks. Salmonella Enteritidis in commercial laying flocks presents an ongoing public health concern because reproductive organ colonization in hens leads to deposition inside eggs. Many S. Enteritidis control programs include vaccination to induce protective immunity against infection. Salmonella Kentucky is common in egg production environments but has not been associated with egg contamination. This study compared the invasion of internal organs and horizontal spread of infection during the first 2 wk after experimental S. Enteritidis and S. Kentucky infection of previously vaccinated laying hens in indoor cage-free housing. Two groups of 72 hens each were housed in isolation rooms simulating commercial cage-free barns and 1/3 of the hens were orally inoculated with either S. Enteritidis (1 room) or S. Kentucky (1 room). At 6 and 12 d after inoculation, half of the hens in each room were euthanized and samples of the liver, spleen, ovary, oviduct, and intestinal tract were removed for bacteriologic culturing. Among hens inoculated with S. Enteritidis, 66.7% of the intestinal, liver, and spleen samples were positive for the pathogen at 6 d after infection, as well as 41.7% of intestines and 16.7% of livers from contact-exposed hens. Significantly (P < 0.05) fewer hens were colonized by S. Kentucky. These results demonstrate that vaccines may not always provide complete exclusion of Salmonella. In cage-free housing systems, vaccination should be supplemented with a comprehensive risk reduction effort to prevent extensive horizontal dissemination of Salmonella.}, number={1}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Gast, Richard K. and Jones, Deana R. and Guraya, Rupa and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2021}, month={Mar} }
 @article{brannan_anderson_2021, title={Examination of the impact of range, cage-free, modified systems, and conventional cage environments on the labor inputs committed to bird care for three brown egg layer strains}, volume={30}, ISSN={["1537-0437"]}, DOI={10.1016/j.japr.2020.100118}, abstractNote={Although the poultry industry has developed into an intensive management system over the past several decades, current trends are moving toward extensive systems with decreased hen-stocking density. However, there is limited information on the resource demands of such systems, particularly with regards to labor requirements. Labor h commitment per hen originally housed and hens surviving were evaluated for 4 different environments: range, cage-free, modified cage, and conventional cage. Within each system, 3 strains of brown egg layers were examined to determine whether production system influenced labor h. Data collection began at 33 wk of age and continued until 89 wk in all environments. Range systems demonstrated the highest labor h requirement for both the hens originally housed and hens surviving measurements, particularly during the summer months when pasture management within the paddocks was time consuming. Conventional and modified cage systems required the least time commitment with cage-free serving as an intermediate. Cage-free labor h increased toward the end of the cycle as maintaining litter quality within the house became more demanding. The cost of labor h was not offset by the price per dozen eggs produced, and the difference was greater in the extensive systems. This study supports previous findings that extensive layer production systems require greater labor h and provides an economic perspective to the increased time commitment.}, number={1}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Brannan, Kelly E. and Anderson, Kenneth E.}, year={2021}, month={Mar} }
 @article{toomer_vu_sanders_redhead_malheiros_anderson_2021, title={Feeding Laying Hens a Diet Containing High-Oleic Peanuts or Oleic Acid Enriches Yolk Color and Beta-Carotene While Reducing the Saturated Fatty Acid Content in Eggs}, volume={11}, ISSN={["2077-0472"]}, DOI={10.3390/agriculture11080771}, abstractNote={We investigated the dietary effects of high-oleic peanuts (HOPN) or oleic fatty acids (OA) on older production hen performance, egg mass and quality, and lipid composition. A total of 99 laying hens were divided between three treatments and fed ad libitum for 8 weeks: (1) Conventional diet; (2) HOPN diet; (3) OA diet. Body weight (BW) was measured at weeks 1 and 8, and feed, egg weights (EW), and egg quality parameters were collected. Data was analyzed by analysis of variance at p < 0.05 significance level. There were no treatment differences in 8 week BW, feed conversion ratio, or average weekly egg quality parameters. The 8 week average EW of eggs from the HOPN group had reduced EW relative to the other treatment groups (p = 0.0004). The 8-week average yolk color score (p < 0.0001) was greater in eggs from the HOPN group relative to the other treatments. Overall, the β-carotene (p < 0.006) and OA content (p < 0.0001) was greater in eggs from the HOPN group, with reduced saturated fats in eggs from the HOPN group relative to the other treatments. These results suggest that HOPN and/or OA may be a useful layer feed ingredient to enrich eggs, while significantly reducing egg size in older production hens.}, number={8}, journal={AGRICULTURE-BASEL}, author={Toomer, Ondulla T. and Vu, Thien Chuong and Sanders, Elliot and Redhead, Adam Karl and Malheiros, Ramon and Anderson, Kenneth E.}, year={2021}, month={Aug} }
 @article{garcia_anderson_guard_gast_jones_2021, title={Impact of organic dairy cattle manure on environmental and egg microbiology of organic free-range laying hens}, volume={30}, ISSN={["1537-0437"]}, DOI={10.1016/j.japr.2021.100189}, abstractNote={The popularity of free-range and organic poultry has increased in recent years due to consumer demands. A study was conducted to evaluate how the presence of organic dairy cattle manure could influence the environmental and egg microbiology of organic free-range laying flocks. A flock of brown egg layers was split and maintained in a rotational paddock grazing schedule of which was free of or exposed to organic dairy manure. Environmental and egg sampling occurred approximately every 8 wk between 20 and 44 wk of age for a presence of Listeria spp., Campylobacter spp., Salmonella spp., and enumeration of Enterobacteriaceae. There was no significant difference in the occurrence of Listeria spp., Campylobacter spp. and Salmonella spp. in environmental and egg samples between integrated and control grazing organic free-range flocks. A random sampling of Enterobacteriaceae colonies produced 211 viable isolates for biochemical identification. Seventeen genera, species, or serotypes were identified. There was a greater (P < 0.05) prevalence of total coliforms found on shell emulsion, egg contents, nest box straw, and forage samples from integrated organic free-range compared to control organic free-range flocks. Seasons of the year impacted microbial levels recovered from environmental and egg samples, with which summer having the highest level of all populations monitored. Additional studies are needed to fully understand the effect of mixed production rotational grazing on the prevalence of pathogens and Enterobacteriaceae on organic nest-run eggs and the grazing environment.}, number={4}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Garcia, J. S. and Anderson, K. E. and Guard, J. Y. and Gast, R. K. and Jones, D. R.}, year={2021}, month={Dec} }
 @article{gast_jones_guraya_anderson_karcher_2021, title={Research Note: Contamination of eggs by Salmonella Enteritidis and Salmonella Typhimurium in experimentally infected laying hens in indoor cage-free housing}, volume={100}, ISSN={["1525-3171"]}, url={https://doi.org/10.1016/j.psj.2021.101438}, DOI={10.1016/j.psj.2021.101438}, abstractNote={Contaminated eggs are a leading source of human Salmonella infections and this problem continues to challenge public health authorities and egg industries around the world. Salmonella invasion of the ovaries and oviducts of infected laying hens can result in bacterial deposition inside the edible portions of developing eggs. The introduction, persistence, and transmission of salmonellae in commercial egg-laying flocks are influenced by flock management practices, but the food safety ramifications of different types of laying hen housing remain unresolved. The present study assessed the frequency of internal contamination of eggs after experimental Salmonella Enteritidis and S. Typhimurium infection of laying hens in indoor cage-free housing. Groups of 72 hens were housed on wood shavings in isolation rooms simulating commercial cage-free barns with community kick-out nest boxes and perches and 1/3 of the hens in each room were orally inoculated with 8.0 × 107 cfu of 2-strain mixtures of either S. Enteritidis (2 rooms) or S. Typhimurium (2 rooms), and the entire internal contents of all eggs laid 5 to 30 d postinoculation in nest boxes or on the flooring substrate were cultured to detect Salmonella. Contaminated eggs were laid between 8 and 28 d postinoculation. The overall incidence of S. Enteritidis isolation from eggs (3.41%) was significantly (P = 0.0005) greater than S. Typhimurium (1.19%). The contamination frequencies associated with the 2 egg collection locations were not significantly different (P > 0.05). These results demonstrate that oral infection of a relatively small proportion of laying hens in indoor cage-free housing with invasive Salmonella serovars can result in the production of internally contaminated eggs at low frequencies over a period of nearly a month postinoculation.}, number={11}, journal={POULTRY SCIENCE}, author={Gast, Richard K. and Jones, Deana R. and Guraya, Rupa and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2021}, month={Nov} }
 @article{toomer_vu_wysocky_moraes_malheiros_anderson_2021, title={The Effect of Feeding Hens a Peanut Skin-Containing Diet on Hen Performance, and Shell Egg Quality and Lipid Chemistry}, volume={11}, ISSN={["2077-0472"]}, DOI={10.3390/agriculture11090894}, abstractNote={Peanut skins are a considerable waste product with little current economic value or use. We aimed to determine the dietary effects of peanut skins on layer production performance and egg quality and chemistry of the eggs produced. Two hundred commercial hens were randomly assigned to four treatments (five replicates) and fed ad libitum for 8 weeks: conventional control diet, diet containing 24% high-oleic peanut (HOPN), diet containing 3% peanut skin (PN Skin), and a diet with 2.5% oleic acid (OA). Hens fed the HOPN diet had significantly reduced body weights relative to the control and PN Skin treatments, producing fewer total eggs over the 8-week experimental period. Eggs weights were similar between the control and PN Skin treatments at weeks 2 and 4, while eggs from the PN Skin treatment group were heavier than other treatments at weeks 6 and 8 of the experiment. Eggs produced from the HOPN treatment had reduced saturated fatty acid (FA) content in comparison to the other treatment groups, while similar between PN Skin and control eggs at week 8 of the experiment. This study suggests that PN skins may be a suitable alternative layer feed ingredient.}, number={9}, journal={AGRICULTURE-BASEL}, author={Toomer, Ondulla and Vu, Thien and Wysocky, Rebecca and Moraes, Vera and Malheiros, Ramon and Anderson, Kenneth}, year={2021}, month={Sep} }
 @article{harding_vu_wysocky_malheiros_anderson_toomer_2021, title={The Effects of Feeding a Whole-in-Shell Peanut-Containing Diet on Layer Performance and the Quality and Chemistry of Eggs Produced}, volume={11}, ISSN={["2077-0472"]}, DOI={10.3390/agriculture11111176}, abstractNote={The abundance of peanut and poultry production within the state of North Carolina and the US Southeast, led us to conduct a layer feeding trial to determine the utilization of whole-in-shell high-oleic peanuts (WPN) and/or unblanched high-oleic peanuts (HOPN) as an alternative feed ingredient for poultry. To meet this objective, we randomly assigned 576 shaver hens to 4 dietary treatments (4 rep/trt). The dietary treatments consisted of a conventional control diet (C1), a diet containing 4% WPN, an 8% HOPN diet, and a control diet containing soy protein isolate (C2). Feed and water were provided for 6 weeks ad libitum. Pen body weights (BW) were recorded at week 0 and week 6 (wk6), and feed weights were recorded bi-weekly. Shell eggs were collected daily and enumerated. Bi-weekly 120 eggs/treatment were collected for quality assessment and egg weight (EW), while 16 eggs/treatment were collected for chemical analysis. There were no significant differences in BW or EW at week 6. Hens fed the C2 produced more total dozen eggs relative to C1 hens over the feeding trial (p < 0.05). Hens fed the C1 diet consumed less total feed relative to the other treatments with the best feed conversion ratio (p < 0.05). Most eggs produced from each treatment were USDA grade A, large eggs. There were no differences in egg quality, with the exception of yolk color, with significantly higher yolk color scores in eggs produced from the C1 and C2 treatments relative to the other treatments (p < 0.05). Eggs produced from the HOPN treatment had significantly reduced stearic and linoleic fatty acid levels relative to the other treatments (p < 0.05). Eggs produced from hens fed the WPN diet had significantly greater β-carotene content relative to eggs from the other treatment groups (p < 0.05). In summary, this study suggests that WPN and/or HOPN may be a suitable alternative layer feed ingredient and a dietary means to enrich the eggs produced while not adversely affecting hen performance.}, number={11}, journal={AGRICULTURE-BASEL}, author={Harding, Kari L. and Vu, Thien and Wysocky, Rebecca and Malheiros, Ramon and Anderson, Kenneth E. and Toomer, Ondulla T.}, year={2021}, month={Nov} }
 @article{redhead_sanders_vu_malheiros_anderson_toomer_2021, title={The effects of high-oleic peanuts as an alternate feed ingredient on performance, ileal digestibility, apparent metabolizable energy, and histology of the small intestine in laying hens}, volume={5}, ISSN={["2573-2102"]}, DOI={10.1093/tas/txab015}, abstractNote={Abstract}, number={1}, journal={TRANSLATIONAL ANIMAL SCIENCE}, author={Redhead, Adam K. and Sanders, Elliot and Vu, Thien C. and Malheiros, Ramon D. and Anderson, Kenneth E. and Toomer, Ondulla T.}, year={2021}, month={Jan} }
 @article{bartz_anderson_oviedo-rondon_livingtson_grimes_2020, title={Effects of stocking density on large white, commercial tom turkeys reared to 20 weeks of age: 1. growth and performance}, volume={99}, ISSN={["1525-3171"]}, DOI={10.1016/j.psj.2020.08.024}, abstractNote={Industry standards for turkey stocking densities are variable and may not represent the more rapidly growing strains currently available. Therefore, a study was completed to evaluate 4 stocking densities: a nominal density (0.3525 m2/bird), 10% tighter density (0.3169 m2/bird), 10% looser density (0.3882 m2/bird), and 20% looser density (0.4238 m2/bird) on the effects on large white, commercial male turkeys with regard to performance from 5 to 20 wk of age. Brooding stocking density was fixed for all pens of birds with 60 birds per replicate pen at 0.46 m2/bird to 5 wk of age. Density treatments were applied from 5 to 20 wk by altering pen size with pen population held constant at 60 per pen. There were 4 pens of birds per density treatment. Birds were weighed individually at 0, 5, and 20 wk of age and performance parameters were calculated. There were no differences in bird performance at 5 wk, which was expected because stocking density was fixed. From 5 to 20 wk and at 20 wk, birds that were reared at the nominal standard (0.3525 m2/bird) and 10% tighter density (0.3169 m2/bird) had significantly lower body weight compared with the 10% looser density (0.3882 m2/bird) and 20% looser density (0.4238 m2/bird) (P = 0.03 and 0.01, respectfully). The feed conversion ratio (FCR) tended (P = 0.08) to be improved for birds reared at looser density. In addition, based on linear regression, as stocking density decreased (i.e., m2/bird increased), BW (P < 0.05) increased, and FCR (P = 0.10) tended to decrease (improve) at 20 wk. It was concluded that birds reared at looser density had improved performance.}, number={11}, journal={POULTRY SCIENCE}, author={Bartz, B. M. and Anderson, K. A. and Oviedo-Rondon, E. O. and Livingtson, K. and Grimes, J. L.}, year={2020}, month={Nov}, pages={5582–5586} }
 @article{beckstead_anderson_mcdougald_2020, title={Oviduct Fluke (Prosthogonimus macrorchis) Found Inside a Chicken Egg in North Carolina}, volume={64}, ISSN={["1938-4351"]}, DOI={10.1637/aviandiseases-D-20-00021.s1}, number={3}, journal={AVIAN DISEASES}, author={Beckstead, R. B. and Anderson, K. and McDougald, L. R.}, year={2020}, month={Sep}, pages={352–353} }
 @article{jones_gast_regmi_ward_anderson_karcher_2020, title={Pooling of Laying Hen Environmental Swabs and Efficacy of Salmonella Detection}, volume={83}, ISSN={["1944-9097"]}, DOI={10.4315/JFP-19-467}, abstractNote={Environmental testing for  Salmonella  Enteritidis is required for U.S. shell egg producers with > 3,000 hens on a farm. The egg producer assumes all costs for the mandatory testing. According to the FDA Egg Rule, either manure scraper or drag swabs can be collected according to published guidelines and requirements. The current study was undertaken to determine the efficacy of  Salmonella  detection in single, two, and four swab pools of either manure scraper or drag swabs. Resistant isolates of  Salmonella  Enteritidis (1000 ppm streptomycin; SE), Heidelberg (200 ppm nalidixic acid (NA); SH), Typhimurium (200 ppm NA; ST), and Kentucky (200 ppm NA; SK) were utilized. Low (approximately 8.4 CFU) and high (approximately 84 CFU) dose inocula were introduced onto a single swab within a pool. A single flock of each conventional cage (manure scraper swabs) and cage-free barn (drag swabs) were monitored throughout the study at the ages required under the FDA Egg Rule. The greatest and most consistent recovery of inoculum was found in single swab samples. For low dose inocula, it was difficult to recover isolates from single manure scraper swabs (57.9 - 29.2 %) and decreased as more swabs were added to the pool. Recovery of isolates in manure scraper swabs was greater for high dose inoculum, though SH exhibited difficulty competing with naturally occurring flora. One and two swab pools of drag swabs had similar rates of recovery at both low and high dose SE, SH, and ST. When SE and SK were combined in an inoculum, SE was recovered at a much higher rate than SK for all types of swabs and doses of inocula. Pooling of two drag swabs allowed for similar detection of low and high dose  Salmonella  tested in the current study, but the pooling of manure scraper swabs decreased detection of low dose  Salmonella .}, number={6}, journal={JOURNAL OF FOOD PROTECTION}, author={Jones, Deana R. and Gast, Richard K. and Regmi, Prafulla and Ward, Garrett E. and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2020}, month={Jun}, pages={943–950} }
 @article{toomer_sanders_vu_livingston_wall_malheiros_carvalho_livingston_ferket_anderson_2020, title={Potential Transfer of Peanut and/or Soy Proteins from Poultry Feed to the Meat and/or Eggs Produced}, volume={5}, ISSN={2470-1343 2470-1343}, url={http://dx.doi.org/10.1021/acsomega.9b03218}, DOI={10.1021/acsomega.9b03218}, abstractNote={Previous studies have demonstrated that allergenic feed proteins from peanuts in the diets of layer hens are not detected in the eggs produced. Hence, in this study, we aimed to determine if soy and/or peanut proteins in poultry feed rations of broiler chickens or layer hens would be transferred or detectable in the meat or eggs produced. To meet this objective, 99 layer hens and 300 broiler chickens were equally divided into treatment groups and fed one of three experimental diets: control soybean meal and corn diet, whole unblanched high-oleic peanut and corn diet (HO PN), or a control diet spiked supplemented with oleic acid (OA) oil. At termination, broiler chickens were processed, and chicken breast samples of the left pectoralis muscle were collected, and eggs were collected from layers. Total protein extracts from pooled egg samples and chicken breast samples were subjected to enzyme-linked immunosorbent assay (ELISA) methods and immunoblotting analysis with rabbit antipeanut agglutinin antibodies and rabbit antisoy antibodies for the detection of peanut and soy proteins. Peanut and soy proteins were undetected in all pooled egg samples and individual chicken breast meat samples using immunoblotting techniques with rabbit antipeanut agglutinin and rabbit antisoy antibodies. Moreover, quantitative ELISA allergen detection methods determined all pooled egg samples and individual meat samples as “not containing” peanut or soy allergens. Therefore, this study helps to evaluate the risk associated with the potential transfer of allergenic proteins from animal feed to the products produced for human consumption.}, number={2}, journal={ACS Omega}, publisher={American Chemical Society (ACS)}, author={Toomer, Ondulla T. and Sanders, Elliot and Vu, Thien C. and Livingston, Matthew L. and Wall, Brittany and Malheiros, Ramon D. and Carvalho, Luiz Victor and Livingston, Kim A. and Ferket, Peter R. and Anderson, Kenneth E.}, year={2020}, month={Jan}, pages={1080–1085} }
 @article{gast_jones_guraya_anderson_karcher_2020, title={Research Note: Horizontal transmission and internal organ colonization by Salmonella Enteritidis and Salmonella Kentucky in experimentally infected laying hens in indoor cage-free housing}, volume={99}, ISSN={["1525-3171"]}, DOI={10.1016/j.psj.2020.08.006}, abstractNote={The transmission of Salmonella to humans via contaminated eggs is an international public health concern. S. Enteritidis is deposited inside eggs after colonizing reproductive tissues of infected hens. Diverse housing facility characteristics and flock management practices influence Salmonella persistence and transmission in poultry, but the food safety consequences of different housing systems for laying hens remain unresolved. The present study compared the horizontal transmission of infection and invasion of internal organs during the first 2 wk after experimental S. Enteritidis and S. Kentucky infection of laying hens in indoor cage-free housing. Groups of 72 hens were housed in isolation rooms simulating commercial cage-free barns, and 1/3 of the hens in each room were orally inoculated with either S. Enteritidis (2 rooms) or S. Kentucky (2 rooms). At 6 d and 12 d postinoculation, 12 inoculated and 24 contact-exposed hens in each room were euthanized, and samples of liver, spleen, ovary, oviduct, and intestinal tract were removed for bacteriologic culturing. All orally inoculated hens were positive for intestinal colonization by S. Enteritidis at 6 d postinfection, and 70.8% of contact-exposed hens had become colonized by 12 d. S. Enteritidis was isolated from 100% of livers and 50.0% of ovaries from inoculated birds at 6 d and from 41.7% of livers and 10.4% of ovaries from contact-exposed birds at 12 d. The majority of both orally inoculated and contact-exposed hens were positive for intestinal colonization by S. Kentucky at 6 d, but S. Kentucky was found in other internal organs of both inoculated and contact-exposed hens significantly (P < 0.05) less often than S. Enteritidis at both sampling intervals. These results indicate that Salmonella infection can spread rapidly and extensively among hens in cage-free indoor housing, including a high frequency of internal organ involvement for invasive S. Enteritidis.}, number={11}, journal={POULTRY SCIENCE}, author={Gast, Richard K. and Jones, Deana R. and Guraya, Rupa and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2020}, month={Nov}, pages={6071–6074} }
 @article{sigmon_malheiros_anderson_payne_beckstead_2019, title={Blackhead Disease: Recovery of Layer Flock After Disease Challenge}, volume={28}, ISSN={1056-6171}, url={http://dx.doi.org/10.3382/japr/pfz029}, DOI={10.3382/japr/pfz029}, abstractNote={SUMMARY Blackhead disease, caused by the protozoan Histomonas meleagridis, is commonly found in layer pullets raised on the floor. We examined the effects of blackhead disease during the pullet-rearing period and on subsequent productivity during the first 8 wk of the laying cycle. Treatments were (1) uninfected controls and (2) H. meleagridis -infected pullets, with 4 replicate pens/treatment, 32 pullets/pen (Hy-LineW-36). Pullets in the challenge treatment were infected with H. meleagridis on day 18. Four birds/pen were necropsied on days 23 and 28 for lesion scores and day 176 for detection of H. meleagridis. Hens were moved to individual layer cages on day 120 and observed daily for feed consumption, date of first lay and egg production parameters. Pullets were positive for signs of blackhead disease in 83%–90% of infected birds necropsied on days 23 and 28, with average cecal lesion scores of 2.5 and 2.9. No liver lesions were observed. On day 176, 40% of infected birds were positive for H. meleagridis in the ceca. During the laying cycle, there were no significant differences (P ≤ 0.05) between treatments in terms of date of first lay, hen-day egg production, egg weight, feed conversion, egg mass/hen, or other reproduction measurements. These results showed that while there was no long-term effect of blackhead infection on layer productivity under laboratory conditions, H. meleagridis persisted in the flock, providing a reservoir for infection.}, number={3}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Sigmon, C.S. and Malheiros, R.D. and Anderson, K.E. and Payne, J.A. and Beckstead, R.B.}, year={2019}, month={Sep}, pages={755–760} }
 @article{gast_regmi_guraya_jones_anderson_karcher_2019, title={Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens of four commercial genetic lines in conventional cages and enriched colony housing}, volume={98}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pey541}, DOI={10.3382/ps/pey541}, abstractNote={ABSTRACT The prevalence of Salmonella Enteritidis in commercial egg‐laying flocks is a prominent public health concern because contaminated eggs cause human illness. Deposition of this pathogen inside eggs results from bacterial colonization of reproductive tissues in infected hens. Environmental conditions can influence avian Salmonella infections, but the food safety consequences of different poultry housing systems remain uncertain. The present study assessed the invasion of internal organs by Salmonella Enteritidis in groups of experimentally infected laying hens of four commercial genetic lines (designated as white egg lines W1 and W2 and brown egg lines B1 and B2). Groups of hens from each line were housed at 555 cm2 of floor space per bird in both conventional cages and colony units enriched with access to perches and nesting areas. All hens were orally inoculated with 5.75 × 107 colony‐forming units of a two‐strain Salmonella Enteritidis mixture. At 6 to 7 d post‐inoculation, hens were euthanized, and samples of liver, spleen, ovary, oviduct, and intestinal tract were removed for bacteriologic culturing. The frequency of Salmonella Enteritidis recovery from intestinal samples was significantly (P < 0.05) greater for the two white egg lines combined than for the two brown egg lines combined in both conventional cage (72.2% vs. 50.0%) and enriched colony housing systems (66.7% vs. 37.5%). The frequency of intestinal Salmonella Enteritidis isolation from line B1 was significantly higher from hens in conventional cages (47.2%) than in enriched colonies (22.2%), but no differences were observed for other hen lines. Line W1 yielded more positive intestinal samples than either brown egg line in conventional cages, and line B2 had fewer positive intestinal samples than all other lines in enriched colonies. There were no significant differences between hen lines or housing systems in Salmonella Enteritidis isolation from other internal organs. These results demonstrate that Salmonella Enteritidis colonization of the intestinal tract can vary between genetic lines of egg‐laying hens and that some lines are subject to housing system influences on Salmonella susceptibility.}, number={4}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K and Regmi, Prafulla and Guraya, Rupa and Jones, Deana R and Anderson, Kenneth E and Karcher, Darrin M}, year={2019}, month={Apr}, pages={1785–1790} }
 @article{gast_regmi_guraya_jones_anderson_karcher_2019, title={Contamination of eggs by Salmonella Enteritidis in experimentally infected laying hens of four commercial genetic lines in conventional cages and enriched colony housing}, volume={98}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pez222}, DOI={10.3382/ps/pez222}, abstractNote={Human illness caused by the consumption of eggs contaminated with Salmonella Enteritidis is a continuing international public health concern. This pathogen is deposited inside the edible contents of eggs as a consequence of its ability to colonize reproductive tissues in infected hens. Conditions in the housing environment can influence the persistence and transmission of avian Salmonella infections, but the food safety ramifications of different poultry management systems are not entirely clear. The present study assessed the deposition of S. Enteritidis inside eggs laid by groups of experimentally infected laying hens of 4 commercial genetic lines (designated as white egg lines W1 and W2 and brown egg lines B1 and B2). Groups of hens from each line were housed at 555 cm2 of floor space per bird in both conventional cages and colony units enriched with access to perches and nesting areas. All hens were orally inoculated with 5.75 × 107 cfu of a 2-strain S. Enteritidis mixture, and the internal contents of eggs laid 5 to 24 D post-inoculation were cultured to detect the pathogen. No significant differences in egg contamination frequencies were found between the 2 housing systems for any of the hen lines. Contaminated eggs were laid between 7 and 21 D post-inoculation at an overall frequency of 2.47%, ranging from 0.25 to 4.38% for the 4 hen lines. The frequency of S. Enteritidis recovery from egg samples was significantly (P < 0.05) lower for line B2 than for any of the other lines, and the egg contamination frequency for line W1 was significantly greater than for line W2. The overall incidence of contamination among white eggs (3.38%) was significantly higher than among brown eggs (1.56%). These results demonstrate that S. Enteritidis deposition inside eggs can vary between genetic lines of infected laying hens, but housing these hens in 2 different systems did not affect the production of contaminated eggs.}, number={10}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K and Regmi, Prafulla and Guraya, Rupa and Jones, Deana R and Anderson, Kenneth E and Karcher, Darrin M}, year={2019}, month={Oct}, pages={5023–5027} }
 @article{toomer_hulse-kemp_dean_boykin_malheiros_anderson_2019, title={Feeding high-oleic peanuts to layer hens enhances egg yolk color and oleic fatty acid content in shell eggs}, volume={98}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pey531}, DOI={10.3382/ps/pey531}, abstractNote={ABSTRACT Previous studies have identified normal‐oleic peanuts as a suitable and economical broiler feed ingredient. However, no studies to date have examined the use of high‐oleic (HO) peanut cultivars as a feed ingredient for laying hens and determined the impact of feeding HO peanuts on performance and egg nutritive qualities. This project aimed to examine the use of HO peanuts as a feed ingredient for layer hens to determine the effect on performance, egg lipid chemistry, and quality of the eggs produced. Forty‐eight 40‐wk‐old layer hens were fed a conventional soybean meal + corn control diet or a HO peanut + corn diet for 10 wk in conventional battery cages. Body and feed weights were collected weekly. Pooled egg samples were analyzed for quality, lipid analysis, and peanut protein allergenicity. There were no significant differences in hen performance or egg quality as measured by USDA grade quality, egg albumen height, or egg Haugh unit between the treatment groups. However, eggs produced from layer hens fed the HO peanut + corn diet had reduced egg weights relative to the controls (P = 0.0001). Eggs produced from layer hens fed the HO peanut diet had greater yolk color scores (P < 0.0001), HO fatty acid (P < 0.0001), and &bgr;‐carotene (P < 0.0001) levels in comparison to the controls. Eggs produced from hens fed the control diet had greater palmitic and stearic saturated fatty acids (P < 0.0001), and trans fat (P < 0.0001) content compared to eggs produced from hens fed the HO peanut diet. All egg protein extracts from all treatments at each time point were non‐reactive with rabbit anti‐peanut agglutinin antibodies. This study identifies HO peanuts as an abundant commodity that could be used to support local agricultural markets of peanuts and poultry within the southeastern United States and be of economic advantage to producers while providing a potential health benefit to the consumer with improved egg nutrition.}, number={4}, journal={Poultry Science}, publisher={Elsevier BV}, author={Toomer, Ondulla T and Hulse-Kemp, Amanda M and Dean, Lisa L and Boykin, Deborah L and Malheiros, Ramon and Anderson, Kenneth E}, year={2019}, month={Apr}, pages={1732–1748} }
 @article{kidd_anderson_2019, title={Laying hens in the U.S. market: An appraisal of trends from the beginning of the 20th century to present}, volume={28}, ISSN={1056-6171}, url={http://dx.doi.org/10.3382/japr/pfz043}, DOI={10.3382/japr/pfz043}, abstractNote={SUMMARY This typescript has been written to provide a brief history of the commercial egg industry and the modern laying hen from the beginning of the 20th century to present. Certainly the hens’ husbandry and production practices will continue to change at the onset of this publication and thereafter. Farmers, egg distribution centers, and commercial egg companies in the U.S. have done an excellent job in keeping eggs affordable and in plentiful supply during the cited 100 yr plus (e.g., 1900 to present) of population growth, urban and suburban growth, and declining egg farmers and producers. Further, as industry efficiency and company consolidation increased, so did hen rearing practice misconceptions among U.S. consumers. The 2010 U.S. Census indicates that 1.6% of the US population is engaged in agriculture production, which feeds the remaining 98.4% of the population. This review highlights over 100 yr of table egg production in the U.S., beginning in 1900 when approximately 25% of the U.S. population was engaged in agriculture production.}, number={4}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Kidd, M.T. and Anderson, K.E.}, year={2019}, month={Dec}, pages={771–784} }
 @article{eberle-krish_jones_gast_robison_anderson_karcher_2019, title={Microbiological Impact of Delayed Movement of Pullets}, volume={28}, ISSN={1056-6171}, url={http://dx.doi.org/10.3382/japr/pfy074}, DOI={10.3382/japr/pfy074}, abstractNote={SUMMARY The depopulation of healthy birds during a disease outbreak can impact recovery and further disrupt the food supply. In 2015, the United States faced one of the largest outbreaks of highly pathogenic avian influenza ever confirmed. Many of the 7 million pullets depopulated were healthy but could not be moved to laying facilities because of their location in quarantine zones. The objective of this study was to assess the impact of an early production induced molt on Salmonella and Campylobacter prevalence, as well as total aerobes and Enterobacteriaceae enumeration. Pullets were reared in a cage-free barn from 0 to 16 wk. At 17 wk, pullets were assigned to 1 of 4 treatments: control (AV), floor (FL), enrichment (EN), and molt (MT). AV was moved into an aviary system to begin lay, while FL, EN, and MT were brought into lay in the barn. When production reached 10%, a non-feed withdrawal diet was given to MT for 6 wk. Post-molt, all remaining treatments were moved to the aviary and maintained until 32 wk. Fecal, organ, and egg shell samples were collected and analyzed at the onset of lay, pre-molt, post-molt, and at depopulation to determine prevalence of Salmonella and Campylobacter. Total aerobic and Enterobacteriaceae loads were enumerated for egg shells collected from the litter, nest box, and aviary system wire. There was no difference for Salmonella and Campylobacter prevalence among treatments for all samples. While no difference was found in total aerobe plate counts pre-molt, there was a difference (P}, number={2}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Eberle-Krish, KristaN. and Jones, DeanaR. and Gast, RichardK. and Robison, CaraI. and Anderson, KennethE. and Karcher, DarrinM.}, year={2019}, month={Jun}, pages={318–328} }
 @article{karcher_jones_robison_eberle_gast_anderson_2019, title={Production and Well-Being Resulting From Delayed Movement of Pullets to the Hen Facility}, volume={28}, ISSN={1056-6171}, url={http://dx.doi.org/10.3382/japr/pfy068}, DOI={10.3382/japr/pfy068}, abstractNote={SUMMARY Disease outbreaks can dramatically impact a producer's production schedule by disrupting the pullet movement into the hen house. One alternative is to early molt laying hens as they are coming into production. Early molted birds had lower production compared to controls with no differences in egg weight or egg components percentages. Bird welfare impacts were minimal as a result of the early molt. This management practice could be employed to allow pullets to be held minimizing production schedule disruptions as a result of a disease outbreak.}, number={2}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Karcher, D.M. and Jones, D.R. and Robison, C.I. and Eberle, K.N. and Gast, R.K. and Anderson, K.E.}, year={2019}, month={Jun}, pages={278–289} }
 @article{eberle_martin_shah_malheiros_livingston_anderson_2018, title={A novel non-invasive method for evaluating electroencephalograms on laying hens}, volume={97}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pex391}, DOI={10.3382/ps/pex391}, abstractNote={Abstract The use of electroencephalograms (EEG) to study the avian brain relative to behavior was conducted as early as the 1960's. EEG readings, combined with visual cues, provide the ability to elucidate and correlate behaviors to neurological and physiological changes in a chicken. The use of EEG recordings in animal models require access to the brain to implant electrodes. Having the ability to observe EEG activity on sensible birds without surgical implantation could broaden the research in this area and give further insight related to the hen's state of awareness. The development, construction, and implementation of a minimally invasive EEG electrode placement method is described. After implementation, test animals were exposed to extreme environmental stressors as part of a concurrent depopulation methods study and EEG placement withstood the condition changes and corresponding animal physical activity. Sixteen white commercial laying hens had three monopolar 32‐gauge needle electrodes inserted subcutaneously and secured to their head and body. Electrodes were attached to a pre‐amplifier which transferred EEG signals to a laptop based recording system. Once the electrodes were in place, the hens were placed in individual treatment/observation chamber then various environmental stressors were applied. Verification that the observed brainwave activity was neural and not muscular was done using a photic stimulation validation test. Behavior observations were recorded to correlate sensible and insensible brainwave activity. The validation test and behavior observations demonstrated the method was successful in measuring EEG in sensible laying hens. The use of a non‐surgical method for recording EEG will broaden research capabilities and enhance the understanding of a hen's response its environment, eliminate the need for invasive surgical procedures, and minimizes the confounding components of anesthesia, brain surgery, and recovery. With further refinements, the method could open new avenues in avian behavioral and physiological research.}, number={3}, journal={Poultry Science}, publisher={Elsevier BV}, author={Eberle, Krista N and Martin, Michael P and Shah, Sanjay and Malheiros, Ramon D and Livingston, Kimberly A and Anderson, Kenneth E}, year={2018}, month={Mar}, pages={860–864} }
 @article{akbari moghaddam kakhki_mousavi_anderson_2018, title={An appraisal of moulting on post-moult egg production and egg weight distribution in white layer hens; meta-analysis}, volume={59}, ISSN={0007-1668 1466-1799}, url={http://dx.doi.org/10.1080/00071668.2018.1432032}, DOI={10.1080/00071668.2018.1432032}, abstractNote={ABSTRACT 1. The aim of this study was to establish how different moulting methods and body weight losses influenced post-moult performance and USDA egg weight distribution. 2. Data on 5 laying flocks (#34–38) of the North Carolina Layer Performance and Management Test were used in this meta-analysis. 3. The moulting methods were non-fasted moulted (NF), short feed restricted (SF), 13-d feed restricted (FR), non-anorexic moult programme (NA), non-anorexic moult programme with low sodium (NALS) as well as non-moulting programme as control treatment. The percentages of targeted body weight loss during the moulting period were 20, 24, 25 and 30% of body weight at the end of the first egg production cycle. 4. Post-moult egg production and egg mass were influenced by all moulting methods. Maximum increase in post-moult egg production rate and egg mass occurred with FR and NF programmes, respectively, at 30% of body weight loss, compared to non-moulted hens. Non-fasting methods reduced mortality rate more effectively than fasting methods. 5. Moulting resulted in increases in percentage of grade A and decreases in percentage of grade B eggs. Non-fasting methods increased percentage of grade A eggs more effectively than fasting methods. Percentage of cracked eggs decreased in moulted rather than non-moulted hens and the lowest rate was associated with the NA programme. 6. Post-moult egg weight was not significantly influenced by moulting methods. However, percentage of body weight reduction affected egg weight. The optimum increment in egg weight was achieved by 24% body weight reduction. 7. Overall, non-fasting methods resulted in similar egg production compared with fasting methods. Considering post-moult mortality and USDA egg weight distribution, non-fasting methods, especially NF and NA programmes, performed much better than fasting methods, indicating that non-fasting moulting methods, which are better for animal welfare, are effective alternatives to fasting methods.}, number={3}, journal={British Poultry Science}, publisher={Informa UK Limited}, author={Akbari Moghaddam Kakhki, R. and Mousavi, Z. and Anderson, K. E.}, year={2018}, month={Feb}, pages={278–285} }
 @article{akbari_bakhshalinejad_anderson_golian_2018, title={Effect of High and Low Stocking Density on Age of Maturity, Egg Production, Egg Size Distribution in White and Brown Layer Hens: A Meta-analysis}, volume={6}, url={http://doi.org/10.22069/psj.2018.14112.1292}, DOI={10.22069/psj.2018.14112.1292}, abstractNote={Data of four layers flocks (#31-34) from North Carolina Layer Performance and Management Test of the Department of Agriculture and Consumer Services were used in the meta-analysis to find if an increase in space allowance can affect egg production traits in white and brown layers. Effects of space allowance of 310 and 413 cm2/bird on layers performance were compared in this study. The increase in space allowance resulted in a significant improvement in egg production, egg mass and daily feed intake in both white and brown layers throughout the first (approximately 490-d; p < 0.001) and second (approximately till 760-d; p < 0.05) cycles of egg production.Space allowance did not affect age of maturity and final body weight at the end of first egg production cycle in both types of layers. Increasing birds space allowance resulted in a reduction in the mortality rate of white layers (p < 0.001) in the first egg production cycle and in the first (p =0.015) and second (p =0.027) egg production cycles in brown layers. The increase in space allowance significantly improved egg weight (p < 0.001) in white layers in the first egg production cycle. A significant increase in egg weight was observed in the first (p =0.014) and second (p =0.050) egg production cycles in brown layers in response to increasing birds space allowance. Egg size distribution was significantly influenced by the space allowance during both egg production cycles in white and brown layers. Space allowance is a management tool that can be used to optimize egg production traits, mortality and egg size distribution in both white and brown layers. Space allowance of 413 cm2/bird could significantly improve egg production and egg size distribution in first and second egg production cycle compared to 310 cm2/bird.}, number={1}, journal={Poultry Science Journal}, publisher={Gorgan University Of Agricultural Sciences & Natural Resources}, author={Akbari, Moghaddam Kakhki R and Bakhshalinejad, R and Anderson, KE and Golian, A}, year={2018}, month={Apr} }
 @article{moghaddam_kakhki_bakhshalinejad_anderson_golian_2018, title={Effect of high and low stocking density on age of maturity, egg production, egg size distribution in white and brown layer hens: a Meta-analysis}, volume={6}, number={1}, journal={Poultry Science Journal}, author={Moghaddam, A. and Kakhki, R. and Bakhshalinejad, R. and Anderson, K. E. and Golian, A.}, year={2018}, pages={71–87} }
 @article{eberle-krish_martin_malheiros_shah_livingston_anderson_2018, title={Evaluation of Ventilation Shutdown in a Multi-level Caged System}, volume={27}, ISSN={1056-6171}, url={http://dx.doi.org/10.3382/japr/pfy036}, DOI={10.3382/japr/pfy036}, abstractNote={SUMMARY In 2015, the United States experienced an extensive outbreak of highly pathogenic avian influenza resulting in the depopulation of 42.1 million commercial egg‐laying hens. Existing mass depopulation methods in multilevel caged systems utilized throughout the egg industry provide a challenge for producers and emergency personnel. An alternative depopulation method with potential for use in the egg industry is ventilation shutdown (VSD), which uses a combination of increasing heat and carbon dioxide (CO2) levels to promote death by hyperthermia and hypoxia. This proof‐of concept study was designed to evaluate the effectiveness of VSD, VSD with supplemental heat (VSDH), and VSD with CO2 (VSDCO2) as alternative mass depopulation methods in a multilevel caged system. Assessment parameters included ambient and core body temperatures, time to death, and survivability. Time to death for VSD, VSDH, and VSDCO2 were 3.75, 2, and 1.5 h, respectively. Survivability in VSD did not meet the flock depopulation standard of 100% lethality. Based on 100% lethality and time to death, VSDH and VSDCO2 are equivalent in their ability to effectively depopulate hens in a multi‐level caged system. Air mixing should be used to prevent stratification of heat or CO2 concentrations between the top and bottom levels of a caged system. While the data emulate a commercial layer environment, application of the techniques in this study still need to be evaluated in a commercial setting.}, number={4}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Eberle-Krish, Krista N. and Martin, Michael P. and Malheiros, Ramon D. and Shah, Sanjay B. and Livingston, Kimberly A. and Anderson, Kenneth E.}, year={2018}, month={Dec}, pages={555–563} }
 @article{jacob_pescatore_anderson_mccrea_shaw_2018, place={Ames, Iowa. Authors}, title={Impact of Free-range Poultry Production Systems on Animal Health, Human Health, Productivity, Environment, Food Safety, and Animal Welfare Issues}, url={https://www.cast-science.org/publication/impact-of-free-range-poultry-production-systems-on-animal-health-human-health-productivity-environment-food-safety-and-animal-welfare-issues/}, number={61}, journal={Issue Paper - Council for Agricultural Science and Technology}, publisher={Council for Agriculture Technology}, author={Jacob, J.P. and Pescatore, A.J. and Anderson, K.E. and McCrea, B. and Shaw, D.P.}, editor={Purswell, J. and Xin, Hongwei and Donoghue, A.Editors}, year={2018} }
 @article{heflin_malheiros_anderson_johnson_raatz_2018, title={Mineral content of eggs differs with hen strain, age, and rearing environment}, volume={97}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pey025}, DOI={10.3382/ps/pey025}, abstractNote={&NA; Egg nutrient quality is strongly influenced by hen diet but is also affected by rearing environment, hen strain, and hen age. The objective of the current study was to determine the effect of: 1) conventional battery cages, 2) enrichable cage systems, 3) enriched colony housing, 4) cage‐free, and 5) free‐range rearing systems on mineral concentrations of whole, dried egg (yolk and albumen combined) from TA Tetra White (TW) and Hy‐Line Brown (HB) hens at 44, 68, and 88 wk of age. We hypothesized that mineral concentration of eggs would differ among rearing systems but not between strains or with hen age. Hens held in enriched colony housing systems produced eggs with 10% lower Mg and 11% lower Mn levels than conventional hens. Concentrations of Ca and Cu were higher (7 and 8%, respectively) in eggs from TW hens than from HB hens. Eggs from HB hens had 8% higher concentrations of Fe, 6% higher Mg and 5% higher Mn than TW hens. Mn was higher in eggs from 44‐wk hens than from 68‐ or 88‐wk hens (16 and 11%, respectively). Interaction effects between rearing environment and hen age were observed for K and Mn concentrations. Eggs from 68‐wk hens in conventional rearing systems contained 14 to 21% more K than eggs from conventional hens at 44‐ and 88 wk and 14 to 18% more than eggs from 68‐wk hens in other rearing systems. At 88 wk of age, hens in conventional rearing systems produced eggs with higher Mn concentration than hens in enrichable or enriched colony housing systems (22 and 23%, respectively). Interactions between rearing environment, hen strain, and hen age were observed for egg Zn levels among 44‐ and 68‐wk hens but were not detectable among 88‐wk hens regardless of rearing system or hen strain. Observed differences in egg mineral content in our study were small and are unlikely to have substantial impact on human nutrition.}, number={5}, journal={Poultry Science}, publisher={Elsevier BV}, author={Heflin, Laura E. and Malheiros, Ramon and Anderson, Kenneth E. and Johnson, LuAnn K. and Raatz, Susan K.}, year={2018}, month={May}, pages={1605–1613} }
 @article{novoa rama_bailey_jones_gast_anderson_brar_taylor_oliver_singh_2018, title={Prevalence, Persistence, and Antimicrobial Resistance of Campylobacter spp. from Eggs and Laying Hens Housed in Five Commercial Housing Systems}, volume={15}, ISSN={1535-3141 1556-7125}, url={http://dx.doi.org/10.1089/fpd.2017.2404}, DOI={10.1089/fpd.2017.2404}, abstractNote={Husbandry practices for laying hens in commercial egg production is a topic of interest from a social, economic, and regulatory standpoint. Animal welfare concerns regarding the use of conventional cages have arisen and consumer perceptions of hen welfare have led to a higher demand for cage-free eggs. The aim of this study was to assess the impact of housing systems on prevalence, persistence, and antimicrobial resistance (AMR) of Campylobacter from laying hens and shell eggs. A total of 425 samples were collected over a 10-month period from the North Carolina Layer Performance and Management Test and Campylobacter isolates were identified by serological, biochemical, and molecular tests. Genetic variability was evaluated using pulsed-field gel electrophoresis (PFGE) and AMR testing was performed. Prevalence of Campylobacter spp. ranged from 11.1% in the enrichable cages to 19.7% in the conventional systems. A greater prevalence of Campylobacter was found in the fecal swab samples from free-range birds compared with those of birds housed in the more intensive housing systems (p > 0.05). Overall, 72 isolates were confirmed as Campylobacter spp. by PCR. More than 90% of the isolates (n = 66) were identified as Campylobacter jejuni, followed by Campylobacter coli (n = 6). C. jejuni isolates displayed high levels of resistance to tetracycline (67%). Genetic variability of Campylobacter was high, with more than 20 PFGE patterns identified. Pattern "a" comprised 42% of isolates from all housing systems and was also the most persistent. This study suggests that housing systems of laying hens used for commercial shell egg production may impact the rate of Campylobacter shedding by layers. Isolation rates and tetracycline resistance levels of this pathogen are still of concern, emphasizing the need for well-implemented biosecurity measures on the farm.}, number={8}, journal={Foodborne Pathogens and Disease}, publisher={Mary Ann Liebert Inc}, author={Novoa Rama, Estefanía and Bailey, Matthew and Jones, Deana R. and Gast, Richard K. and Anderson, Ken and Brar, Jagpinder and Taylor, Rhonda and Oliver, Haley F. and Singh, Manpreet}, year={2018}, month={Aug}, pages={506–516} }
 @article{gradl_curtis_jones_anderson_2017, title={Assessing the impact of egg sweating on Salmonella Enteritidis penetration into shell eggs}, volume={96}, ISSN={["1525-3171"]}, DOI={10.3382/ps/pex011}, abstractNote={&NA; Salmonella Enteritidis (SE) prevalence in eggs is a major concern to the egg industry. Some research has shown that egg sweating can increase Salmonella penetration into egg contents when refrigerated eggs are moved to a warmer temperature. This occurs when eggs are tempered before wash, to minimize thermal cracks. The effect of egg sweating on SE penetration into shell eggs over a 6 week storage period at 4°C was assessed. A 2 × 2 factorial of SE inoculation and egg sweating was utilized. Treatments included (SES) nalidixic acid (NA)‐resistant SE inoculated and sweated, (SENS) NA‐resistant SE inoculated and not sweated, (NSES) buffered peptone water (BPW) inoculated and sweated, and (NSENS) BPW inoculated and not sweated. Eggs were inoculated with 108 SE. Eggs formed condensation for approximately 17 min in a 32°C incubator. Shell rinse, shell emulsion, and egg contents were sampled then enumerated and assessed for prevalence of SE over a 6 wk storage period at 4°C. After wk 1, the SENS shell rinse had higher SE counts (0.32 log10 CFU/mL) than the other 3 treatments, where no SE was enumerated. A significant week by treatment interaction was found for the shell rinse SE detection (P < 0.05). In subsequent weeks, no SE counts were obtained from the egg shell rinse, shell emulsion, or egg contents. The SENS shell rinses had significantly higher SE prevalence than the SES rinses in weeks 1 (100% vs. 34.3%), 2 (57.6% vs. 22.2%), and 3 (38.2% vs. 11.1%) (P < 0.05). In samples from weeks 4, 5, and 6, there was no difference in SE prevalence between SES and SENS. Egg sweating did not increase SE penetration into the shell emulsion across treatment or week (P < 0.05). The decreasing trend of SE prevalence obtained over the study period indicate that refrigeration is effective at inhibiting SE growth. These results indicate that egg sweating occurring under common US egg handling practices is not harmful to egg safety.}, number={7}, journal={POULTRY SCIENCE}, author={Gradl, Janet A. and Curtis, Patricia A. and Jones, Deana R. and Anderson, Kenneth E.}, year={2017}, month={Jul}, pages={2393–2399} }
 @article{mocka_stern_fletcher_anderson_petitte_mozdziak_2017, title={Chemoprevention of spontaneous ovarian cancer in the domestic hen}, volume={96}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pew422}, DOI={10.3382/ps/pew422}, abstractNote={&NA; The hen is an attractive animal model for in vivo testing of agents that thwart ovarian carcinogenesis because ovarian cancer in the domestic hen features clinical and molecular alterations that are similar to ovarian cancer in humans, including a high incidence of p53 mutations. The objective of the study was to test the potential ovarian cancer chemopreventive effect of the p53 stabilizing compound CP‐31398 on hens that spontaneously present the ovarian cancer phenotype. Beginning at 79 wk of age, 576 egg‐laying hens (Gallus domesticus) were randomized to diets containing different amounts of CP‐31398 for 94 wk, 5 d, comprising a control group (C) (n = 144), which was fed a diet containing 0 ppm (mg/kg) of CP‐31398; a low‐dose treatment (LDT) group (n = 144), which was fed a diet containing 100 ppm of CP‐31398; a moderate‐dose treatment (MDT) group (n = 144) which was fed a diet containing 200 ppm of CP‐31398; and a high‐dose treatment (HDT) group (n = 144), which was fed a diet containing 300 ppm of CP‐31398. Hens were killed at 174 wk of age to determine the incidence of ovarian and oviductal adenocarcinomas. Whereas the incidence of localized and metastatic ovarian cancers in the MDT and HDT groups was significantly lower (up to 77%) compared to levels in the C and LDT groups (P < 0.05), the incidence of oviductal cancer was unaffected by CP‐31398. CP‐31398 appears to be an effective tool for chemoprevention against ovarian malignancies, but does not appear to affect oviductal malignancies.}, number={6}, journal={Poultry Science}, publisher={Elsevier BV}, author={Mocka, E.H. and Stern, R.A. and Fletcher, O.J. and Anderson, K.E. and Petitte, J.N. and Mozdziak, P.E.}, year={2017}, month={Jun}, pages={1901–1909} }
 @article{gast_guraya_jones_guard_anderson_karcher_2017, title={Colonization of internal organs by Salmonella serovars Heidelberg and Typhimurium in experimentally infected laying hens housed in enriched colony cages at different stocking densities}, volume={96}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pew375}, DOI={10.3382/ps/pew375}, abstractNote={&NA; Contaminated eggs produced by infected commercial laying flocks are often implicated as sources of human infections with Salmonella Enteritidis, but Salmonella serovars Heidelberg and Typhimurium have also been associated with egg‐transmitted illness. Contamination of the edible contents of eggs is a consequence of the colonization of reproductive tissues in systemically infected hens. In recent years, the animal welfare implications of diverse poultry housing and management systems have been vigorously debated, but the food safety significance of laying hen housing remains uncertain. The present study evaluated the effects of 2 different bird stocking densities on the invasion of internal organs by Salmonella serovars Heidelberg and Typhimurium in groups of experimentally infected laying hens housed in colony cages enriched with perching and nesting areas. Laying hens were distributed at 2 different stocking densities (648 and 973 cm2/bird) into colony cages and (along with a group housed in conventional cages at 648 cm2/bird) orally inoculated with doses of 107 cfu of 2‐strain cocktails of either Salmonella Heidelberg or Salmonella Typhimurium. At 5 to 6 d post‐inoculation, hens were euthanized and samples of internal organs (cecum, liver, spleen, ovary, and oviduct) were removed for bacteriologic culturing. The overall frequency of Salmonella isolation from ceca after inoculation with strains of serovar Heidelberg (83.3%) was significantly (P < 0.001) greater than the corresponding value for strains of serovar Typhimurium (53.8%), whereas Salmonella was recovered significantly more often from both livers (85.2% vs. 53.7%; P < 0.0001) and spleens (78.7% vs. 56.5%; P = 0.0008) after inoculation with strains of serovar Typhimurium than strains of serovar Heidelberg. However, there were no significant differences (P > 0.05) between stocking densities or cage systems in the frequencies of isolation of either Salmonella serovar from any of the five sampled tissues. These results contrast with prior studies, which reported increased susceptibility to internal organ invasion by Salmonella Enteritidis among hens in conventional cages at higher stocking densities.}, number={5}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K. and Guraya, Rupa and Jones, Deana R. and Guard, Jean and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2017}, month={May}, pages={1402–1409} }
 @article{whitaker_worley-davis_brierton_osborne_anderson_livingston_2017, title={Evaluating the Poultry Science Summer Institute (PSSI) as a Recruitment Tool for High School Students from North Carolina Counties to Enter the Prestage Department of Poultry Science}, volume={61}, url={https://www.nactateachers.org/attachments/article/2674/6%20%20Braxton%20Whitaker.pdf}, number={4}, journal={NACTA Journal}, author={Whitaker, Braxton and Worley-Davis, Lynn and Brierton, Sara and Osborne, Jason and Anderson, Kenneth and Livingston, Kimberly}, year={2017}, pages={279–283} }
 @article{gast_guraya_jones_anderson_karcher_2017, title={Frequency and Duration of Fecal Shedding of Salmonella Enteritidis by Experimentally Infected Laying Hens Housed in Enriched Colony Cages at Different Stocking Densities}, volume={4}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2017.00047}, DOI={10.3389/fvets.2017.00047}, abstractNote={Human infections with Salmonella Enteritidis are often attributed to the consumption of contaminated eggs, so the prevalence of this pathogen in egg-laying poultry is an important public health risk factor. Numerous and complex environmental influences on Salmonella persistence and transmission are exerted by management practices and housing facilities used in commercial egg production. In recent years, the animal welfare implications of poultry housing systems have guided the development of alternatives to traditional cage-based housing, but their food safety consequences are not yet fully understood. The present study assessed the effects of different bird stocking densities on the frequency and duration of fecal shedding of S. Enteritidis in groups of experimentally infected laying hens housed in colony cages enriched with perching and nesting areas. In two trials, groups of laying hens were distributed at two stocking densities (648 and 973 cm2/bird) into enriched colony cages and (along with a group housed in conventional cages at 648 cm2/bird) orally inoculated with doses of 1.0 × 108 cfu of S. Enteritidis. At 10 weekly postinoculation intervals, samples of voided feces were collected from beneath each cage and cultured to detect S. Enteritidis. Fecal shedding of S. Enteritidis was detected for up to 10 weeks postinoculation by hens in all three housing treatment groups. The overall frequency of positive fecal cultures was significantly (P < 0.05) greater from conventional cages than from enriched colony cages (at the lower stocking density) for the total of all sampling dates (45.0 vs. 33.3%) and also for samples collected at 4–9 weeks postinfection. Likewise, the frequency of S. Enteritidis isolation from feces from conventional cages was significantly greater than from enriched colony cages (at the higher hen stocking density) for the sum of all samples (45.0 vs. 36.7%) and at 6 weeks postinoculation. Moreover, the frequency of S. Enteritidis fecal recovery from enriched colony cages at the higher hen stocking was significantly greater than from similar cages at the lower stocking density for all 10 sampling dates combined (39.4 vs. 33.3%). These results suggest that stocking density can affect S. Enteritidis intestinal colonization and fecal shedding in laying hens, but some other difference between conventional and enriched colony cage systems appears to exert an additional influence.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Gast, Richard K. and Guraya, Rupa and Jones, Deana R. and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2017}, month={Apr} }
 @article{gast_guraya_jones_guard_anderson_karcher_2017, title={Frequency and Duration of Fecal Shedding of Salmonella Serovars Heidelberg and Typhimurium by Experimentally Infected Laying Hens Housed in Enriched Colony Cages at Different Stocking Densities}, volume={61}, ISSN={["1938-4351"]}, DOI={10.1637/11635-032517-regr}, abstractNote={SUMMARY Eggs contaminated with Salmonella Enteritidis are leading sources of human salmonellosis, but Salmonella Heidelberg and Salmonella Typhimurium are also egg-associated pathogens. The management practices and housing facilities characterizing different systems for housing commercial egg flocks can influence Salmonella persistence and transmission. Animal welfare aspects of poultry housing have been widely debated, but their food safety ramifications are not thoroughly understood. The present study assessed the effects of two different bird stocking densities on the frequency and duration of fecal shedding of strains of Salmonella Heidelberg and Salmonella Typhimurium in groups of experimentally infected laying hens housed in colony cages enriched with perching and nesting areas. In separate trials, laying hens were distributed into two groups housed in enriched colony cages at stocking densities of 648 and 973 cm2/bird, and a third group was housed in conventional cages at 648 cm2/bird. All hens were orally inoculated with doses of 108 colony-forming units (CFU) of either Salmonella Heidelberg or Salmonella Typhimurium. At eight weekly postinoculation intervals, samples of voided feces were collected from beneath each cage and cultured to detect Salmonella. Fecal shedding of Salmonella Heidelberg continued for 8 wk in all housing groups, but Salmonella Typhimurium shedding ceased after as little as 5 wk in enriched colony cages at low stocking density. After Salmonella Heidelberg infection, the overall frequency of positive fecal cultures for all sampling dates combined was significantly (P < 0.05) greater from either conventional cages (51.0%) or enriched colony cages (46.5%) at high stocking density than from enriched colony cages at low stocking density (33.3%). No significant differences in Salmonella Typhimurium fecal isolation were identified between housing groups. These results demonstrate that stocking density can affect intestinal colonization and fecal shedding in laying hens for some (but not necessarily all) Salmonella serovars or strains.}, number={3}, journal={AVIAN DISEASES}, author={Gast, Richard K. and Guraya, Rupa and Jones, Deana R. and Guard, Jean and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2017}, month={Sep}, pages={366–371} }
 @article{lowman_wooten_ashwell_anderson_barne_2017, title={Protein and Caloric Intake on the Reproductive Performance Parameters of Hyline W-36 Parent Stock Males}, volume={16}, ISSN={1682-8356}, url={http://dx.doi.org/10.3923/ijps.2017.242.247}, DOI={10.3923/ijps.2017.242.247}, abstractNote={Background and Objective: Reproduction in poultry has been studied for many years and is a crucial factor to consider when selecting and raising parental lines.Considerable work has focused on broiler breeder males, which has led to the development of feed restriction practices, as well as sex separate rearing, however very little research has been done on layer-type males.In broiler breeders a negative correlation has been found to exist between the Body Weights (BW) and sexual activity of the male.This study was conducted to explore the role of diet during grow out on reproductive traits in leghorn type males.Materials and Methods: Hyline parent stock males were raised on 3 different diets Low (12% CP) Control (18% CP) and High (24% CP).As birds reached sexual maturity, Body Weight (BW), testis size, semen volume, sperm concentration and histology were measured.Results: This trial demonstrated significant (p<0.0001)differences in body weights between the diets.The mean BW of birds were 1214.87,1435.41 and 1475.96g fed on the Low diet, control and high diet, respectively.There were significant differences observed in testicle weights.The Low group had a significantly lower mean weight as compared with Control and High groups.Differences in semen volume were observed between the dietary treatment groups, as well as, differences in sperm concentrations at 18-20 weeks of age.Significant differences in development were seen between High and Low groups upon histological examination and scoring on a 0-6 scale, 0 = Immature (no spermatozoa) to 6 = Fully mature (spermatozoa present in all tubules) of the testes high (3.9)low (1.2).Conclusion: These results suggest that feeding high nutrient dense diets during rearing does not result in a decrease in production as observed in broiler breeder males and that low nutrient diets are not as beneficial in layer males as in broiler breeder males.}, number={7}, journal={International Journal of Poultry Science}, publisher={Science Alert}, author={Lowman, Zachary and Wooten, McCaide and Ashwell, Christopher and Anderson, Kenneth and Barne, H. John}, year={2017}, month={Jun}, pages={242–247} }
 @article{burley_patterson_anderson_2016, title={Alternative feeding strategies and genetics for providing adequate methionine in organic poultry diets with limited use of synthetic amino acids}, volume={72}, ISSN={0043-9339 1743-4777}, url={http://dx.doi.org/10.1017/S0043933915002688}, DOI={10.1017/s0043933915002688}, abstractNote={Currently, synthetic methionine (Met) use in organic poultry diets in the United States is limited to 1, 1, and 1.5 kg per metric tonne of feed for laying hens, broilers, and turkeys and other poultry, respectively. This limitation, and the push to ban the use of synthetic Met entirely, makes it challenging to formulate diets to meet the requirements of these birds. Methionine levels can be maintained in organic poultry diets without synthetics by dramatic increases in dietary crude protein; however, the ramifications of such high crude protein intake are major increases in feed cost and environmental concerns due to increased nitrogen excretion, rises in ammonia emissions, and subsequent welfare issues. This review examines alternative bird genetics and feeding strategies that have the potential to reduce or eliminate the need for synthetic Met in organic poultry diets. Alterative ‘heritage’ breeds may have lower Met needs as a percentage of the total diet; however, these birds have substantially slower growth and are less productive compared to typical commercial breeds. Feeding strategies that have been examined to reduce Met inclusion in the diet, such as allowing birds to forage, providing low Met density diets to encourage increased feed intake and subsequently make up for the Met deficiency, allowing birds to self select between energy-rich ingredients and protein concentrates to meet their Met needs by instinct, or supplementing methyl donors (betaine or choline) or inorganic sulphate, have been shown to make up for marginal Met deficiencies in some instances. However, there is no one solution to this issue that has been found thus far. A combination of genetics, feeding strategies, and alternative ingredients may provide the most favourable solution in the future.}, number={1}, journal={World's Poultry Science Journal}, publisher={Informa UK Limited}, author={Burley, H.K. and Patterson, P.H. and Anderson, K.E.}, year={2016}, month={Mar}, pages={168–177} }
 @article{gast_guraya_jones_anderson_karcher_2016, title={Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens housed in enriched colony cages at different stocking densities}, volume={95}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pew037}, DOI={10.3382/ps/pew037}, abstractNote={Epidemiologic analyses have linked the frequency of human infections with Salmonella enterica subspecies enterica serovar Enteritidis to the consumption of contaminated eggs and thus to the prevalence of this pathogen in commercial egg-laying flocks. Contamination of the edible contents of eggs by Salmonella Enteritidis is a consequence of the colonization of reproductive tissues in systemically infected hens. The animal welfare implications of laying hen housing systems have been widely debated, but no definitive consensus has yet emerged about the food safety significance of poultry housing options. The present study sought to determine the effects of two different bird stocking densities on the invasion of internal organs by Salmonella Enteritidis in groups of experimentally infected laying hens housed in colony cages enriched with perching and nesting areas. In two trials, groups of laying hens were distributed at two different stocking densities into colony cages and (along with a group housed in conventional cages) orally inoculated with doses of 1.0 × 10(7) cfu of Salmonella Enteritidis. At 5 to 6 d post-inoculation, hens were euthanized and samples of internal organs were removed for bacteriologic culturing. For both trials combined, Salmonella Enteritidis was recovered at a significantly (P < 0.05) greater frequency from hens in enriched colony cages at the higher stocking density than at the lower density from livers (75.0% vs. 51.4%) and ovaries (51.4% vs. 30.6%). However, spleens from hens in enriched colony cages at the higher stocking density were significantly less often positive for Salmonella Enteritidis than from hens in conventional cages at that same density (90.3% vs. 68.1%). These results suggest that stocking density can influence the susceptibility of hens to Salmonella Enteritidis, but other housing systems parameters may also contribute to the outcome of infections.}, number={6}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K. and Guraya, Rupa and Jones, Deana R. and Anderson, Kenneth E. and Karcher, Darrin M.}, year={2016}, month={Jun}, pages={1363–1369} }
 @article{regmi_nelson_steibel_anderson_karcher_2016, title={Comparisons of bone properties and keel deformities between strains and housing systems in end-of-lay hens}, volume={95}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pew199}, DOI={10.3382/ps/pew199}, abstractNote={Susceptibility of caged layers to osteoporosis and cage layer fatigue has generated interest in newer housing systems that favor increased load-bearing activities. However, high incidences of fractures incurred during lay period have been reported in these newer systems. This study is aimed at determining the housing and strain effects on bone properties: dry weight, percentage ash content, cortical density (CBD), cortical thickness (CBT), and keel bone deformities. Tibia, femur, and keel from Hy-Line Brown (HB), Hy-Line Silver Brown (SB), and Barred Plymouth Rock (BR) hens housed in conventional cages (CC), cage-free (CF), and cage-free with range (outdoor access; R) were studied. At 78 wk, 60 hens from each strain and housing system combination were euthanized and bones were excised for analysis. Quantitative computed tomography (QCT) was used to measure CBD and CBT in each bone. Three-dimensional images of keels were generated from software using QCT scans to analyze the deformities. Tibiae CBT was greater (P < 0.01) in BR compared to other two strains. Between housing systems, CBT was greater (P < 0.05) for mid and distal tibia of R and CF compared to CC. Tibiae and femoral cortex were denser (P < 0.05) in BR compared to HB and SB. There was no effect of housing system for femur CBD, but CBD was greater (P < 0.05) for middle and distal tibia of birds housed in R compared to CC. CBD for keel bone was greater (P < 0.05) in CF and R birds compared to CC birds. The housing system did not influence the dry bone weight and ash percentage of tibiae and femur. Each housing system was associated with high prevalence (>90%) of keel deformities and the housing and genotype influenced the type of deformity. These findings indicate that range and cage-free housing may have beneficial impact on tibia and keel bone integrity compared to conventional cages but the improvement may not be sufficient to prevent fractures or deformities of keel.}, number={10}, journal={Poultry Science}, publisher={Elsevier BV}, author={Regmi, P. and Nelson, N. and Steibel, J.P. and Anderson, K.E. and Karcher, D.M.}, year={2016}, month={Oct}, pages={2225–2234} }
 @article{burley_anderson_patterson_tillman_2016, title={Formulation challenges of organic poultry diets with readily available ingredients and limited synthetic methionine}, volume={25}, ISSN={1056-6171}, url={http://dx.doi.org/10.3382/japr/pfw012}, DOI={10.3382/japr/pfw012}, abstractNote={Abstract Organic agriculture has increased greatly over the past several years as consumer demand for these products has risen. Organic meat production, including poultry, has grown especially quickly, resulting in increasingly stringent guidelines being put in place to ensure safe, uniform, and ideal products for these consumers. Feed formulation and manufacturing for organic poultry in the United States are strictly regulated by the United States Department of Agriculture National Organic Program. Currently, no synthetic amino acids are allowed to be used in organic poultry diets in the United States except for limited quantities of synthetic methionine since it is typically considered the first or second limiting amino acid in corn and soybean meal based poultry diets and it is a critical nutrient for maintaining bird growth and productive performance, especially regarding egg size in laying hens. The aim of the review herein is to discuss the impacts that current organic regulations on synthetic methionine have on diet formulation when using readily available ingredients. High levels of crude protein must be used to meet bird methionine requirements with this restriction in place, which both increases feed costs and can have negative impacts on bird health and on air quality and the surrounding environment due to increased ammonia emissions. Atypical feed formulation strategies have been explored to address this issue, including such methods as feeding alternative ingredients and providing forage materials. Another possibility would be to use an average lifetime maximum inclusion rate for synthetic methionine, which may allow for better flexibility to provide sufficient methionine throughout various phases of growth and production since the requirements of the bird change with age.}, number={3}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Burley, H.K. and Anderson, K.E. and Patterson, P.H. and Tillman, P.B.}, year={2016}, month={Sep}, pages={443–454} }
 @article{burley_patterson_anderson_2015, title={Alternative ingredients for providing adequate methionine in organic poultry diets in the United States with limited synthetic amino acid use}, volume={71}, ISSN={0043-9339 1743-4777}, url={http://dx.doi.org/10.1017/S0043933915002196}, DOI={10.1017/s0043933915002196}, abstractNote={Synthetic methionine use is currently limited to 1 kg and 1.5 kg per metric tonne (2, 2, and 3 lbs per short ton) of feed for organic laying hens, broilers, and turkeys and other poultry, respectively, in the United States of America. All other synthetic amino acids (AA) have been banned from use in organic poultry diets in this country. It is challenging to provide sufficient methionine (Met) to maintain bird growth and productive performance up to current industry standards given the recent restrictions that have been placed on synthetic Met. Without synthetic AA, Met requirements can alternatively be obtained for organic poultry by dramatically increasing dietary crude protein (CP) e.g. via additional inclusion of expeller-pressed soybean meal to the diets. However, this strategy leads to both major increases in feed costs and environmental concerns due to increasing nitrogen excretion, with concurrent rises in ammonia emissions, and corresponding welfare issues due to ammonia and litter quality. This review aims to examine feed ingredients that may contribute to a solution to this issue. Otherwise, further negative impacts may soon be felt from the current limitation on synthetic Met or a potential ban on its entire use in the future.}, number={3}, journal={World's Poultry Science Journal}, publisher={Informa UK Limited}, author={Burley, H.K. and Patterson, P.H. and Anderson, K.E.}, year={2015}, month={Sep}, pages={493–504} }
 @article{gast_guraya_jones_anderson_2015, title={Persistence of fecal shedding of Salmonella Enteritidis by experimentally infected laying hens housed in conventional or enriched cages}, volume={94}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pev113}, DOI={10.3382/ps/pev113}, abstractNote={Salmonella Enteritidis can be deposited inside eggs laid by infected hens, so the prevalence of this pathogen in commercial egg-producing flocks is an important risk factor for human illness. Opportunities for the introduction, transmission, and persistence of salmonellae in poultry are potentially influenced by flock housing and management systems. Animal welfare concerns have spurred the development of alternatives to traditional cage-based housing. However, the consequences of poultry housing systems for food safety have not been fully resolved by prior research. The present study assessed the effects of two different housing systems (conventional cages and colony cages enriched with perching and nesting areas) on the persistence of fecal shedding of Salmonella Enteritidis by groups of experimentally infected laying hens. In each of two trials, 136 hens were distributed among cages of both housing systems and orally inoculated with doses of 10(8) cfu of Salmonella Enteritidis (phage type 13a in one trial and phage type 4 in the other). At weekly intervals, samples of voided feces were collected from beneath each cage and cultured to detect Salmonella Enteritidis. Fecal shedding of Salmonella Enteritidis was detected for up to 8 wk post-inoculation by hens housed in enriched colony cages and 10 wk by hens housed in conventional cages. For both trials combined, the frequency of positive fecal cultures was significantly (P < 0.05) greater for conventional cages than for enriched colony cages at 1 wk (84.7 vs. 71.5%), 2 wk (54.2 vs. 31.3%), 3 wk (21.5 vs. 7.6%), and 4 wk (9.7 vs. 2.8%) post-inoculation. These results demonstrate that the susceptibility of hens to intestinal colonization by Salmonella Enteritidis can differ between conventional and enriched cage-based production systems, although this effect does not necessarily translate into a corresponding difference in the longer-term persistence of fecal shedding.}, number={7}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K. and Guraya, Rupa and Jones, Deana R. and Anderson, Kenneth E.}, year={2015}, month={Jul}, pages={1650–1656} }
 @article{gast_guraya_jones_anderson_2014, title={Contamination of eggs by Salmonella Enteritidis in experimentally infected laying hens housed in conventional or enriched cages}, volume={93}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.2013-03641}, DOI={10.3382/ps.2013-03641}, abstractNote={Both epidemiologic analyses and active disease surveillance confirm an ongoing strong association between human salmonellosis and the prevalence of Salmonella enterica subspecies enterica serovar Enteritidis in commercial egg flocks. The majority of human illnesses caused by this pathogen are attributed to the consumption of contaminated eggs. Animal welfare concerns have increasingly influenced commercial poultry production practices in recent years, but the food safety implications of different housing systems for egg-laying hens are not definitively understood. The present study assessed the effects of 2 different housing systems (conventional cages and colony cages enriched with perching and nesting areas) on the frequency of Salmonella Enteritidis contamination inside eggs laid by experimentally infected laying hens. In each of 2 trials, groups of laying hens housed in each cage system were orally inoculated with doses of 1.0 × 10(8) cfu of Salmonella Enteritidis. All eggs laid between 5 and 25 d postinoculation were collected and cultured to detect internal contamination with Salmonella Enteritidis. For both trials combined, Salmonella Enteritidis was recovered from 3.97% of eggs laid by hens in conventional cages and 3.58% of eggs laid by hens in enriched cages. No significant differences (P > 0.05) in the frequency of egg contamination were observed between the 2 housing systems.}, number={3}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K. and Guraya, Rupa and Jones, Deana R. and Anderson, Kenneth E.}, year={2014}, month={Mar}, pages={728–733} }
 @article{vukina_anderson_muth_2014, title={Economic effects of proposed changes in living conditions for laying hens under the National Organic Program}, volume={23}, ISSN={["1537-0437"]}, DOI={10.3382/japr.2013-00834}, abstractNote={Abstract In this paper, we estimate the costs and benefits of implementing the proposed National Organic Program for laying hens compared with alternatives. For the regulatory proposals under option 2, the regulatory cost will be zero because most producers are already in compliance with the proposed regulation. The anticipated benefits of this regulation will be zero as well, because the current market prices already reflect consumers’ willingness to pay for the existing animal welfare conditions. For the regulatory proposals under option 3, before market adjustments, the average regulatory burden for the entire organic egg industry will amount to $0.09 per dozen eggs, with extreme variations between $0 for small operations and $2.30 per dozen for large operations. If we rely on the average price of organic eggs, $2.69 per dozen, and assume a maximum estimated benefit associated with improved animal welfare conditions, that consumers would be willing to pay of about 30% above the current market price, the estimated benefit of regulation amounts to $0.81 per dozen eggs. Based on the findings, we conclude that option 2 is welfare neutral and could be easily adopted because it already has been adopted by representative producers. For option 3, the benefit-cost ratio is larger than 1, which indicates that the proposal passes the benefit-cost ratio test. The obtained result, however, has to be interpreted with serious reservation because of the differential effect that the proposed regulation would have on different industry participants. Under option 3, the effect of the proposed changes on small organic egg producers is negligible because most small producers are operating under conditions similar to the proposed living standards. However, costs will increase substantially for large organic egg producers and likely cause a substantial number of producers to exit organic production and switch to conventional production, which would cause a substantial decline in the prices of conventional eggs and organic feed in the short run.}, number={1}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Vukina, Tomislav and Anderson, Kenneth and Muth, Mary K.}, year={2014}, month={Mar}, pages={80–93} }
 @article{harris_fletcher_anderson_petitte_kopelovich_mozdziak_2014, title={Epithelial Cell Tumors of the Hen Reproductive Tract}, volume={58}, ISSN={["1938-4351"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84896380321&partnerID=MN8TOARS}, DOI={10.1637/10643-082313-Reg.1}, abstractNote={SUMMARY There is a paucity of preclinical models that simulate the development of ovarian tumors in humans. At present, the egg-laying hen appears to be the most promising model to study the spontaneous occurrence of ovarian tumors in the clinical setting. Although gross classification and histologic grade of tumors have been used prognostically in women with ovarian tumors, there is currently no single system that is universally used to classify reproductive tumors in the hen. Four hundred and one 192-wk-old egg-laying hens were necropsied to determine the incidence of reproductive tumors using both gross pathology and histologic classification. Gross pathologic classifications were designated as follows: birds presenting with ovarian tumors only (class 1), those presenting with oviductal and ovarian tumors (class 2), those with ovarian and oviductal tumors that metastasized to the gastrointestinal tract (class 3), those with ovarian and oviductal tumors that metastasized to the gastrointestinal tract and other distant organs (class 4), those with oviductal tumors only (class 5), those with oviductal tumors that metastasized to other organs with no ovarian involvement (class 6), and those with ovarian tumors that metastasized to other organs with no oviductal involvement (class 7), including birds with gastrointestinal tumors and no reproductive involvement (GI only) and those with no tumors (normal). Histopathologic classifications range from grades 1 to 3 and are based on mitotic developments and cellular differentiation. An updated gross pathology and histologic classification systems for the hen reproductive malignancies provides a method to report the range of reproductive tumors revealed in a flock of aged laying hens. RESUMEN Tumores de células epiteliales del tracto reproductivo de la gallina. Hay una escasez de modelos preclínicos que simulen el desarrollo de los tumores de ovario en humanos. En la actualidad, la gallina de postura parece ser el modelo más prometedor para estudiar la aparición espontánea de tumores en el ovario en el ámbito clínico. Aunque la clasificación macroscópica y el grado histológico de los tumores se han utilizado para realizar el pronóstico en mujeres con tumores de ovario, no existe actualmente ningún sistema que se utilice universalmente para clasificar tumores reproductivos en la gallina. Se realizó la necropsia de 401 gallinas de postura de 192 semanas de edad para determinar la incidencia de los tumores del aparato reproductor utilizando tanto patología macroscópica y clasificación histológica. Las clasificaciones patológicas macroscópicas fueron designadas de la siguiente manera: las aves que presentaron únicamente tumores de ovario (clase 1), los que presentan tumores de ovario y oviducto (clase 2), aquellos con tumores de ovario y oviducto y con metástasis en el tracto gastrointestinal (clase 3), las aves que tienen tumores de ovario y oviducto, con metástasis en el tracto gastrointestinal y otros órganos distantes (clase 4), las aves que tienen tumores del oviducto solamente (clase 5), aquellas con tumores del oviducto con metástasis a otros órganos sin la participación de ovario (clase 6), y las aves que tienen tumores de ovario con metástasis a otros órganos sin la participación del oviducto (clase 7), incluidas las aves con tumores gastrointestinales y sin compromiso del aparato reproductivo (sólo tracto gastrointestinal) y las aves que no tienen tumores (normales). Las clasificaciones histopatológicas tuvieron un rango que va desde los grados 1 a 3, y se basaron en el desarrollo de mitosis y diferenciación celular. Una descripción patológica macroscópica actualizada y los sistemas de clasificación histológica de los tumores malignos reproductivos de la gallina proporcionan un método para reportar la gama de tumores reproductivos detectados en una parvada de gallinas ponedoras de edad.}, number={1}, journal={Avian Diseases}, author={Harris, E.A. and Fletcher, O.J. and Anderson, K.E. and Petitte, J.N. and Kopelovich, L. and Mozdziak, P.E.}, year={2014}, month={Mar}, pages={95–101} }
 @article{gast_guraya_jones_anderson_2014, title={Horizontal transmission of Salmonella Enteritidis in experimentally infected laying hens housed in conventional or enriched cages}, volume={93}, ISSN={["1525-3171"]}, DOI={10.3382/ps.2014-04237}, abstractNote={The majority of human illnesses caused by Salmonella Enteritidis are attributed to contaminated eggs, and the prevalence of this pathogen in commercial laying flocks has been identified as a leading epidemiologic risk factor. Flock housing and management systems can affect opportunities for the introduction, transmission, and persistence of foodborne pathogens in poultry. The animal welfare implications of different types of housing for laying hens have been widely discussed in recent years, but the food safety consequences of these production systems remain incompletely understood. The present study assessed the effects of 2 different housing systems (conventional cages and colony cages enriched with perching and nesting areas) on the horizontal transmission of experimentally introduced Salmonella Enteritidis infection within groups of laying hens. In each of 2 trials, 136 hens were distributed among cages of both housing systems and approximately one-third of the hens in each cage were orally inoculated with doses of 10(8) cfu of Salmonella Enteritidis (phage type 13a in one trial and phage type 4 in the other). At regular intervals through 23 d postinoculation, cloacal swabs were collected from all hens (inoculated and uninoculated) and cultured for Salmonella Enteritidis. Horizontal contact transmission of infection was observed for both Salmonella Enteritidis strains, reaching peak prevalence values of 27.1% of uninoculated hens in conventional cages and 22.7% in enriched cages. However, no significant differences (P > 0.05) in the overall frequencies of horizontal Salmonella Enteritidis transmission were evident between the 2 types of housing. These results suggest that opportunities for Salmonella Enteritidis infection to spread horizontally throughout laying flocks may be similar in conventional and enriched cage-based production systems.}, number={12}, journal={POULTRY SCIENCE}, author={Gast, Richard K. and Guraya, Rupa and Jones, Deana R. and Anderson, Kenneth E.}, year={2014}, month={Dec}, pages={3145–3151} }
 @article{vukina_anderson_muth_2014, title={Proposed changes in living conditions for broilers under the National Organic Program will have limited economic effects}, volume={23}, ISSN={1056-6171}, url={http://dx.doi.org/10.3382/japr.2013-00896}, DOI={10.3382/japr.2013-00896}, abstractNote={Abstract In the current paper, we estimate the costs and benefits of implementing the proposed rule for changes in living conditions for organic broilers. In contrast to the effects of the proposed rule for changes in living conditions for laying hens, the effects of the rule on organic broilers is anticipated to be relatively limited. All producers are already in compliance with option 2 of the rule, and changes required under option 3 are minimal for most producers. Using the per-farm estimated regulatory costs and the estimates of production volumes and actual prices, the total estimated annual industry cost under option 3 is $2.4 million, which represents 0.1% of total industry revenue. The estimated benefits associated with this type of perceived animal welfare improvement are high enough to cover the anticipated cost, and the proposed option easily passes the benefit-to-cost ratio test.}, number={2}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Vukina, Tomislav and Anderson, Kenneth and Muth, Mary K.}, year={2014}, month={Jun}, pages={233–243} }
 @inbook{curtis_anderson_2014, place={Auburn, AL}, title={Specialty Eggs}, url={https://aufsi.catalog.instructure.com/courses/specialtyeggs}, booktitle={The Virtual Food Systems Training Consortium (VFSTC)}, publisher={Auburn University}, author={Curtis, P.A. and Anderson, K.E.}, year={2014} }
 @article{anderson_2014, title={Time study examining the effect of range, cage-free, and cage environments on man-hours committed to bird care in 3 brown egg layer strains}, volume={23}, ISSN={["1537-0437"]}, DOI={10.3382/japr.2013-00852}, abstractNote={Abstract Growing consumer awareness concerning layer hen welfare has caused the egg industry to consider alternative environments for egg-laying hens. However, the time commitment for alternative care has not been researched in detail since the 1950s. In 2 experiments, we evaluated the man-hour commitment associated with 3 different environments, including range (R), cage-free (CF), and cage systems (C). Concurrently within the R and CF systems, 3 strains of birds, Hy-Line Silver Brown, Hy-Line Brown, and Barred Plymouth Rock, were examined to see if strain differences were associated with man-hours associated for care. All birds were raised within the environment they were going to be laying in at 17 wk of age, the time data collection started. The system study was a 3-factor randomized design that commenced at 17 wk, when the laying phase commenced with 8 R replicates, 24 CF replicates, and 4 C replicates. The strain study consisted of R and CF systems and 3 strains of Hy-Line Brown, Hy-Line Silver Brown, and Barred Plymouth Rock. All husbandry was provided as appropriate to the production system and in accordance with the approved animal care procedures. Time was recorded for all of the procedures done within the replicates (i.e., egg collection, feeding, and so on). The data were transformed first by man-hours per bird housed and second by man-hours per bird surviving. All time data were analyzed using PROC GLM in SAS. Man-hours per hen decreased from 17 to 37 wk in all production systems. The production environment C required only 0.334 h/hen housed, which is lower as compared with either the CF at 0.486 h/hen housed or R at 1.268 h/hen housed. Strain alone did not influence man-hours; however, the strain with the poorest livability had the greatest man-hour requirement for hens surviving. This study substantiates previous findings that moving from intensive to extensive production systems will increase man-hours per hen by 3 or 4 times.}, number={1}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Anderson, Kenneth E.}, year={2014}, month={Mar}, pages={108–115} }
 @article{herman_huffman_anderson_golden_2014, title={“A.S.P.I.R.E.” ACT Supplemental Preparation In Rural Education: An Initiative Designed to Bridge Deficits on the ACT College Entrance Examination}, volume={58}, url={https://www.nactateachers.org/attachments/article/2219/17.%20Herman_NACTA%20Journal.pdf}, number={3}, journal={NACTA}, author={Herman, M.V. and Huffman, R.E. and Anderson, K.E. and Golden, J.B.}, year={2014}, pages={269–271} }
 @inbook{anderson_2013, title={Animal Welfare Regulations and Food Production}, ISBN={9781118227763 9781118227787}, url={http://dx.doi.org/10.1002/9781118227763.ch11}, DOI={10.1002/9781118227763.ch11}, abstractNote={Animal well-being is not a new issue and concerns are continuing to expand and gain favor in the developed countries where approximately 98% of the population is fed by 2%. The animal welfare regulations that impact food production are relatively recent in their development, global in nature and influence the free trade of food products of animal origin and ultimately their cost to the end consumer. The people involved in the animal welfare issue are many and diverse. American farmers and ranchers are viewed by 90% of the public as an essential part of the American life and 88% of the public thinks they do a good job of producing healthy food at a reasonable price. Each of the animal production companies need to work to get their company to develop and adopt animal care standards.}, booktitle={Guide to US Food Laws and Regulations}, publisher={John Wiley & Sons, Ltd}, author={Anderson, Kenneth E.}, year={2013}, month={Jul}, pages={227–238} }
 @article{anderson_havenstein_jenkins_osborne_2013, title={Changes in commercial laying stock performance, 1958–2011: thirty-seven flocks of the North Carolina random sample and subsequent layer performance and management tests}, volume={69}, ISSN={0043-9339 1743-4777}, url={http://dx.doi.org/10.1017/S0043933913000536}, DOI={10.1017/s0043933913000536}, abstractNote={Thirty-seven layer performance tests have been conducted at North Carolina State University during the past 53 years. Originally established as the North Carolina Random Sample Layer Test (NCRSLT), all of the test flocks have been hatched and housed at the Poultry Unit of the North Carolina Department of Agriculture and Consumer Service's Piedmont Research Station at Salisbury, North Carolina. In 1988, the NCRSLT name was changed to the North Carolina Layer Performance and Management Test (NCLP&MT) reflecting changes in the testing procedures to include the evaluation of management practices used by commercial egg producers. Strain testing and evaluating the relative egg production of commercially available egg production stocks began in 1911, and the number of such Random Sample Tests in North America peaked at 23 in approximately 1968. The mission for the NCRSLT to provide an unbiased evaluation of the overall performance of strains, evolved to include the effects of various housing and husbandry practices on the performance of the genetic stocks entered into the test. Test results have been distributed to the industry throughout the USA as well as to producers in 22 other countries throughout the world. In addition, the internet site for the NCLP&MT http://poultry.ces.ncsu.edu/layer-performance/ allows the distribution of the results to many other interested university and government officials. This review of the first 37 North Carolina layer tests shows continuing improvements in egg production, reduction in body weight and feed consumption, increases in egg weight and feed conversion, improvements in liveability, and an improvement in egg quality from the commercially available white and brown egg strains. These changes have continued throughout the 50+ year history of the tests, and the changes observed have been brought about primarily by poultry breeding companies applying quantitative genetics for the improvement of the layer stocks used worldwide.}, number={3}, journal={World's Poultry Science Journal}, publisher={Informa UK Limited}, author={Anderson, K.E. and Havenstein, G.B. and Jenkins, P.K. and Osborne, J.}, year={2013}, month={Sep}, pages={489–514} }
 @article{herman_huffman_anderson_golden_2013, title={College entrance examination score deficits in Ag-intensive, Rural, Socioeconomically Distressed North Carolina Counties: An inherent risk to the Post-secondary degree attainment for rural high school students}, volume={57}, url={https://www.nactateachers.org/attachments/article/2145/11%20Herman%20Dec2013.pdf}, number={4}, journal={NACTA}, author={Herman, M.V. and Huffman, R.E. and Anderson, K.E. and Golden, J.B.}, year={2013}, pages={45–50} }
 @article{gast_guraya_jones_anderson_2013, title={Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens housed in conventional or enriched cages}, volume={92}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.2012-02811}, DOI={10.3382/ps.2012-02811}, abstractNote={More human illnesses caused by Salmonella enterica subspecies enterica serovar Enteritidis throughout the world have been linked to the consumption of contaminated eggs than to any other food vehicle. Deposition of this pathogen in the edible contents of eggs occurs when systemic infections of laying hens involve colonization of reproductive organs. In recent years, the consequences of different housing systems for laying flocks have become the focus of international attention from both animal welfare and public health perspectives. Nevertheless, many questions remain unresolved regarding the food safety implications of various laying hen production systems. The present study assessed the effects of 2 different housing types (conventional cages and colony cages enriched with perching, nesting, and scratching areas) on the invasion of internal organs by Salmonella Enteritidis in experimentally infected laying hens. In 2 trials, groups of laying hens housed in each cage system were orally inoculated with doses of 1.0 × 10(7) cfu of Salmonella Enteritidis. At 5 to 6 d postinoculation, hens were euthanized and samples of internal organs were removed for bacteriologic culturing. For both trials combined, Salmonella Enteritidis was recovered from 95.3% of cecal samples, with no significant differences observed between housing systems. However, Salmonella Enteritidis was detected at significantly (P < 0.05) higher frequencies from hens in conventional cages than from hens in enriched cages for samples of livers (96.9 vs. 75.0%), spleens (93.8 vs. 53.1%), ovaries (25.0 vs. 10.4%), and oviducts (19.8 vs. 2.1%). These results demonstrate that differences in housing systems for egg-laying flocks can affect the susceptibility of hens to colonization of internal organs by Salmonella Enteritidis.}, number={2}, journal={Poultry Science}, publisher={Elsevier BV}, author={Gast, Richard K. and Guraya, Rupa and Jones, Deana R. and Anderson, Kenneth E.}, year={2013}, month={Feb}, pages={468–473} }
 @article{anderson_2013, title={Comparison of fatty acid, cholesterol, vitamin A and E composition, and trans fats in eggs from brown and white egg strains that were molted or nonmolted}, volume={92}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.2013-03377}, DOI={10.3382/ps.2013-03377}, abstractNote={The impact of egg color, hen strain, and molting on the nutritional composition of eggs is limited. Therefore, this study compared nutritional composition and component percentages of cage-produced shell eggs with respect to egg color, hen strain, and molt. Four strains were selected from the North Carolina Layer Performance and Management Test: Hy-Line Brown (HB) and Bovans Brown (BB), and Hy-Line W-36 (HW) and Bovans White (BovW) were selected. Two groups from each strain were selected and 2 groups of molted HW and BovW were selected and compared with their nonmolted counterparts to examine the molt's impact. Two sets of eggs from each replicate were collected simultaneously at 101 wk of age. One sample of eggs was broken into a 12-egg pool stomached for 3 min (n = 12 samples), then divided into six 50-mL tubes, sealed, and frozen to be sent for cholesterol, n-3 fatty acids, saturated fat, monounsaturated fats, polyunsaturated fats, β-carotene, vitamin A, and vitamin E analyses. The other set of 12 eggs was then assessed for component percentages. The HW eggs had a greater (P < 0.05) percentage of yolk than the BovW eggs of 28.12 versus 27.00%, respectively; however, the BovW eggs had 1.0% more albumen. The HB and BB egg components were not different. Brown eggs were heavier (P < 0.01) than white eggs. White eggs had greater (P < 0.0001) percent yolk and the brown eggs had greater (P < 0.0001) percent albumen. The eggs from molted hens had a greater (P < 0.001) percent shell. Total fat content in the samples was (P < 0.05) higher in white eggs by 0.70% than brown eggs due to increased saturated and polyunsaturated fats. The molting of hens reduced (P < 0.01) saturated fats by 0.21% in the egg. Vitamin A levels were higher (P < 0.0001) in white eggs, and vitamin E was higher (P < 0.0001) in brown eggs. Strain and molt appear to influence nutrient composition and component percentages in eggs produced from laying hens.}, number={12}, journal={Poultry Science}, publisher={Elsevier BV}, author={Anderson, Kenneth E.}, year={2013}, month={Dec}, pages={3259–3265} }
 @article{anderson_klein_golden_2013, title={Effect of Alternative Production and Management Environments on Layer Reproduction System Development}, volume={12}, ISSN={1682-8356}, url={http://dx.doi.org/10.3923/ijps.2013.251.253}, DOI={10.3923/ijps.2013.251.253}, abstractNote={Three different production environments were evaluated for their impact on laying hen reproduction by assessing the ovary and oviducts for the presence of physiological variations. The three environments included free-range (FR = 60), cage-free (CF = 55) and battery cage (BC = 50). The ovaries and oviducts from these hens were collected and weighed during necropsy, then stored in a freezer at -20°F for later analysis. The analysis included the oviduct length and the number of Post-Ovulatory Follicles (POFs), atretic follicles, hierarchical follicles (H = 12-40 mm), small yellow follicles (SY = 5-12 mm), large white follicles (LW = 2-5 mm), small white follicles (SW = <2 mm) and tumor numbers if present on each ovary. Free-range hens had significantly heavier oviduct weights, at 19.4 and 13.5% heavier than oviducts of battery cage and cage-free hens, respectively. The free-range hens also exhibited an increased presence of tumors as well as a n increased frequency of multiple tumors on the oviducts. Hens housed in the free-range and battery cage environments had increased numbers of LW follicles compared to the cage-free hens. In addition, the free- range hens had a significantly smaller number of SW follicles when compared to the battery cage hens. Contrary to the popular belief that birds raised in free-range or cage-free environments provide healthier production alternatives than conventional battery cages, this study does not suggest that there is a significant physiological impact on the reproductive capacity of hens housed in these different production environments. However, oviduct health appears to be better in the battery cage and cage-free environments.}, number={4}, journal={International Journal of Poultry Science}, publisher={Science Alert}, author={Anderson, K.E. and Klein, A.N. and Golden, J.B.}, year={2013}, month={Apr}, pages={251–253} }
 @article{rodriguez_barnes_anderson_whitaker_berchuck_petitte_lancaster_wenham_turbov_day_et al._2013, title={Evidence of a Chemopreventive Effect of Progestin Unrelated to Ovulation on Reproductive Tract Cancers in the Egg-laying Hen}, volume={6}, ISSN={1940-6207 1940-6215}, url={http://dx.doi.org/10.1158/1940-6207.CAPR-12-0426}, DOI={10.1158/1940-6207.capr-12-0426}, abstractNote={Epidemiologic, laboratory, and animal evidence suggests that progestins and vitamin D may be potent ovarian cancer preventives. Our objectives were to evaluate progestins as reproductive tract cancer chemopreventives in the chicken, determine whether restricted ovulation affected the incidence of reproductive tract tumors, and assess whether vitamin D would confer cancer protection either alone or in addition to progestin. A total of 2,400 two-year-old Single Comb White Leghorns were randomized into six groups (400 each) with hormonal and dietary manipulation for 2 years as follows: (i) no intervention, regular feed/caloric intake, (ii) control, (iii) vitamin D, (iv) the progestin levonorgestrel, (v) vitamin D plus levonorgestrel, and (vi) the progestin Provera (medroxyprogesterone acetate). Groups 2 to 6 were caloric restricted to inhibit ovulation. Our results indicated that caloric restriction decreased egg production by more than 60%, and was associated with a greater than 70% decrease in reproductive tract cancers. Ovulatory events did not differ among the caloric-restricted groups (groups 2–6), except for the group receiving levonorgestrel, which had fewer ovulatory events than controls (P = 0.046). After correcting for egg production, birds receiving progestins had significantly fewer reproductive tract cancers [OR, 0.61; confidence interval (CI), 0.39–0.95; P = 0.03], with similar proportionate reductions in tumors arising in either the ovary or oviduct. Vitamin D did not significantly affect cancer incidence overall, or add to the cancer preventive effect of progestins. This study suggests a protective effect of progestins against ovarian and oviductal cancers. These data support the concept that progestins provide a chemopreventive effect unrelated to ovulation. Cancer Prev Res; 6(12); 1283–92. ©2013 AACR.}, number={12}, journal={Cancer Prevention Research}, publisher={American Association for Cancer Research (AACR)}, author={Rodriguez, G. C. and Barnes, H. J. and Anderson, K. E. and Whitaker, R. S. and Berchuck, A. and Petitte, J. N. and Lancaster, J. M. and Wenham, R. M. and Turbov, J. M. and Day, R. and et al.}, year={2013}, month={Oct}, pages={1283–1292} }
 @article{jones_anderson_2013, title={Housing system and laying hen strain impacts on egg microbiology}, volume={92}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.2012-02799}, DOI={10.3382/ps.2012-02799}, abstractNote={Alternative hen housing is becoming more commonplace in the egg market. However, a complete understanding of the implications for alternative housing systems on egg safety has not been achieved. The current study examines the impact of housing Hy-Line Brown, Hy-Line Silver Brown, and Barred Plymouth Rock hens in conventional cage, cage-free, and free range egg production systems on shell microbiology. Eggs were collected at 4 sampling periods. Egg shell emulsion pools were formed and enumerated for total aerobic organisms, Enterobacteriaceae, and yeast and mold counts. Hy-Line Brown and Hy-Line Silver Brown hens produced eggs with significantly (P < 0.05 and 0.001, respectively) different levels of aerobic organisms dependent on housing system. Eggs from conventional cages had significantly different (P < 0.05) levels of aerobic contamination in relation to hen strain with Hy-Line Silver Brown having the greatest (4.57 log cfu/mL). Hy-Line Brown and Barred Plymouth Rock hens produced eggs with significantly different (P < 0.01) levels of Enterobacteriaceae among housing systems with conventional caged eggs having the lowest level of contamination for the hen strains. There were no differences within each strain among housing systems for yeast and mold contamination. The study shows that hen strain has an effect on egg microbial levels for various housing systems, and egg safety should be considered when making hen strain selections for each housing system.}, number={8}, journal={Poultry Science}, publisher={Elsevier BV}, author={Jones, D.R. and Anderson, K.E.}, year={2013}, month={Aug}, pages={2221–2225} }
 @article{golden_arbona_anderson_2012, title={A comparative examination of rearing parameters and layer production performance for brown egg-type pullets grown for either free-range or cage production}, volume={21}, ISSN={["1056-6171"]}, DOI={10.3382/japr.2011-00370}, abstractNote={SUMMARY Within the last 10 yr, the US egg industry has grown significantly in the use of alternative systems of cage-free and free-range egg production to satisfy consumer demands. Despite the increasing popularity among consumers of alternative management methods, very few studies have been conducted in the United States with the objective of comparing rearing parameters and production performance in alternative systems with those of conventional caged housing. Present knowledge regarding pullet growth records and how alternative production methods influence egg productivity and egg quality is severely limited or is based on research conducted in the late 1940s and early 1950s. Thus, it is imperative that pullet-rearing parameters of current strains, as well as their egg production performance, be assessed in alternative management systems, such as a free-range environment, and that they be compared with those of birds in a traditional caged environment. On the basis of the egg production performance measured in this study, caged hens had better overall egg production and quality characteristics compared with free-range hens, including improved FCR, daily egg masses, production of hen-housed and hen-day eggs, and production of grade A eggs; greater Haugh unit ratings; and decreased mortality rates.}, number={1}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Golden, J. B. and Arbona, D. V. and Anderson, K. E.}, year={2012}, month={Mar}, pages={95–102} }
 @article{anderson_jones_2012, title={Effect of genetic selection on growth parameters and tonic immobility in Leghorn pullets}, volume={91}, ISSN={["0032-5791"]}, DOI={10.3382/ps.2011-01799}, abstractNote={Four genetic stocks of Leghorn pullets were used to evaluate the effects of genetic selection on growth and fearfulness behavior. Three of the stocks were the Ottawa randombred control stocks from 1950 (CS5), 1959 (CS7), and 1972 (CS10). The fourth stock was a 1993 commercial laying stock (CCS) whose ancestors were involved in the formation of the randombred control stocks. Pullets were reared in a brood and grow poultry house with flat deck cages. Each stock was comprised of 840 birds with 21 replicates per strain. Body weight and feed consumption were monitored biweekly. At 16 wk of age, a 20-hen sample from each strain was analyzed for BW, body composition, and tonic immobility. There were significant (P < 0.05) differences among the stocks for BW of 1,403; 1,333; 1,332; and 1,428 g for the CS5, CS7, CS10, and CCS stocks, respectively. Furthermore, significant differences occurred with regard to feed consumption, livability, and frame size. There were no differences among the stocks in tonic immobility. Measurement of circulating corticosterone levels were shown to be significantly (P < 0.05) higher in the CCS stock (7.64 ng/mL) than for both the CS5 (4.50 ng/mL) and CS7 (4.61 ng/mL) stocks, whereas the CS10 stock was intermediate with 6.45 ng/mL. Genetic selection has affected growth parameters, although there appears to be no change in fearfulness behavior but an increase in corticosterone levels in stocks from later years.}, number={3}, journal={POULTRY SCIENCE}, author={Anderson, K. E. and Jones, D. R.}, year={2012}, month={Mar}, pages={765–770} }
 @article{lawrence_jones_yoon_heitschmidt_anderson_2012, title={Improved hairline crack detector and poor shell-quality eggs}, volume={28}, DOI={10.13031/2013.41275}, abstractNote={As more egg processors are moving to in-line processing facilities, human egg graders are having difficulties detecting small hairline-cracks in table eggs. These small hair-line cracks are much harder to detect than larger or older cracks. To aid graders, a modified-pressure imaging system was developed to detect cracks in table eggs. The original system was modified and can now process 20 eggs at a time in batch mode. The eggs are positioned on rollers and held in a sealed clear acrylic chamber. The system utilizes high-intensity white LED lights for illumination and a stepper motor is now used to automate the rotation of the eggs. It also uses a high-resolution monochromatic camera to take images of the eggs. The first image is taken at atmospheric pressure and the second is taken while the chamber undergoes a short, rapid, negative change in pressure. If there is no crack, then there is effectively no difference in the two images. However, if a crack is present, it causes an increase in the intensity of the crack pixels in the negative-pressure image resulting in a significant difference between the two images. This difference (in the form of a ratio) is the basis for identifying a crack. Software then displays the egg images and color-codes each egg as either green (intact) or red (cracked) and highlights any cracks with a contrasting color. Typically, the system uses four sets of images to cover practically all the eggs surface and completes the crack detection in about 40 s. The modified system was tested with poor shell-quality eggs from multiple strains of hens to see if it would induce cracks in these eggs. Analysis of 3279 poor shell-quality eggs (both white and brown), from six strains of pre-molt hens, laid in the heat of the summer, resulted in only one crack caused by the system (0.03%). Thus, it is highly unusual for the system to cause cracks in intact eggs, even eggs with poor shell quality.}, number={1}, journal={Applied Engineering in Agriculture}, author={Lawrence, K. C. and Jones, D. R. and Yoon, S. C. and Heitschmidt, G. W. and Anderson, Kenneth}, year={2012}, pages={153–158} }
 @article{jones_anderson_guard_2012, title={Prevalence of coliforms, Salmonella, Listeria, and Campylobacter associated with eggs and the environment of conventional cage and free-range egg production}, volume={91}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.2011-01795}, DOI={10.3382/ps.2011-01795}, abstractNote={There is a desire by US consumers for eggs produced by hens in alternative production systems. As the retail shell-egg market offers these products to accommodate consumer demands, additional information is needed to ensure processing methodologies result in safe eggs from all egg sources. A study was conducted to determine if there were differences in the prevalence of coliforms, Salmonella, Listeria, and Campylobacter on and within eggs and in the environment of a sister flock of conventional cage and free-range laying hens. Microbial sampling occurred approximately every 6 wk between 20 and 79 wk of age. A random sampling of typical coliform colonies produced 371 viable isolates for biochemical identification. Twenty-nine genera or species of bacteria were identified. There was a significantly greater (P < 0.0001) prevalence of Campylobacter in the free-range nest box swabs compared with that in the free-range grass and conventional cage swab samples (number of positives: 8 nest box, 1 grass, 0 cage). Seven isolates of Listeria innocua were detected with no significant difference in prevalence between the treatments. Isolates were associated with eggshells (2 free-range floor, 1 cage) and the free-range environment (2 nest box, 2 grass). There were 21 Salmonella isolates detected between all sample locations, with no significant difference in the prevalence of Salmonella detection between the treatments. Additional studies are needed to fully understand the effect of alternative production methods on the prevalence of pathogens and coliforms associated with nest-run eggs and the production environment.}, number={5}, journal={Poultry Science}, publisher={Elsevier BV}, author={Jones, D.R. and Anderson, K.E. and Guard, J.Y.}, year={2012}, month={May}, pages={1195–1202} }
 @article{arbona_anderson_hoffman_2011, title={A Comparison of Humoral Immune Function in Response to a Killed Newcastle’s Vaccine Challenge in Caged Vs. Free-range Hy-line Brown Layers}, volume={10}, ISSN={1682-8356}, url={http://dx.doi.org/10.3923/ijps.2011.315.319}, DOI={10.3923/ijps.2011.315.319}, abstractNote={The relationship between immune function and disease risk may be greatly influenced by an organism’s response to chronic stressors including those that are environmentally induced. Measurements of stress-induced immune alterations have previously been made in poultry species by utilizing hematological and immunological indices. To ascertain the effects of alternative layer housing management methods on humoral immune function, Hy-line Brown hens housed on range (n = 15) or in battery style cages (n = 20) were inoculated with a killed Newcastle's vaccine. Blood serum samples were taken prior to injection and for three consecutive weeks following injection to assess antibody production. Antibody production was significantly higher in caged hens in comparison to free-range hens at pre-injection (1.69±0.70 vs. 0.069±0.069) (p<0.0001) and post-injection week one (2.26±0.77 vs. 0.145±0.25) (p<0.0001), week two (8.00±2.98 vs. 4.38±2.94) (p<0.001) and week 3 (9.24±2.56 vs. 6.69±3.86) (p<0.05). Additionally, caged hens exhibited a significantly higher level (p<0.0001) of total antibody production (5.30±0.23) throughout the immune challenge compared to free-range hens (2.82±0.26). Caged hens exhibited significantly higher H:L ratios (2.34±0.86 vs. 1.75±0.57) (p<0.05) during post-injection week 2 which correlated with the greatest difference in antibody production observed between the two groups of hens. This data indicated that environmental management methods utilized in layer hen production may influence both levels of humoral immune function and heterophil:lymphocyte ratios.}, number={4}, journal={International Journal of Poultry Science}, publisher={Science Alert}, author={Arbona, D.V. and Anderson, K.E. and Hoffman, J.B.}, year={2011}, month={Apr}, pages={315–319} }
 @inbook{rollin_mcglone_capper_anderson_engle_2011, place={Boca Raton, Florida}, title={Animal Welfare: Synthesizing Contemporary Animal Agriculture/Engineering and Animal Comfort and Social Responsibility}, booktitle={Animal welfare in animal agriculture : husbandry, stewardship, and sustainability in animal production}, publisher={CRC Press}, author={Rollin, Bernard E and McGlone, John J. and Capper, Judith L. and Anderson, Kenneth and Engle, Terry}, editor={Pond, Wilson G and Bazer, F. W. and Rollin, Bernard EEditors}, year={2011}, pages={147–184} }
 @article{jones_anderson_musgrove_2011, title={Comparison of environmental and egg microbiology associated with conventional and free-range laying hen management}, volume={90}, ISSN={["0032-5791"]}, DOI={10.3382/ps.2010-01139}, abstractNote={Eggs from alternative production practices are a growing niche in the market. Meeting consumer requests for greater diversity in retail egg options has resulted in some unique challenges such as understanding the food safety implications of eggs from alternative production practices. A study was conducted to determine what, if any, differences exist between nest run conventional cage-produced eggs and free range-produced eggs. A sister flock of brown egg layers was maintained in conventional cage and free-range production with egg and environmental sampling every 6 wk from 20 to 79 wk of age. Aerobic, coliform, and yeast and mold populations were monitored. Environmental microbial levels were not always indicative of egg contamination levels. When significant differences (P < 0.05 and P < 0.0001, dependent on season) were observed among treatments for coliforms, shell contamination levels of free-range nest box eggs and free-range floor eggs were always greater than those of conventional cage eggs, which remained low throughout the study (0.42-0.02 log cfu/mL). Shell yeast and mold levels were significantly greater in free-range floor eggs than in free-range nest box eggs and conventional cage eggs throughout the entire study. Egg contents contamination levels were extremely low for all monitored populations and treatments. Season of the year played a role in both environmental and egg microbial levels. Winter had the lowest levels of all populations monitored for all treatments, except for aerobic free-range floor egg shell emulsions, which were increased (3.6 log cfu/mL). Understanding the differences in microbial populations present on conventional cage-produced and free range-produced eggs can lead to the development of effective cleaning procedures, enhancing food safety.}, number={9}, journal={POULTRY SCIENCE}, author={Jones, D. R. and Anderson, K. E. and Musgrove, M. T.}, year={2011}, month={Sep}, pages={2063–2068} }
 @article{anderson_2011, title={Comparison of fatty acid, cholesterol, and vitamin A and E composition in eggs from hens housed in conventional cage and range production facilities}, volume={90}, ISSN={["1525-3171"]}, DOI={10.3382/ps.2010-01289}, abstractNote={The public perceives that the nutritional quality of eggs produced as free range is superior to that of eggs produced in cages. Therefore, this study compared the nutrient content of free-range vs. cage-produced shell eggs by examining the effects of the laboratory, production environment, and hen age. A flock of 500 Hy-Line Brown layers were hatched simultaneously and received the same care (i.e., vaccination, lighting, and feeding regimen), with the only difference being access to the range. The nutrient content of the eggs was analyzed for cholesterol, n-3 fatty acids, saturated fat, monounsaturated fat, polyunsaturated fat, β-carotene, vitamin A, and vitamin E. The same egg pool was divided and sent to 4 different laboratories for analysis. The laboratory was found to have a significant effect on the content of all nutrients in the analysis except for cholesterol. Total fat content in the samples varied (P < 0.001) from a high of 8.88% to a low of 6.76% in laboratories D and C, respectively. Eggs from the range production environment had more total fat (P < 0.05), monounsaturated fat (P < 0.05), and polyunsaturated fat (P < 0.001) than eggs produced by caged hens. Levels of n-3 fatty acids were also higher (P < 0.05), at 0.17% in range eggs vs. 0.14% in cage eggs. The range environment had no effect on cholesterol (163.42 and 165.38 mg/50 g in eggs from caged and range hens, respectively). Vitamin A and E levels were not affected by the husbandry to which the hens were exposed but were lowest at 62 wk of age. The age of the hens did not influence the fat levels in the egg, but cholesterol levels were highest (P < 0.001) at 62 wk of age (172.54 mg/50 g). Although range production did not influence the cholesterol level in the egg, there was an increase in fat levels in eggs produced on the range.}, number={7}, journal={POULTRY SCIENCE}, author={Anderson, K. E.}, year={2011}, month={Jul}, pages={1600–1608} }
 @article{bosquet_peedicayil_maguire_chien_rodriguez_whitaker_petitte_anderson_barnes_shridhar_et al._2011, title={Comparison of gene expression patterns between avian and human ovarian cancers}, volume={120}, ISSN={["1095-6859"]}, url={http://europepmc.org/abstract/med/21093898}, DOI={10.1016/j.ygyno.2010.10.030}, abstractNote={Objectives A putative model of spontaneous cancer has been described in the laying hen that bears significant similarities to human ovarian cancer. Our objective was to characterize and compare the patterns of gene expression in chicken and human forms of this disease. Methods RNA from 20 localized and metastatic ovarian and oviductal chicken tumor samples was isolated, amplified using in vitro transcription, and hybridized against normal ovarian epithelium to a customized cDNA microarray constructed for these studies. Differentially expressed genes were identified for localized ovarian, metastatic ovarian, and oviductal (or tubal) cancer by class comparison using BRB-ArrayTools. Results were validated with semi-quantitative PCR. A gene list (prediction model) constructed with the class prediction tool was used in a human ovarian cancer microarray obtained from the GEO datasets (GSE6008) in order to compare these results across species. Results Class comparison analysis between localized ovarian, metastatic ovarian and oviductal cancer yielded 41 different informative probes that coded for 27 unique genes. Localized ovarian samples clustered between metastatic ovarian and oviductal cancer samples. Using our chicken data as a training set and leaving oviductal samples out of the analysis, we created a prediction model that classified early stage and advanced stage human ovarian cancer gene expression arrays with 78% overall accuracy. Conclusions Gene expression of spontaneous ovarian cancer in the chicken is comparable to gene expression patterns of human ovarian cancer.}, number={2}, journal={GYNECOLOGIC ONCOLOGY}, author={Bosquet, Jesus Gonzalez and Peedicayil, Abraham and Maguire, Jacie and Chien, Jeremy and Rodriguez, Gustavo C. and Whitaker, Regina and Petitte, James N. and Anderson, Kenneth E. and Barnes, H. John and Shridhar, Viji and et al.}, year={2011}, month={Feb}, pages={256–264} }
 @article{anderson_lowman_stomp_chang_2011, title={Duckweed as a Feed Ingredient in Laying Hen Diets and its Effect on Egg Production and Composition}, volume={10}, ISSN={1682-8356}, url={http://dx.doi.org/10.3923/ijps.2011.4.7}, DOI={10.3923/ijps.2011.4.7}, abstractNote={Duckweed, a prolific aquatic plant, can be used for products including: biofuels (ethanol) and animal feeds. Researchers at North Carolina State University have worked for a decade to develop a system to produce high-protein duckweed biomass utilizing the nutrient-rich effluent from anaerobic digestion of swine wastewater. This aspect of the project was to evaluate a feeding trial utilizing duckweed materials as a protein source in laying hen feed. The nutrient and energy composition of the Duckweed grown in these conditions was determined, then the impact of duckweed in a commercial layer diet on egg production and feed conversion was evaluated. The duckweed samples analyzed contained 29.05% CP, 25.08% C Fiber and 695 kcal/kg AMEn based on a feeding trial with marker. The analysis was used to formulate a layer diet containing 12.6% duckweed. Both the Control (C) and Duckweed (D) diets were formulated to be Iso- nitrogenous (18.1% Crude Protein) and Iso-caloric (2930 kcal/kg). Sixty Hy-Line, w-36 hens were randomly divided into 4 replicates each containing 15 hens from 76-88 wks of age, 2 replicates were placed on the C Diet and the remaining 2 were fed the D diet. Feed consumption and egg production monitored daily and each wk one days collection was analyzed for USDA Grades, haugh unit, shell strength, vitelline membrane strength and yolk color. On wks 3, 7 and 11 whole 6 egg pooled samples were collected and sent in for nutrient composition laboratory analysis. The D diet had no impact on the hen performance over that of the C diet group, 71.1 and 69.5% hen-day production, respectively. There was a significant increase in th e percent Grade B eggs in the hens fed the D by 2% over the C hens. Surprisingly, there was no difference in the nutrient composition of the eggs except for Omega 3 levels which were 0.06 % higher (P<0.0001) than in the C hens. The results indicate that duckweed can be fed at a 12.6% inclusion rate and not impact the performance of laying hens and may be a means of enhancing Omega 3 levels in eggs.}, number={1}, journal={International Journal of Poultry Science}, publisher={Science Alert}, author={Anderson, K.E. and Lowman, Z. and Stomp, Anne-Marie and Chang, Jay}, year={2011}, month={Jan}, pages={4–7} }
 @article{anderson_jenkins_2011, title={Effect of Rearing Dietary Regimen, Feeder Space and Density on Egg Production, Quality and Size Distribution in Two Strains of Brown Egg Layers}, volume={10}, ISSN={1682-8356}, url={http://dx.doi.org/10.3923/ijps.2011.169.175}, DOI={10.3923/ijps.2011.169.175}, abstractNote={Step-Up Protein (SUP) rearing regimens can reduce Feed Consumption (FC) and Body Weight (BW), while still resulting in pullets with equal or superior egg production and egg mass to pullets grown on a Step-Down Protein (SDP) program. Egg weight has been reduced due to SUP programs, presumably due to the reduced BW at sexual maturity. Because BW is reduced by SUP regimens and a slight lowering of FC, BW and EW may be economically advantageous. Therefore, the objective of this experiment was to evaluate the impact of SUP regimens on brown-egg layer rearing program on subsequent productivity and the effect of feeder space and density on performance. Two brown-egg strains, Hy-Line Brown (HB) and the H and N "Brown Nick" (BN) were grown on three different dietary regimens, i.e. a "normal" SDP regimen, a SU P regimen: low energy starter for 9 wk (SUP9) and a SUP regimen: low energy starter for 12 wk (SUP12). The SUP9 and SUP12 feeding regimens resulted in significantly lower BW and feed conversion and shorter sternum length, than the SDP regimen. Egg production was not significantly different among the 3 regimens, but feed conversion was lower while livability was highest in the SUP12 reared hens. Feeder space of 13.6 cm resulted in poorer feed conversion for the SUP12 reared hens. Density per hen of 482 cm resulted in 2}, number={3}, journal={International Journal of Poultry Science}, publisher={Science Alert}, author={Anderson, K.E. and Jenkins, P.K.}, year={2011}, month={Mar}, pages={169–175} }
 @article{carver_barnes_anderson_petitte_whitaker_berchuck_rodriguez_2011, title={Reduction of Ovarian and Oviductal Cancers in Calorie-Restricted Laying Chickens}, volume={4}, ISSN={["1940-6215"]}, url={http://europepmc.org/abstract/med/21325563}, DOI={10.1158/1940-6207.capr-10-0294}, abstractNote={Abstract}, number={4}, journal={CANCER PREVENTION RESEARCH}, author={Carver, Donna K. and Barnes, H. John and Anderson, Kenneth E. and Petitte, James N. and Whitaker, Regina and Berchuck, Andrew and Rodriguez, Gustavo C.}, year={2011}, month={Apr}, pages={562–567} }
 @article{anderson_2010, title={Effects of Dietary Regimens and Brown-Egg Pullet Strain on Growth and Development}, volume={9}, ISSN={1682-8356}, url={http://dx.doi.org/10.3923/ijps.2010.205.211}, DOI={10.3923/ijps.2010.205.211}, abstractNote={This study consisted of; two strains of brown-egg pullets, the Hy-Line (HB) and HN a Step-up Protein Regimen (SUP9) comprised of a 12% CP Starter, 0-9 week, 16% CP Grower 2, 10-16 week and 18% CP Grower 1, 17-18 week and a Step-up Protein Regimen (SUP12) comprised of a 12% CP Starter, 0-12 week, 16% CP Grower 2, 13- 16 week and 18% CP Grower 1, 17-18 week. The pullets were housed in an environmentally controlled rearing facility with trideck battery cages. Feed consumption and body weights were measured bi-weekly and mortality was recorded daily. At 17 week of age a sample of 20 pullets from each strain and regimen combination were randomly selected and brought to the laboratory for body composition analysis. At 18 week the HB and BN strains only differed in livability with the HB having a 4.2% greater (p<0.05) liveability than the BN pullets. There was a stepwise reduction (p<0.05) in total protein intake from the SDP, SUP9 and SUP12, however, energy, Ca, P and lysine consumption were comparable. The SUP9 and SUP12 feeding regimens resulted in significantly (p<0.05) lower BW than the SDP regimen pullets. The SUP12 regimen significantly reduced sternum length below that obtained with the SDP or SUP9 program 11.0 vs. 11.2 and 11.3 cm, respectively. Tibial breaking strength was no different between the strains or regimens. This study shows that pullets reared on SUP regimens would have lower body weights with few differences in bod y composition percentages. Indicating that reduced dietary protein and energy would result in smaller pullets with comparable body composition.}, number={3}, journal={International Journal of Poultry Science}, publisher={Science Alert}, author={Anderson, K.E.}, year={2010}, month={Mar}, pages={205–211} }
 @article{kerth_curtis_willian_kerth_anderson_2010, title={Evaluation of fatty acids and proteins in eggs from cage and range laying hens}, volume={89}, number={Supplement 1}, journal={Poultry Science}, author={Kerth, L.K. and Curtis, P.A. and Willian, K.R. and Kerth, C.R. and Anderson, K.E.}, year={2010}, pages={293–294} }
 @article{gast_jones_anderson_guraya_guard_holt_2010, title={In vitro penetration of Salmonella Enteritidis through yolk membranes of eggs from 6 genetically distinct commercial lines of laying hens}, volume={89}, ISSN={["1525-3171"]}, DOI={10.3382/ps.2009-00440}, abstractNote={Although deposition of Salmonella Enteritidis inside yolks is less common than deposition in albumen or on the vitelline (yolk) membrane in naturally contaminated eggs laid by infected hens, bacterial migration into the yolk to reach its nutrient-rich contents could lead to extensive multiplication. The present study used an in vitro egg contamination model to assess the ability of small initial numbers of Salmonella Enteritidis to penetrate the vitelline membrane and multiply inside yolks of eggs laid by 6 genetically distinct commercial lines of hens during 24 h of storage at 30 degrees C. Eggs from each line were tested at 4 different hen ages by inoculation of approximately 100 cfu of Salmonella Enteritidis onto the outside of the vitelline membranes of intact yolks in plastic centrifuge tubes and then adding back the albumen into each tube before incubation. Overall, the frequency of penetration of Salmonella Enteritidis into the yolk contents of eggs from individual lines of hens ranged from 30 to 58% and the mean concentration of Salmonella Enteritidis in yolk contents after incubation ranged from 0.8 to 2.0 log(10) cfu/mL. For both of these parameters, values for one hen line were significantly higher than for 2 other lines, but no other differences were observed. Hen age did not have a significant effect on egg yolk penetration by Salmonella Enteritidis. These results indicate that opportunities for the migration and growth of small initial numbers of Salmonella Enteritidis to attain more dangerous levels inside contaminated eggs during storage at warm temperatures can sometimes vary between different lines of laying hens.}, number={8}, journal={POULTRY SCIENCE}, author={Gast, R. K. and Jones, D. R. and Anderson, K. E. and Guraya, R. and Guard, J. and Holt, P. S.}, year={2010}, month={Aug}, pages={1732–1736} }
 @article{hawkridge_wysocky_petitte_anderson_mozdziak_fletcher_horowitz_muddiman_2010, title={Measuring the intra-individual variability of the plasma proteome in the chicken model of spontaneous ovarian adenocarcinoma}, volume={398}, ISSN={["1618-2650"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77957867631&partnerID=MN8TOARS}, DOI={10.1007/s00216-010-3979-y}, abstractNote={The domestic chicken (Gallus domesticus) has emerged as a powerful experimental model for studying the onset and progression of spontaneous epithelial ovarian cancer (EOC) with a disease prevalence that can exceed 35% between 2 and 7 years of age. An experimental strategy for biomarker discovery is reported herein that combines the chicken model of EOC, longitudinal plasma sample collection with matched tissues, advanced mass spectrometry-based proteomics, and concepts derived from the index of individuality (Harris, Clin Chem 20: 1535–1542, 1974). Blood was drawn from 148 age-matched chickens starting at 2.5 years of age every 3 months for 1 year. At the conclusion of the 1 year sample collection period, the 73 birds that remained alive were euthanized, necropsied, and tissues were collected. Pathological assessment of resected tissues from these 73 birds confirmed that five birds (6.8%) developed EOC. A proteomics workflow including in-gel digestion, nanoLC coupled to high-performance mass spectrometry, and label-free (spectral counting) quantification was used to measure the biological intra-individual variability (CVW) of the chicken plasma proteome. Longitudinal plasma sample sets from two birds within the 73-bird biorepository were selected for this study; one bird was considered “healthy” and the second bird developed late-stage EOC. A total of 116 proteins from un-depleted plasma were identified with 80 proteins shared among all sample sets. Analytical variability (CVA) of the label-free proteomics workflow was measured using a single plasma sample analyzed five times and was found to be ≥CVW in both birds for 16 proteins (20%) and in either bird for 25 proteins (31%). Ovomacroglobulin (ovostatin) was found to increase (p < 0.001) over a 6 month period in the late-stage EOC bird providing an initial candidate protein for further investigation.}, number={2}, journal={ANALYTICAL AND BIOANALYTICAL CHEMISTRY}, author={Hawkridge, Adam M. and Wysocky, Rebecca B. and Petitte, James N. and Anderson, Kenneth E. and Mozdziak, Paul E. and Fletcher, Oscar J. and Horowitz, Jonathan M. and Muddiman, David C.}, year={2010}, month={Sep}, pages={737–749} }
 @article{hawkridge_wysocky_petitte_anderson_mozdziak_fletcher_horowitz_muddiman_2010, title={Measuring the intra-individual variability of the plasma proteome in the chicken model of spontaneous ovarian adenocarcinoma (vol 398, pg 737, 2010)}, volume={398}, ISSN={["1618-2642"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77957848897&partnerID=MN8TOARS}, DOI={10.1007/s00216-010-4107-8}, number={4}, journal={ANALYTICAL AND BIOANALYTICAL CHEMISTRY}, author={Hawkridge, Adam M. and Wysocky, Rebecca B. and Petitte, James N. and Anderson, Kenneth E. and Mozdziak, Paul E. and Fletcher, Oscar J. and Horowitz, Jonathan M. and Muddiman, David C.}, year={2010}, month={Oct}, pages={1835–1835} }
 @article{jones_musgrove_anderson_thesmar_2010, title={Physical quality and composition of retail shell eggs}, volume={89}, ISSN={["0032-5791"]}, DOI={10.3382/ps.2009-00315}, abstractNote={There are a number of specialty shell eggs available to consumers in the US retail market. A survey consisting of white and brown large shell eggs with various production and nutritional differences (traditional, cage-free, free-roaming, pasteurized, nutritionally enhanced, and fertile) was conducted to determine if physical quality and compositional differences exist. Identical brands of eggs were purchased from the same retail outlets on 3 occasions (replicates) in a single city. The average range of time from processing to purchase for all eggs was 7.67 to 25.33 d, with traditional white eggs in retail having the shortest time. Haugh unit values ranged from 66.67 (cage-free, docosahexaenoic acid, and n-3 enhanced) to 84.42 (traditional white). Albumen height followed a similar pattern. Egg weight was greater for brown eggs (61.12 vs. 58.85 g). Brown eggs also had greater static compression shell strength than white eggs (4,130.61 vs. 3,690.31 g force). Vitelline membrane strength was greatest for traditional brown eggs (2.24 g force). Percentage of total solids and crude fat was greatest in the cage-free, n-3-enhanced white eggs (25.07 and 11.71%, respectively). Although significant differences were found between white and brown shell eggs and production methods, average values for quality attributes varied without one egg type consistently maintaining the highest or lowest values.}, number={3}, journal={POULTRY SCIENCE}, author={Jones, D. R. and Musgrove, M. T. and Anderson, K. E. and Thesmar, H. S.}, year={2010}, month={Mar}, pages={582–587} }
 @article{caudill_curtis_anderson_kerth_oyarazabal_jones_musgrove_2010, title={The effects of commercial cool water washing of shell eggs on Haugh unit, vitelline membrane strength, aerobic microorganisms, and fungi}, volume={89}, ISSN={["1525-3171"]}, DOI={10.3382/ps.2009-00316}, abstractNote={Current egg washing practices use wash water temperatures averaging 49 degrees C and have been found to increase internal egg temperature by 6.7 to 7.8 degrees C. These high temperatures create a more optimal environment for bacterial growth, including Salmonella Enteritidis if it is present. Salmonella Enteritidis is the most common human pathogen associated with shell eggs and egg products. Its growth is inhibited at temperatures of 7.2 degrees C and below. The objective of this study was to determine if commercially washing eggs in cool water would aid in quickly reducing internal egg temperature, preserving interior egg quality, and slowing microbial growth. During 3 consecutive days, eggs were washed using 4 dual-tank wash water temperature schemes (HH = 49 degrees C, 49 degrees C; HC = 49 degrees C, 24 degrees C; CC = 24 degrees C, 24 degrees C; CH = 24 degrees C, 49 degrees C) at 2 commercial processing facilities. A 10-wk storage study followed, in which vitelline membrane strength, Haugh unit, and aerobic microorganisms and fungi (yeasts and molds) were monitored weekly. As storage time progressed, average Haugh unit values declined 14.8%, the average force required to rupture the vitelline membrane decreased 20.6%, average numbers of bacteria present on shell surfaces decreased 11.3%, and bacteria present in egg contents increased 39.5% during storage. Wash water temperature did not significantly affect Haugh unit values, vitelline membrane strength, or the numbers of aerobic microorganisms and fungi within the shell matrices of processed eggs. Results of this study indicate that incorporating cool water into commercial shell egg processing, while maintaining a pH of 10 to 12, lowers postprocessing egg temperatures and allows for more rapid cooling, without causing a decline in egg quality or increasing the presence of aerobic microorganisms and fungi for approximately 5 wk postprocessing.}, number={1}, journal={POULTRY SCIENCE}, author={Caudill, A. B. and Curtis, P. A. and Anderson, K. E. and Kerth, L. K. and Oyarazabal, O. and Jones, D. R. and Musgrove, M. T.}, year={2010}, month={Jan}, pages={160–168} }
 @article{anderson_mozdziak_petitte_2010, title={The impact of scheduled cage cleaning on older hens (Gallus gallus)}, volume={39}, ISSN={["1548-4475"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77953926452&partnerID=MN8TOARS}, DOI={10.1038/laban0710-210}, abstractNote={Researchers are increasingly using the domestic hen (Gallus gallus) as an animal model for ovarian cancer. The authors analyzed mortality rates of two large flocks of older hens that were being used for ovarian adenocarcinoma studies. All hens were fed the same maintenance diets, though some hens in each flock received experimental chemopreventive treatments. Per the request of a collaborating institution, partway through the study, the authors started to remove the hens in one of the flocks for cage changing once every 4 weeks. After the authors began cleaning some of the hens' cages, the mortality rate in this flock increased significantly. Throughout the study, within each flock, hens in the treatment and control groups had similar mortality rates. These results suggest that regularly cleaning the cages of older hens may not promote better welfare or improve flock mortality.}, number={7}, journal={LAB ANIMAL}, author={Anderson, Kenneth E. and Mozdziak, Paul E. and Petitte, James N.}, year={2010}, month={Jul}, pages={210–215} }
 @article{arbona_anderson_hoffman_2009, title={Health and production in improved cage designs}, volume={10}, number={4}, journal={International Journal of Poultry Science}, author={Arbona, D.V. and Anderson, K.E. and Hoffman, J.B.}, year={2009}, pages={348–354} }
 @article{kretzschmar-mccluskey_curtis_anderson_berry_kerth_2009, title={Influence of hen age and strain on eggshell exterior, eggshell interior with membranes, and egg contents of microflora, and on Salmonella incidence during a single production cycle}, volume={18}, ISSN={["1537-0437"]}, DOI={10.3382/japr.2008-00104}, abstractNote={SUMMARY Salmonella enterica serovar Enteritidis (SE) infection in humans has been associated with the consumption of raw or undercooked eggs. This study was conducted to determine if increasing hen age influenced the total microflora counts or the incidence of Salmonella spp. on the eggshell surface, inside the shell, or in the egg contents. Eggs from Hy-Line W-98 and Bovans White layer strains were sampled once a month over a 12-mo period from 17 to 65 wk of age. The layers were reared in accordance with the guidelines set by the 35th North Carolina Layer Performance and Management Test. Bacteria on the eggshell exterior, in the shell interior and membranes, and in the egg contents were enumerated to obtain total aerobic counts and were tested for the prevalence of SE. Sampling of the eggs began with rinsing the exterior of the shell to recover microorganisms from the surface. The pooled shell rinsates of 9 eggs per layer strain times 5 replicates were expressed as the exterior counts. Egg content sampling included both the yolk and albumen components, as well as the chalazae. Of 120 total egg pools, only 1 positive Salmonella sample was detected from the exterior and 1 was detected from the interior shell and membranes. Hen age significantly (P < 0.05) affected the total microbial loads on the egg components tested. Exterior shell populations increased at wk 32. Interior shell and membrane counts increased significantly (P < 0.05) over time, increasing by 2 log cfu/mL of sample during the 12-mo cycle. Egg contents microflora data showed an increase from nondetectable to 1 log cfu/mL of sample at 36, 40, and 65 wk of age. Although Salmonella serotypes Ohio and Infantis were discovered in the study, no SE-positive samples were found for this trial. Although hen age did play a significant role in the increase of microflora, it had little effect on the incidence of SE.}, number={4}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Kretzschmar-McCluskey, V. and Curtis, P. A. and Anderson, K. E. and Berry, W. D. and Kerth, L. K.}, year={2009}, month={Dec}, pages={665–670} }
 @article{hakim_barry_barnes_anderson_petitte_whitaker_lancaster_wenham_carver_turbov_et al._2009, title={Ovarian Adenocarcinomas in the Laying Hen and Women Share Similar Alterations in p53, ras, and HER-2/neu}, volume={2}, ISSN={["1940-6215"]}, url={http://europepmc.org/abstract/med/19174584}, DOI={10.1158/1940-6207.CAPR-08-0065}, abstractNote={Abstract}, number={2}, journal={CANCER PREVENTION RESEARCH}, author={Hakim, Amy A. and Barry, Catherine P. and Barnes, H. John and Anderson, Kenneth E. and Petitte, James and Whitaker, Regina and Lancaster, Jonathan M. and Wenham, Robert M. and Carver, Donna K. and Turbov, Jane and et al.}, year={2009}, month={Feb}, pages={114–121} }
 @article{anderson_2009, title={Overview of natural and organic egg production: Looking back to the future}, volume={18}, ISSN={["1056-6171"]}, DOI={10.3382/japr.2008-00119}, abstractNote={Abstract The US egg industry has grown dramatically in the past, with a significant component of that growth focusing on alternative production systems such as cage-free or range egg production. Constituents of this growth involving intensive egg production create uncertainty in relation to the future because of concerns about the impact of the cage environment on laying hen well-being. Both the commercial egg production sector and small producers using heritage strains of chickens, in flocks ranging in size from 100 to 3,000 hens, are responding by producing eggs in both cage-free and range settings. However, one of the current issues is that our knowledge base of how these alternative production methods influence egg performance and quality characteristics is limited to research studies that were conducted in the late 1940s and early 1950s. This information was collected with specific breeds, and not with modern lines of poultry that have been selected for very high rates of egg production. Therefore, an examination of alterative laying hen husbandry practices in the context of the current knowledge base would provide beneficial information to identify how these husbandry and feeding practices translate to modern strains of laying hens under cage-free or range production. Research on range or cage-free production done in controlled settings is limited, and additional studies relevant to egg producers wishing to expand cage-free and range egg production are needed.}, number={2}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Anderson, K. E.}, year={2009}, pages={348–354} }
 @article{vaughn_holt_moore_gast_anderson_2008, title={Crop Immune Response Post-Salmonella Enteritidis Challenge in Eight Commercial Egg-Layer Strains and Specific-Pathogen-Free White Leghorn Chickens}, volume={52}, ISSN={["1938-4351"]}, DOI={10.1637/7982-040907-Reg}, abstractNote={Abstract The crop immune response against Salmonella Enteritidis (SE) challenge in eight commercial egg-layer strains (five white-egg layer and three brown-egg layer) and specific-pathogen-free (SPF) White Leghorn (WL) hens was investigated. Pre- and post-SE challenge mucosal immune responses within the crops were evaluated. Commercial layers and SPF WL hens were orally challenged with 108 CFU/ml SE PT13a and SE nalR PT13, respectively. Crop lavage samples were collected at weekly intervals from day 0 (pre-challenge) to day 25–27 postinfection (PI), and bacteriological examination was performed to monitor progression of SE infection. Crop lavage samples were analyzed for SE-lipopolysaccharide (LPS)–specific IgA using enzyme-linked immunosorbent assay (ELISA). H&E-stained slides of crop sections from day 34 PI and uninfected controls were assessed for lymphoid tissue via light microscopy. Lymphoid areas were graded based on morphology, size, and cellularity using a score 0 to 5 scale. The 0 to 5 (low to high) numerical values represented progressive increases in size and cellular density of lymphoid tissue. Bacterial culture results showed the highest percentage of SE-positive crop lavage samples from all hen groups at day 5–6 PI and day 11–12 PI. A progressive decline in percentage of SE-positive crop lavage samples did occur as time PI lengthened; however, at day 25–27 PI SE persisted in crop lavage samples from SPF WL hens and three commercial white-egg layer strains. A marked increase in SE-LPS-specific IgA was measured in crop lavage samples between day 0 and day 11–12 PI for all hen groups. Crop SE-LPS-specific IgA response remained elevated above day 0 baseline for the duration of the experiment. Well-defined score 3 to 5 lymphoid tissue aggregates were observed in crop tissue sections harvested at day 34 PI. Comparison of crop sections determined a 1.2–4.0 times increase in ratio of lymphoid tissue in day 34 PI SE-challenged hens vs. uninfected control hens.}, number={1}, journal={AVIAN DISEASES}, author={Vaughn, L. E. and Holt, P. S. and Moore, R. W. and Gast, R. K. and Anderson, K. E.}, year={2008}, month={Mar}, pages={79–87} }
 @article{kretzschmar-mccluskey_curtis_anderson_kerth_berry_2008, title={Influence of hen age and molting treatments on shell egg exterior, interior, and contents microflora and Salmonella prevalence during a second production cycle}, volume={87}, ISSN={["0032-5791"]}, DOI={10.3382/ps.2007-00433}, abstractNote={The objective of this study was to determine if increasing hen age and 3 different molting treatments influenced the total microflora counts or the prevalence of Salmonella spp. on the exterior of the egg shell, within the interior shell, or in the contents. Eggs from Hy-Line W-98 and Bovans White layer strains were sampled approximately every 28 d from 70 to 114 wk of age, with the molting period from 66 to 70 wk of age. Layers were utilized from the 35th North Carolina Layer Performance and Management Test and managed under identical husbandry practices. This study consisted of nonfasted, nonmolted, and feed-restricted treatments with the use of 135 eggs per layer strain, for a total of 270 eggs sampled per period. The exterior, interior shell, and contents were spiral plated onto plate count agar to calculate the total aerobic counts. Additional preenrichment, enrichment, conformational, and biochemical procedures were performed to test for the presence of Salmonella spp. Hen age and molting treatment significantly (P < 0.05) affected the microbial loads on all 3 egg components. Exterior, interior, yolk, and albumen counts increased during the molt period to as much as 1 log unit higher than the highest countable plate, which was 10(5). Exterior, interior, and contents counts significantly increased (P < 0.05) during period 15, with a significant increase (P < 0.05) in the interior also in period 14, and in the contents in periods 14 and 17. There were a total of 360 egg pools, and of those, 4 were positive Salmonella samples. Both the interior and exterior shell components and 2 of the 3 molting treatments had positive samples. Of these positives, 4 were confirmed as Salmonella Braenderup. Three positives were associated with the interior component, whereas 1 positive was associated with the exterior shell component. Three of the 4 samples were related to the nonfasted treatment, whereas the remaining positive was found in the non-molted treatment.}, number={10}, journal={POULTRY SCIENCE}, author={Kretzschmar-McCluskey, V. and Curtis, P. A. and Anderson, K. E. and Kerth, L. K. and Berry, W. D.}, year={2008}, month={Oct}, pages={2146–2151} }
 @article{koelkebeck_patterson_anderson_darre_carey_ahn_ernst_kuney_jones_2008, title={Temperature sequence of eggs from oviposition through distribution: Processing - Part 2}, volume={87}, ISSN={["1525-3171"]}, DOI={10.3382/ps.2007-00239}, abstractNote={The Egg Safety Action Plan released in 1999 raised questions concerning egg temperature used in the risk assessment model. Therefore, a national study was initiated to determine the internal and external temperature sequence of eggs from oviposition through distribution. Researchers gathered data from commercial egg production, shell egg processing, and distribution facilities. The experimental design was a mixed model with 2 random effects for season and geographic region and a fixed effect for operation type (inline or offline). For this report, internal and external egg temperature data were recorded at specific points during shell egg processing in the winter and summer months. In addition, internal egg temperatures were recorded in pre- and postshell egg processing cooler areas. There was a significant season x geographic region interaction (P < 0.05) for both surface and internal temperatures. Egg temperatures were lower in the winter vs. summer, but eggs gained in temperature from the accumulator to the postshell egg processing cooler. During shell egg processing, summer egg surface and internal temperatures were greater (P < 0.05) than during the winter. When examining the effect of shell egg processing time and conditions, it was found that 2.4 and 3.8 degrees C were added to egg surface temperatures, and 3.3 and 6.0 degrees C were added to internal temperatures in the summer and winter, respectively. Internal egg temperatures were higher (P < 0.05) in the preshell egg processing cooler area during the summer vs. winter, and internal egg temperatures were higher (P < 0.05) in the summer when eggs were (3/4) cool (temperature change required to meet USDA-Agricultural Marketing Service storage regulation of 7.2 degrees C) in the postshell egg processing area. However, the cooling rate was not different (P > 0.05) for eggs in the postshell egg processing cooler area in the summer vs. winter. Therefore, these data suggest that season of year and geographic location can affect the temperature of eggs during shell egg processing and should be a component in future assessments of egg safety.}, number={6}, journal={POULTRY SCIENCE}, author={Koelkebeck, K. W. and Patterson, P. H. and Anderson, K. E. and Darre, M. J. and Carey, J. B. and Ahn, D. U. and Ernst, R. A. and Kuney, D. R. and Jones, D.}, year={2008}, month={Jun}, pages={1187–1194} }
 @article{anderson_patterson_koelkebeck_darre_carey_ahn_ernst_kuney_jones_2008, title={Temperature sequence of eggs from oviposition through distribution: Transportation - Part 3}, volume={87}, ISSN={["0032-5791"]}, DOI={10.3382/ps.2007-00236}, abstractNote={The Egg Safety Action Plan released in 1999 raised many questions concerning egg temperature used in the risk assessment model. Therefore, a national study by researchers in California, Connecticut, Georgia, Iowa, Illinois, North Carolina, Pennsylvania, and Texas was initiated to determine the internal and external temperature sequence of eggs from oviposition through distribution. Researchers gathered data from commercial egg production, processing, and distribution facilities. The experimental design was a mixed model with random effects for season and a fixed effect for duration of the transport period (long or short haul). It was determined that processors used refrigerated transport trucks (REFER) as short-term storage (STS) in both the winter and summer. Therefore, this summary of data obtained from REFER also examines the impact of their use as STS. Egg temperature data were recorded for specific loads of eggs during transport to point of resale or distribution to retailers. To standardize data comparisons between loads, they were segregated between long and short hauls. The summer egg temperatures were higher in the STS and during delivery. Egg temperature was not significantly reduced during the STS phase. Egg temperature decreases were less (P < 0.0001) during short delivery hauls 0.6 degrees C than during long hauls 7.8 degrees C. There was a significant season x delivery interaction (P < 0.05) for the change in the temperature differences between the egg and ambient temperature indicated as the cooling potential. This indicated that the ambient temperature during long winter deliveries had the potential to increase egg temperature. The REFER used as STS did not appreciably reduce internal egg temperature. These data suggest that the season of year affects the temperature of eggs during transport. Eggs are appreciably cooled on the truck, during the delivery phase, which was contrary to the original supposition that egg temperatures would remain static during refrigerated transport. These data indicate that refrigerated transport should be a component in future assessments of egg safety.}, number={6}, journal={POULTRY SCIENCE}, author={Anderson, K. E. and Patterson, P. H. and Koelkebeck, K. W. and Darre, M. J. and Carey, J. B. and Ahn, D. U. and Ernst, R. A. and Kuney, D. R. and Jones, D. R.}, year={2008}, month={Jun}, pages={1195–1201} }
 @article{patterson_koelkebeck_anderson_darre_carey_ahn_ernst_kuney_jones_2008, title={Temperature sequence of eggs from oviposition through distribution: production - Part 1}, volume={87}, ISSN={["1525-3171"]}, DOI={10.3382/ps.2007-00242}, abstractNote={During Egg Safety Action Plan hearings in Washington, DC, many questions were raised concerning the egg temperature (T) used in the risk assessment model. Therefore, a national study was initiated to determine the T of eggs from oviposition through distribution. In part 1; researchers gathered data on internal and surface egg T from commercial egg production facilities. An infrared thermometer was used to rapidly measure surface T, and internal T was determined by probing individual eggs. The main effects were geographic region (state) and season evaluated in a factorial design. Egg T data were recorded in the production facilities in standardized comparisons. Regression analysis (P < 0.0001) showed that the R(2) (0.952) between infrared egg surface T and internal T was very high, and validated further use of the infrared thermometer. Hen house egg surface and internal T were significantly influenced by state, season, and the state x season interaction. Mean hen house egg surface T was 27.3 and 23.8 degrees C for summer and winter, respectively, with 29.2 and 26.2 degrees C for egg internal T (P < 0.0001). Hen house eggs from California had the lowest surface and internal T in winter among all the states (P < 0.0001), whereas the highest egg surface T were recorded during summer in North Carolina, Georgia, and Texas, and the highest internal T were recorded from Texas and Georgia. Cooling of warm eggs following oviposition was significantly influenced by season, state, and their interaction. Egg internal T when 3/4 cool was higher in summer vs. winter and higher in North Carolina and Pennsylvania compared with Iowa. The time required to 3/4 cool eggs was greater in winter than summer and greater in Iowa than in other states. These findings showed seasonal and state impacts on ambient T in the hen house that ultimately influenced egg surface and internal T. More important, they showed opportunities to influence cooling rate to improve internal and microbial egg quality.}, number={6}, journal={POULTRY SCIENCE}, author={Patterson, P. H. and Koelkebeck, K. W. and Anderson, K. E. and Darre, M. J. and Carey, J. B. and Ahn, D. U. and Ernst, R. A. and Kuney, D. R. and Jones, D. R.}, year={2008}, month={Jun}, pages={1182–1186} }
 @article{ruiz_ruiz_gernat_grimes_murillo_wineland_anderson_maguire_2008, title={The effect of quicklime (CaO) on litter condition and broiler performance}, volume={87}, ISSN={["0032-5791"]}, DOI={10.3382/ps.2007-00101}, abstractNote={High levels of phosphorus and pathogens in runoff are 2 major concerns following manure applications to fields. Phosphorus losses from fields following manure applications have been linked to the solubility of phosphorus in manure; therefore, by decreasing manure phosphorus solubility, a decrease in phosphorus loss in runoff should be apparent. The objective of this research was to develop a process using quicklime that would result in reduced phosphorus solubility and bacteria counts in broiler litter. The 4 litter treatments evaluated were T1, new wood shavings without the addition of quicklime; T2, used, untreated broiler litter; T3, used litter with 10% quicklime (based on the weight of the litter); and T4, used litter with 15% quicklime (based on the weight of the litter). Body weight, cumulative feed consumption, and feed conversion (feed:BW) were determined on a weekly basis through 42 d of age. Mortality was recorded daily. Carcass weights and percentages of carcass yield without giblets were determined prechill. Litter pH, total phosphorus, nitrogen, soluble phosphorus, litter moisture (%), and total plate counts were measured for each litter treatment on d 7 and 42 after bird placement. No significant differences were found for BW, feed consumption, feed conversion, mortality, carcass weight, or carcass yield. No breast or footpad blisters were observed. On d 7, 15% quicklime had higher (P < 0.001) pH (11.2) when compared with the other treatments. Percentages of phosphorus and nitrogen were lower (P < 0.001) for new wood shavings in comparison with the used litter treatments. Soluble phosphorus (ppm) was lower (P < 0.001) for 15% quicklime (2.75) when compared with new wood shavings (42.2), untreated broiler litter (439.2), and 10% quicklime (35.0). Although not significant, 15% quicklime had lower total plate counts (cfu/g) in comparison with the other treatments on d 1 and 10 postmixing and at 7 d after bird placement. Litter conditions on d 42 after bird placement were similar. We concluded that the use of quicklime as a treatment for broiler litter would initially reduce nitrogen and soluble phosphorus and bacteria counts without negatively affecting bird productivity.}, number={5}, journal={POULTRY SCIENCE}, author={Ruiz, V. and Ruiz, D. and Gernat, A. G. and Grimes, J. L. and Murillo, J. G. and Wineland, M. J. and Anderson, K. E. and Maguire, R. O.}, year={2008}, month={May}, pages={823–827} }
 @article{jackson_anderson_ashwell_petitte_mozdziak_2007, title={CA125 expression in spontaneous ovarian adenocarcinomas from laying hens}, volume={104}, ISSN={0090-8258}, url={http://dx.doi.org/10.1016/j.ygyno.2006.07.024}, DOI={10.1016/j.ygyno.2006.07.024}, abstractNote={Currently, there is not a fully characterized model for human ovarian cancer; however, 2- to 4-year-old laying hens spontaneously develop ovarian tumors. CA125 expression is a hallmark of ovarian cancer in women. The major objective of this study was to characterize the in vitro growth of avian ovarian tumor cells, and CA125 expression in avian ovarian tumors.Immunohistochemistry was employed to evaluate CA125 expression in avian ovarian tumor tissue. A high temperature antigen retrieval step was an essential part of the CA125 staining procedure. In vitro growth curves were constructed for avian ovarian cancer cells. Western blotting was used to estimate the size of the CA125 reactive protein and to confirm CA125 expression.The growth of avian tumors in culture fits a sigmoidal curve for cell growth and suggests a cell cycle time of 28 h. The tumors taken from the chicken stained positive for CA125. Approximately 90% of cells isolated from avian ovarian tumors also stained positive for CA125. Western blots show a band of approximately 25 kDa when immunodetected with CA125.Similar to human ovarian tumors, chicken ovarian tumors express CA125. Cultured chicken ovarian cancer cells express CA125 and CA125 expression does not appear to change with time in culture.}, number={1}, journal={Gynecologic Oncology}, publisher={Elsevier BV}, author={Jackson, Emily and Anderson, Ken and Ashwell, Chris and Petitte, James and Mozdziak, Paul E.}, year={2007}, month={Jan}, pages={192–198} }
 @article{anderson_havenstein_2007, title={Effects of alternative Molting programs and population on layer performance: Results of the thirty-fifth North Carolina layer performance and management test (vol 16, pg 965, 2007)}, volume={16}, number={4}, journal={Journal of Applied Poultry Research}, author={Anderson, K. E. and Havenstein, G. B.}, year={2007}, pages={656–657} }
 @article{anderson_havenstein_2007, title={Effects of alternative molting programs and population on layer performance: Results of the thirty-fifth North Carolina layer performance and management test}, volume={16}, ISSN={["1537-0437"]}, DOI={10.1093/japr/16.3.365}, abstractNote={SUMMARY A study involving 7 white-egg and 3 brown-egg commercial layer strains was conducted at the North Carolina Piedmont Research Station to assess the effects cage population 3-bird vs. 4-bird cages and alternative molt programs on performance through 113 wk of age (791 d). The flock was divided into 3 groups; not molted (NM), maintained in continuous production; molted using feed restriction (FR), an industry-type 14-d feed withdrawal molting program initiated at 463 d of age; and molted using a nonfasted/anorexic program (NF), in which an ad libitum supply of a low protein, low energy molt feed was provided. Productivity, egg size, and egg quality were monitored at 28-d periods throughout the test providing the performance data for the white-egg and brown-egg strains with regard to these management factors. Detailed results by strain are available on the following Web site: http://www.ces.ncsu.edu/depts/poulsci/tech_info.html#layer. The performance for the 3-bird or 4-bird cage groups for either type of layer was similar, except that birds in 4-bird cages had higher feed consumption in the first production phase than did the birds in 3-bird cages. In the same time period the white-egg birds in the 3-bird cages had a greater percentage of cracked eggs and a smaller percentage of Grade A large eggs than those in 4-bird cages. No differences were observed in egg income for the 2 population sizes for either type of layer. However, due to their higher feed consumption, the white egg birds in the 4-bird cages had higher feed cost per hen for the first cycle, which was offset by the egg income component due to their increased production rate. The molted layers outperformed the nonmolted layers for both types of layers in terms of overall income over feed costs. The FR molted hens, under a program thathastraditionallybeenusedbycommercialproducers,outperformedNF-moltedhens,indicating that further refinements are needed to make the NF program economically competitive with the FR molting program.}, number={3}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Anderson, K. E. and Havenstein, G. B.}, year={2007}, pages={365–380} }
 @article{anderson_jones_davis_jenkins_2007, title={Effects of genetic selection on behavioral profiles of single comb white Leghorn hens through two production cycles}, volume={86}, ISSN={["1525-3171"]}, DOI={10.1093/ps/86.9.1814}, abstractNote={Four layer genetic stocks consisting of 3 Ottawa control strains (5, 7, and 10) and a commercial laying stock (CCS) were utilized to evaluate potential changes in behavioral profiles due to the effects of genetic selection through 2 production cycles. The Ottawa strains were started as random bred strains from the crosses of several popular commercial layers in 1950, 1959, and 1972, and the commercial strain used herein was from calendar year 1993, and its ancestors were involved in the formation of all of the random bred strains. The behavior study utilized 2 replicates from each strain that contained 4 cages, 6 hens/cage, for a total of 192 hens. Behavioral observations were recorded on 2 consecutive days beginning at 22 wk of age and every 28 d thereafter during the first production cycle, the molt period, and the second production cycle through 90 wk of age and periodic feather and Hansen's test scores recorded. Behavior profiles were similar between the control strains and the CCS, indicating that long-term genetic selection by commercial egg-type breeding firms to enhance production parameters has had no impact on laying strain behavior patterns. Appetitive behaviors were not affected by strain. During the molt, hens had reduced (P < 0.05) feeding and drinking frequencies in comparison with those observed during the first and second cycles. The data indicated that hens pecked inedible objects at a greater (P < 0.0001) frequency during the first cycle and molt than during the second cycle. Fearfulness scores were only influenced by production phase with the molt having the highest (P < 0.01) score of 3.46. Strain or production phase did not influence the frequency of aggressive and submissive acts.}, number={9}, journal={POULTRY SCIENCE}, author={Anderson, K. E. and Jones, D. R. and Davis, G. S. and Jenkins, P. K.}, year={2007}, month={Sep}, pages={1814–1820} }
 @article{koelkebeck_anderson_2007, title={Molting layers - Alternative methods and their effectiveness}, volume={86}, ISSN={["1525-3171"]}, DOI={10.1093/ps/86.6.1260}, abstractNote={The molting of commercial layers has been under increased scrutiny by animal rights groups, who have said that this practice is highly stressful and one which negatively affects the welfare of the hen due to the initial period of fasting that has been used to stop egg production. In recent years, there has been a recognized need to develop practical alternatives to molting layers other than the use of fasting. Thus, the University of Illinois, University of Nebraska, North Carolina State University, and the University of California have all researched this area. In all of these studies, the methods involved comparing a normal fasting method (i.e., 5 to 13 d), to feeding low-energy and protein diets using ingredients such as wheat middlings, soybean hulls, and corn or diets with graded levels of added salt and without salt (University of Nebraska, University of California). The molt period (28 d) included full-feeding of these diets. In these studies, postmolt production performance for the nonfeed withdrawal techniques was comparable to the fasting method. Several researchers have also evaluated the behavioral repertoire of laying hens, which includes feeding, drinking, comfort, social, reproductive, and anti-predator behaviors. In addition, related behaviors such as aggression, escape-avoidance, and submission have been of particular interest as potential indicators of welfare during molting. In these studies, genetic selection, strain, density, or molt program do not appear to adversely influence the behavioral patterns during the molt. The behavior patterns displayed during a molt program appear consistent with the response to physiological changes that layers experience and do not appear to compromise the welfare status of the hens. Appetitive behaviors were not affected by strain but were affected by production phase and molting. Strain or production phase did not influence the frequency of aggressive and submissive acts. Thus, the use of alternative nonfeed withdrawal molting methods provide comparable laying hen well-being and may enhance the transition from a productive to a resting state.}, number={6}, journal={POULTRY SCIENCE}, author={Koelkebeck, K. W. and Anderson, K. E.}, year={2007}, month={Jun}, pages={1260–1264} }
 @article{anderson_koelkebeck_2007, title={Realistic views concerning poultry welfare}, volume={86}, ISSN={["0032-5791"]}, DOI={10.1093/ps/86.6.1251}, abstractNote={The animal welfare (rights) issue we face today is not one that will be resolved through research or factual knowledge. It is an emotional issue that resides on philosophical beliefs that are often associated with the religion of an individual or his or her lack thereof. Individuals who oppose the use of animals for research, food, companionship, etc., based on personal feelings or philosophies, may never change their minds based on scientific facts. However, the opportunity we have is the minds of those people who have not yet made up their mind. We can instill in them a respect for life and a clear understanding that it is okay to utilize animals for companionship and for food production provided the animals are maintained under acceptable and reasonable conditions and that they are cared for in a humane manner. This issue will continue to be a tough battle, because, from past experience, animal rightists will sometimes stage animal abuse to prove their viewpoint. We must also realize that due to the nature of humans, not everyone who is responsible for animals, in both research and production settings, will properly care for them. Animal mistreatment or abuse is a major black eye for everyone, and it is always caused by individuals who do not handle animals in a humane and proper manner. However, we have to admit that humanity has reverted to some very deplorable states in history.}, number={6}, journal={POULTRY SCIENCE}, author={Anderson, K. E. and Koelkebeck, K. W.}, year={2007}, month={Jun}, pages={1251–1252} }
 @article{li_payne_santos_levine_anderson_sheldon_2007, title={Salmonella Populations and Prevalence in Layer Feces from Commercial High-Rise Houses and Characterization of the Salmonella Isolates by Serotyping, Antibiotic Resistance Analysis, and Pulsed Field Gel Electrophoresis}, volume={86}, ISSN={0032-5791}, url={http://dx.doi.org/10.1093/ps/86.3.591}, DOI={10.1093/ps/86.3.591}, abstractNote={Salmonella species are recognized as a major cause of foodborne illnesses that are closely associated with the consumption of contaminated poultry and egg products. The objectives of this study were to evaluate the Salmonella populations and prevalence in layer feces during the laying cycle and molting of the hen and to characterize the layer fecal Salmonella isolates by serotyping, antibiotic resistance analysis, and pulsed field gel electrophoresis. Fecal samples were collected from a commercial layer complex consisting of 12 houses. Composite fecal samples across each row were collected as a function of bird age [18 wk (at placement), 25 to 28 wk (first peak of production cycle), 66 to 74 wk (molting), and 75 to 78 wk (second peak of production cycle)]. Bird ages and molting practice did not significantly affect (P > 0.05) Salmonella populations with an average of 1.25, 1.27, 1.20, and 1.14 log most probable number/g for the 18-, 25- to 28-, 66- to 74-, and 75- to 7-wk birds, respectively. However, the 18-wk birds had the highest prevalence of Salmonella (55.6%), followed by the 25- to 28-wk birds (41.7%), 75- to 78-wk birds (16.7%), and 66- to 74-wk birds (5.5%). Of the 45 Salmonella isolates characterized, the most predominant serovar was Salmonella Kentucky (62%). Thirty-five percent of the Salmonella isolates were resistant to at least 1 antibiotic. As expected, considerable genetic diversity was observed within and across the different serovars.}, number={3}, journal={Poultry Science}, publisher={Elsevier BV}, author={Li, X. and Payne, J.B. and Santos, F.B. and Levine, J.F. and Anderson, K.E. and Sheldon, B.W.}, year={2007}, month={Mar}, pages={591–597} }
 @article{keener_mcavoy_foegeding_curtis_anderson_osborne_bush_2006, title={Effect of testing temperature on internal egg quality measurements}, volume={85}, ISSN={0032-5791}, url={http://dx.doi.org/10.1093/ps/85.3.550}, DOI={10.1093/ps/85.3.550}, abstractNote={The objective of this study was to determine the effect of egg testing temperature on quality measurements of shell eggs. The quality measurements compared included 3 Haugh unit (HU) devices (electronic Haugh, tripod Haugh, and Haugh meter), egg weight, albumen height, albumen width, albumen index, yolk width, yolk height, yolk index, percentage of thin albumen, and vitelline membrane strength at 3 temperatures of 5, 13, and 23 degrees C from 2 strains of laying hens (Hyline W36 and Bovans White) at 2 storage times. The HU measurements averaged 72.44 at time zero and 59.99 at 7 wk. At 7 wk for all devices, HU values decreased 6 units with increased temperature (P < 0.05). The electronic Haugh and tripod Haugh devices gave equal measurements for all testing conditions. The Haugh meter gave equal values at 5 degrees C for fresh eggs but lower HU at higher temperatures and 7 wk storage. Thus, it is recommended that egg testing temperature be reported when HU are measured. Coefficient of variation generally increased for all HU methods with increasing temperature. Although there was a proportionately different amount of thin albumen detected between the strains of laying hens, no significant difference was seen in HU. From the evaluated methods for measuring quality, the electronic Haugh, which electronically measures albumen height and calculates HU, provided the lowest coefficient of variation, was sensitive to quality loss, and gave the highest quality measurement (5 degrees C).}, number={3}, journal={Poultry Science}, publisher={Elsevier BV}, author={Keener, KM and McAvoy, KC and Foegeding, JB and Curtis, PA and Anderson, KE and Osborne, JA and Bush, DJ}, year={2006}, month={Mar}, pages={550–555} }
 @inbook{zeidler_anderson_samimi_2006, place={Peachtree Corners, GA}, edition={I-P and S-I Editions}, title={Eggs and Egg Products}, ISBN={978-1-931862-86-8}, booktitle={ASHRAE Handbook - Refrigeration}, publisher={American Society of Heating, Refrigeration, and Air-Conditioning Engineers, Inc}, author={Zeidler, G. and Anderson, K.E. and Samimi, M.}, year={2006}, pages={21–1-21–13} }
 @article{maguire_hesterberg_gernat_anderson_wineland_grimes_2006, title={Liming poultry manures to decrease soluble phosphorus and suppress the bacteria population}, volume={35}, ISSN={["1537-2537"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-33646558633&partnerID=MN8TOARS}, DOI={10.2134/jeq2005.0339}, abstractNote={ABSTRACT}, number={3}, journal={JOURNAL OF ENVIRONMENTAL QUALITY}, author={Maguire, R. O. and Hesterberg, D. and Gernat, A. and Anderson, K. and Wineland, M. and Grimes, J.}, year={2006}, pages={849–857} }
 @inbook{anderson_2004, title={Chickens: Layer Reproduction Management}, ISBN={9780429178061}, url={http://dx.doi.org/10.1201/9781482276664-68}, DOI={10.1201/9781482276664-68}, booktitle={Encyclopedia of Animal Science}, publisher={CRC Press}, author={Anderson, Kenneth E.}, year={2004}, month={Nov}, pages={225–228} }
 @article{keener_anderson_curtis_foegeding_2004, title={Determination of cooling rates and carbon dioxide uptake in commercially processed shell eggs using cryogenic carbon dioxide gas}, volume={83}, ISSN={["0032-5791"]}, DOI={10.1093/ps/83.1.89}, abstractNote={The ability to rapidly cool shell eggs to 7 degrees C is important in the prevention of Salmonella Enteritidis (SE) growth. In addition, quality may also be maintained longer from rapid cooling of shell eggs. A commercial cryogenic CO2 egg cooling unit was designed and installed in a commercial egg processing facility. This unit was installed on a packer head to rapidly cool eggs individually prior to packaging. The objective of this study was to determine cooling rates and CO2 gas changes that result from rapidly cooling eggs using this commercial cryogenic egg cooling system and subsequent storage for 15 wk. Results indicated that cryogenic CO2 cooling quickly cooled shell eggs in approximately 45 min, whereas traditional cooling required from 19 to 116 h. CO2 uptake into the albumen was greater in cryogenically cooled eggs (2.11 mg/g) than in traditionally cooled eggs (1.81 mg/g) immediately after processing. No differences were observed in albumen CO2 content after 2 wk of storage; at 10 wk statistically greater CO2 content remained in the cryogenically cooled eggs (1.75 mg/g) compared with the traditionally cooled eggs (1.60 mg/g). These results suggest that a large amount of CO2 enters the egg during the cryogenic cooling process but is quickly lost during storage. Beyond 10 wk of storage, the albumen CO2 content in cryogenically cooled eggs was higher than in the traditionally cooled eggs suggesting chemical changes may have occurred in the albumen.}, number={1}, journal={POULTRY SCIENCE}, author={Keener, KM and Anderson, KE and Curtis, PA and Foegeding, JB}, year={2004}, month={Jan}, pages={89–94} }
 @article{anderson_davis_jenkins_carroll_2004, title={Effects of bird age, density, and molt on behavioral profiles of two commercial layer strains in cages}, volume={83}, ISSN={["0032-5791"]}, DOI={10.1093/ps/83.1.15}, abstractNote={Two commercial strains, Hy-Line W-36 and DeKalb XL, were moved to a laying house at 18 wk of age. They were housed 6 hens/layer cage at 2 densities (361 and 482 cm2/bird) with 2 replications each per strain/density combination. The high-density treatment contained 24 hens/replication and the low-density treatment contained 18 hens/replication for a total of 168 hens. Production parameters were measured during the first egg production cycle, the molt period, and the first 4 wk of the second lay cycle (20 to 68 wk of age). Behavioral observations were taken during 2 consecutive d at 26, 34, 43, 51, 62, 64, and 68 wk of age to examine behavioral patterns. Modified Hansen's tests were conducted concurrently to provide indication of the fearfulness levels of hens at the various stages of production. The production characteristics were similar for both strains. The hens kept at the higher density had lower (P < 0.01) hen-day production and (P < 0.05) daily egg mass. Appetitive behaviors were not affected by strain or density but were affected by the age of the hen and by molting. During the molt, feeding and drinking behavioral acts were fewer (P < 0.05) at 0.018 and 0.013 acts per bird/min, respectively, and standing behavior was highest. The results indicated that the frequencies of pecking inedible objects during the molt period were similar to the frequencies at 26 and 34 wk. Hens performed more acts of standing, and crouching and had lower frequency of movement during the molt. Those kept at a low density performed more movement acts. Feather pecking decreased as hens aged and increased when they molted but was not affected by strain or density. The frequency of aggression and submissive acts was significantly lower during the molt period. Behaviors were affected by strain, density, bird age, and molting; however, the patterns and number of aggressive acts did not increase to compromise the welfare status of the hens. Behaviors during the molt appeared consistent with mechanisms for conservation of body reserves.}, number={1}, journal={POULTRY SCIENCE}, author={Anderson, KE and Davis, GS and Jenkins, PK and Carroll, AS}, year={2004}, month={Jan}, pages={15–23} }
 @article{jones_curtis_anderson_jones_2004, title={Microbial contamination in inoculated shell eggs: II. Effects of layer strain and egg storage}, volume={83}, ISSN={["0032-5791"]}, DOI={10.1093/ps/83.1.95}, abstractNote={Three Ottawa control strains and a current commercial laying stock were reared and housed in the same environment. Eggs were collected at 5 different hen ages throughout the 2 production cycles of the flock. The eggs were inoculated with Salmonella Enteritidis (SE), Pseudomonas fluorescens (PF), a combination of the 2, or sterile buffered peptone water and stored up to 5 wk. After storage at room temperature, contamination levels were determined for the exterior surface, air cell, egg contents, and within the shell. Interior, egg contents, and shell contamination levels of SE and PF increased with storage time. There were no apparent increases in the infectivity of SE or PF in the presence of the other organism. PF was a poor survivor on the shell surface under these storage conditions. Throughout the 5-wk storage, eggs from control strain 10 maintained their microbial integrity more effectively. Eggs from control strain 5 and the current commercial stock were more easily contaminated than the other strains. These data suggest that genetic selection has altered microbiological defenses of the eggs produced.}, number={1}, journal={POULTRY SCIENCE}, author={Jones, DR and Curtis, PA and Anderson, KE and Jones, FT}, year={2004}, month={Jan}, pages={95–100} }
 @article{anderson_tharrington_curtis_jones_2004, title={Shell characteristics of eggs from historic strains of Single Comb White Leghorn chickens and the relationship of egg shape to shell strength}, volume={3}, ISBN={1682-8356}, DOI={10.3923/ijps.2004.17.19}, abstractNote={The effect of long term genetic selection on shell characteristics was determined by analyzing eggs acquired from Agriculture Canada: Ottawa Control Strain 5, from a 1950 base population; 7, from a 1959 population; and 10, from a 1972 population. H&N "Nick Chick" 1993 commercial strain was also included because it shares genetic ancestry with the three historic strains. Eggs were collected beginning at 28 wk of age, then every 4 wk through the end of the study at 86 wk of the laying cycle and egg weight, egg height, egg width, shell weight, shell thickness, egg specific gravity, and shell breaking force measured. The relationship of egg shape and weight as factors affecting shell strength were also investigated. Significant differences (P < 0.05) were found between strains for egg shape and a progressive increase in weight and surface area of eggs from the 1950 strain to the current strain. The shape index indicates that the current strain has increased egg size with the greatest increase seen in egg width. The mean breaking force of eggs from the current strain was higher (P< 0.05) than the other strain's eggs with no strain differences in percent shell weight, shell thickness, or specific gravity. A decline in breaking force, percent shell weight, and specific gravity was observed among all the strains over the production period. The results from this study suggest that genetic selection has produced larger eggs that are rounder in shape.}, number={1}, journal={International Journal of Poultry Science}, author={Anderson, Kenneth and Tharrington, J. B. and Curtis, P. A. and Jones, F. T.}, year={2004}, pages={17} }
 @article{musgrove_jones_northcutt_curtis_anderson_fletcher_cox_2004, title={Survey of shell egg processing plant sanitation programs: Effects on non-egg-contact surfaces}, volume={67}, ISSN={["0362-028X"]}, DOI={10.4315/0362-028X-67.12.2801}, abstractNote={Sanitation standard operating procedures (SSOPs) are an integral component of process control and are often the first step in the implementation of food safety regulations. The objective of this study was to assess and compare the efficacies of sanitation programs used in a variety of shell egg processing facilities. In-line, off-line, and mixed operations were evaluated. Sixteen direct or indirect egg contact surfaces were sampled in various shell egg processing facilities in the southeast United States. Samples were collected at the end of a processing day (POST) and again the next morning before operations began (PRE). Total aerobic plate counts (APCs) were obtained and Enterobacteriacae were enumerated. No significant differences (P > 0.05) between POST and PRE bacterial counts were found for the 16 sampling sites. In general, high APCs were found on the wall of the recirculating water tank both POST and PRE. The APCs for the rewash belt were considerably high for all plants sampled. APCs were also high for the vacuum loaders. APCs for washers and washer brushes were relatively low for most plants sampled. PRE and POST levels of plant sanitation, as determined by direct microbial plating, did not differ significantly. At this point, it is difficult to draw definitive conclusions about how rigid SSOPs should be for the shell egg processing industry.}, number={12}, journal={JOURNAL OF FOOD PROTECTION}, author={Musgrove, MT and Jones, DR and Northcutt, JK and Curtis, PA and Anderson, KE and Fletcher, DL and Cox, NA}, year={2004}, month={Dec}, pages={2801–2804} }
 @article{davis_anderson_jones_2004, title={The effects of different beak trimming techniques on plasma corticosterone and performance criteria in single comb White Leghorn hens}, volume={83}, ISSN={["1525-3171"]}, DOI={10.1093/ps/83.10.1624}, abstractNote={DeKalb XL chicks were given a beak trim at 6 d of age (6DP) with a 2.8-mm gauge and a beak trim at 11 wk (11WB) with a block cut approximately 2 mm anterior to the nasal openings. Corticosterone (CS) levels of the 6DP treatment were (P < or = 0.01) elevated above nontrimmed CS levels at 2 h posttrim; and BW and feed consumption (FC) of the 6DP were depressed until 8 wk of age. At 11 wk of age, CS of the 11WB treatment was (P < or = 0.02) elevated above controls at 1, 2, 8, and 5 wk posttrim. The 11WB treatment resulted in a decrease in FC and a reduction in BW at 12, 14, and 16 wk of age, whereas there were no differences among treatments in livability during the pullet phase. At 72 wk of age, FC of the nontrimmed controls was greater than both beak trimmed treatments, and both beak trimmed treatments had greater hen housed eggs, percentage hen day egg production, and percentage livability. Both beak trimmed treatments resulted in better egg income, feed cost per hen, and net income (NI). The 6DP and 11WB beak trim treatments resulted in an improvement of NI per hen of 1.48 dollars and 1.86 dollars, respectively. In addition, both beak trimmed treatments exhibited better feather score and Hansen's test (fearfulness). It was concluded that pullets and hens could adapt to the physiological stress of beak trimming and out perform, during a lay phase, controls whose beaks were not trimmed.}, number={10}, journal={POULTRY SCIENCE}, author={Davis, GS and Anderson, KE and Jones, DR}, year={2004}, month={Oct}, pages={1624–1628} }
 @article{jones_northcutt_musgrove_curtis_anderson_fletcher_cox_2003, title={Survey of Shell Egg Processing Plant Sanitation Programs: Effects on Egg Contact Surfaces}, volume={66}, ISSN={0362-028X 1944-9097}, url={http://dx.doi.org/10.4315/0362-028x-66.8.1486}, DOI={10.4315/0362-028x-66.8.1486}, abstractNote={To successfully implement a hazard analysis critical control point plan, prerequisite programs are essential. Sanitation standard operating procedures are an important part of such a plan and can reduce contamination levels so that food safety and quality are not adversely affected. Noncontact surfaces in the shell egg processing plants can serve as a reservoir of cross-contamination. The objective of this study was to assess the efficacy of sanitation programs used in a variety of shell egg processing facilities (in-line, off-line, and mixed operations). Fourteen different noncontact surfaces were sampled in nine commercial facilities across the southeastern United States. Non-egg-contact surfaces were defined as those where the shell egg does not come into direct contact with the surface or with the fluid from that surface. Gauze pads soaked in sterile phosphate-buffered saline were used for sampling at the end of a processing day (POST) and again the next morning prior to operations (PRE). Aerobic plate counts (APCs) and numbers of Enterobacteriaceae were determined. No significant differences (P > 0.05) were found between POST and PRE counts for either population recovered from the 14 sampling sites. Only samples from the floor under the farm belts, nest-run loader, washers, and packer heads were reduced by 1 log CFU/ml of rinsate for APCs or Enterobacteriaceae counts. APCs of more than 10(4) CFU/ml of rinsate were recovered from many samples. Highest APCs were found on the floor under the farm belt and on shelves of the nest-run carts. High APCs were found on the wheel surface for off-line carts and on the loading dock floor. Highest Enterobacteriaceae counts were found in samples from the floor, drain, and nest-run egg cart shelves. A lack of significant difference between POST and PRE counts indicates that current sanitation programs could be improved. These data suggest that traffic patterns for the movement of eggs and materials through the plant should be reevaluated so that cross-contamination is reduced.}, number={8}, journal={Journal of Food Protection}, publisher={International Association for Food Protection}, author={Jones, D. R. and Northcutt, J. K. and Musgrove, M. T. and Curtis, P. A. and Anderson, K. E. and Fletcher, D. L. and Cox, N. A.}, year={2003}, month={Aug}, pages={1486–1489} }
 @inbook{rodriguez_walmer_cline_krigham_whitaker_isner_lessey_mcmahon_marks_petitte_et al._2002, title={Biologic Effects of Progestins on Ovarian Epithelium: Cancer Prevention Through Apoptosis}, ISBN={9780198508267}, booktitle={Ovarian Cancer}, publisher={Oxford University Press}, author={Rodriguez, G.C. and Walmer, D. and Cline, M. and Krigham, H. and Whitaker, R. and Isner, P.D. and Lessey, B. and McMahon, C. and Marks, J. and Petitte, J. and et al.}, editor={Jacobs, I.J. and Shepard, J.H. and Oram, D.H. and Blackett, A.D. and Luesley, D.M. and Hudson, C.HEditors}, year={2002}, pages={161–170} }
 @article{jones_tharrington_curtis_anderson_keener_jones_2002, title={Effects of cryogenic cooling of shell eggs on egg quality}, volume={81}, ISSN={["0032-5791"]}, DOI={10.1093/ps/81.5.727}, abstractNote={This study was conducted to investigate the effects of cryogenic cooling on shell egg quality. Gaseous nitrogen (GN), liquid nitrogen (LN), and gaseous carbon dioxide (GC) were utilized to rapidly cool eggs in a commercial egg processing facility and were compared to traditional cooling (TC). A modified food freezer was attached to existing egg processing equipment in order to expose eggs to the selected cryogen. In Experiment 1, eggs were treated with GN, LN, and TC then stored and tested over 10 wk. Experiment 2 eggs were treated (GC and TC) and evaluated for 12 wk. Quality factors that were measured included Haugh units, vitelline membrane strength and deformation at rupture, and USDA shell egg grades for quality defects. Haugh unit values were greater for cryogenically treated eggs as compared to traditionally cooled eggs (Experiment 1: 73.27, GN; 72.03, LN; and 71.4, TC and Experiment 2: 74.42, GC and 70.18, TC). The percentage of loss eggs in the GN treatment was significantly (P < 0.01) greater than those of the LN and TC treatments. Vitelline membrane strength was greater for the cryogenically cooled eggs versus traditional processing. Vitelline membrane breaking strength decreased over storage time. Vitelline membrane deformation at rupture was significantly (P < 0.05) greater for the cryogenically cooled eggs compared to the traditional eggs in each experiment. Use of the technology could allow for egg quality to be maintained for a longer time, which could increase international markets and potentially lead to extended shelf lives.}, number={5}, journal={POULTRY SCIENCE}, author={Jones, DR and Tharrington, JB and Curtis, PA and Anderson, KE and Keener, KM and Jones, FT}, year={2002}, month={May}, pages={727–733} }
 @inbook{zeidler_anderson_samimi_stadelman_yang_2002, place={Atlanta, GA}, edition={I-P and S-I Editions}, title={Eggs and Egg Products}, ISBN={9781931862004}, booktitle={ASHRAE Handbook: Refrigeration}, publisher={American Society of Heating, Refrigeration, and Air-Conditioning Engineers, Inc}, author={Zeidler, G. and Anderson, K.E. and Samimi, M. and Stadelman, W.J. and Yang, T.}, year={2002} }
 @article{jones_anderson_curtis_jones_2002, title={Microbial contamination in inoculated shell eggs: I. Effects of layer strain and hen age}, volume={81}, ISSN={["0032-5791"]}, DOI={10.1093/ps/81.5.715}, abstractNote={Three Ottawa control strains and a current commercial laying stock were reared and housed under identical environmental and management conditions. Eggs were collected from each strain when hens were 32, 45, 58, 71, and 84 wk of age. The eggs were inoculated with Salmonella enteritidis (SE), Pseudomonasfluorescens (PF), or a combination of the two. After storage at 26 C, bacterial counts were obtained from the exterior shell surfaces (rinse), air cell, egg contents, and shell structure. SE and PF survived at different rates on the shell surface with as much as a 1 log difference during a given collection period. Egg content counts tended to be higher than eggshell counts in PF, whereas the opposite was true for SE. These data suggest that PF is a primary invader of eggs that is more capable of contaminating egg contents through the shell membranes than SE. The PF and SE data suggest that bacterial contamination of air cells, shells, and egg contents is more easily achieved in eggs from older hens than from younger hens. There were also differences between the strains. Control Strain 10 consistently maintained a lower level of contamination for both organisms in each sampling location. The overall results of this study suggest that genetic selection has altered the ability of eggs to resist microbial contamination and that screening for microbial integrity should be considered in the selection process among the laying egg breeders.}, number={5}, journal={POULTRY SCIENCE}, author={Jones, DR and Anderson, KE and Curtis, PA and Jones, FT}, year={2002}, month={May}, pages={715–720} }
 @article{davis_anderson_2002, title={The effects of feeding the direct-fed microbial, PrimaLac, on growth parameters and egg production in Single Comb White Leghorn hens}, volume={81}, ISSN={["0032-5791"]}, DOI={10.1093/ps/81.6.755}, abstractNote={Two commercial strains of Single Comb White Leghorn hens, HyLine W-36 and DeKalb XL, were reared separately as pullet flocks in an enclosed, environmentally controlled brood-grow house with three banks of quad-deck cages (310 cm2 per bird). There were 1,800 hens of each strain, which were divided into two groups, control feed and a direct-fed microbial (DFM) feed treatment. During the pullet-rearing phase to 18 wk of age, the DeKalb birds had greater parameters of growth and overall feed cost than the HyLine birds. The overall feed cost of the DFM treatment was $0.02 per bird greater than controls. However, the DFM-treated feed improved the livability of the DeKalb birds by 2.68%. At 18 wk of age, 3,528 hens were transferred to an enclosed, mechanically ventilated layer house. The two strains were placed in two differently sized quad-deck layer cages with seven birds per cage; the cage sizes were 35.56 cm x 60.96 cm (2,267.73 cm2 or 310 cm2 per bird) and 14 cm x 32 cm (2,890.32 cm2 or 413 cm2 per bird). There were a total of 144 replications with each strain and DFM treatment combination made up of 36 replications equally divided between the high and low density cages. At 70 wk of age, hens receiving the DFM treatment exhibited greater mean egg weights (61.72 g) and percentages of extra large eggs (XLE, 52.06%) compared to that of controls (61.12 g and 48.98%, respectively). The treatment of 310 cm2/hen DFM produced the least (P < or = 0.05) large eggs; however, this treatment group produced the most (P < or = 0.05) XLE. The use of DFM resulted in a shift from smaller to larger eggs. Regardless of density, the DFM hens had lower (P < or = 0.05) feed cost (FC) compared to FC of the controls (a savings of $0.46/bird between the DFM and control in the 310 cm2 /hen treatment and a $0.83 savings/bird between the DFM and control in the 413 cm2/hen treatment). It was concluded that PrimaLac can improve egg size and lower feed costs, regardless of the bird density used in the present study.}, number={6}, journal={POULTRY SCIENCE}, author={Davis, GS and Anderson, KE}, year={2002}, month={Jun}, pages={755–759} }
 @article{bell_patterson_koelkebeck_anderson_darre_carey_kuney_zeidler_2001, title={Egg marketing in national supermarkets: Egg quality - Part 1}, volume={80}, ISSN={["0032-5791"]}, DOI={10.1093/ps/80.4.383}, abstractNote={Two surveys were conducted to determine the quality of eggs offered to consumers in large supermarkets in various regions of the US. The first survey was conducted in California (CA) in 1994 and included 38 samples of large (L) and extra large (XL) white eggs in 15 markets. Individual eggs were weighed, candled, and broken out for Haugh unit (HU) determination. Regional differences in age of eggs, the number of eggs below 55 HU, and the percentage of cracked eggs were observed. The second survey was conducted in California (CA), Illinois (IL), Pennsylvania (PA), Texas (TX), North Carolina (NC), and New England (NE). This study included brown and white eggs and samples from 115 stores in 38 cities. Significant age, egg weight, HU, and cracked egg differences were observed between states. Brown and white eggs were different relative to age and HU, but egg weights and cracked eggs were statistically the same. The two surveys, 1994 and 1996, within CA demonstrated very similar measurements when L-white eggs were compared.}, number={4}, journal={POULTRY SCIENCE}, author={Bell, DD and Patterson, PH and Koelkebeck, KW and Anderson, KE and Darre, MJ and Carey, JB and Kuney, DR and Zeidler, G}, year={2001}, month={Apr}, pages={383–389} }
 @article{koelkebeck_bell_carey_anderson_darre_2001, title={Egg marketing in national supermarkets: Products, packaging, and prices - Part 3}, volume={80}, ISSN={["0032-5791"]}, DOI={10.1093/ps/80.4.396}, abstractNote={As part of a national retail egg quality study, the variety of shell eggs and egg products offered for sale, type of packaging, and price relationships were compared in five major metropolitan regions. A total of 81 stores in 28 cities were sampled in California (CA), Illinois (IL), North Carolina (NC), Texas (TX), and New England (NE). Data were recorded for the variety of brands, sizes, white or brown shell eggs, specialty eggs, liquid or frozen eggs, carton sizes, package labeling and coding, and price relationships of shell eggs, liquid, and frozen egg products displayed for sale. The total variety of shell eggs displayed per store was the greatest for CA and NE stores. Stores in CA and TX offered more (P < 0.05) variety of white shell eggs than did stores in the other states, whereas stores in NE displayed the greatest variety (P < 0.05) of brown shell eggs. The average number of liquid and frozen egg products was highest (P < 0.05) for NC stores. Packaging type, USDA labeling, and carton coding differed somewhat among states. The price per one dozen cartons of all white shell egg sizes was highest (P < 0.05) in CA stores, and the average liquid plus frozen egg product prices were higher in CA and NE stores compared to the other states. However, the ratio of liquid and frozen product prices to all large shell egg prices was among the lowest for CA and NC stores. These data indicate that product selection, packaging, and consumer prices for shell eggs and egg products varied considerably across five separate regions of the country.}, number={4}, journal={POULTRY SCIENCE}, author={Koelkebeck, KW and Bell, DD and Carey, JB and Anderson, KE and Darre, MJ}, year={2001}, month={Apr}, pages={396–400} }
 @article{patterson_koelkebeck_bell_carey_anderson_darre_2001, title={Egg marketing in national supermarkets: Specialty eggs - Part 2}, volume={80}, ISSN={["0032-5791"]}, DOI={10.1093/ps/80.4.390}, abstractNote={Large eggs promoted as having one or more features beyond conventional white or brown shell eggs (specialty eggs) were evaluated for quality and price in a national retail study. Subtypes of specialty eggs included: nutritionally altered eggs, organic eggs, fertile eggs, eggs from welfare-managed hens, or hens fed all-vegetable diets. Extension Poultry Specialists in California (CA), Connecticut, Illinois, North Carolina, Pennsylvania and Texas conducted a survey of egg quality and price and compared 246 dozen specialty eggs with 390 dozen conventional white shell eggs during the summer of 1996. Age of the eggs based on carton dating indicated specialty eggs were older (16.5 d) than white eggs (11.7 d). Average egg weights for specialty compared to white were 60.2 and 59.6 g, respectively. Interior egg quality evaluations including albumen height, Haugh units (HU), and percentage HU <55, indicated white eggs were superior (5.0 mm, 67.5, and 10.6%, respectively) compared to specialty eggs (4.7 mm, 63.8, and 16.3%). Although the percentage of cracked eggs was similar between specialty and white eggs (5.4 and 5.7%), the percentage of leakers was threefold higher for the specialty eggs (1.0 vs. 0.3%). Egg price was substantially higher for the specialty eggs, averaging $2.18/dozen with a range from 0.88 to $4.38, compared to white eggs, averaging $1.23/dozen and ranging from 0.39 to $2.35.}, number={4}, journal={POULTRY SCIENCE}, author={Patterson, PH and Koelkebeck, KW and Bell, DD and Carey, JB and Anderson, KE and Darre, MJ}, year={2001}, month={Apr}, pages={390–395} }
 @article{jones_anderson_davis_2001, title={The effects of genetic selection on production parameters of single comb white leghorn hens}, volume={80}, ISSN={["0032-5791"]}, DOI={10.1093/ps/80.8.1139}, abstractNote={Four commercial table egg genetic stocks consisting of the Ottawa Control Strains 5, 7, and 10 (CS5, CS7, and CS10) and the 1993 H&N "Nick Chick" (CCS) were housed in the same environment and compared for production characteristics. These birds were housed in an environmentally controlled laying facility with trideck cages. Feed consumption, egg production, and mortality were monitored daily and compiled every 28 d. The study was conducted for two egg production cycles, including the molt period. Body weight was progressively lower for the more modern strains with CS5 being the heaviest and CCS maintaining the smallest body weight throughout the production periods. The CCS had the highest (P < 0.0001) hen-day production rate, which resulted in the greatest daily egg mass among the strains. The CCS consumed the greatest amount of feed and exhibited the highest gross egg income among the strains. We concluded that genetic selection has improved production parameters in commercial layers as determined by measurements in this study.}, number={8}, journal={POULTRY SCIENCE}, author={Jones, DR and Anderson, KE and Davis, GS}, year={2001}, month={Aug}, pages={1139–1143} }
 @book{jones_curtis_tharrington_jones_2000, place={Wallingford, UK}, title={Effects of Cryogenic Cooling of Shell Eggs on Interior Quality and Microbiological Integrity}, ISBN={9780851993300}, journal={Egg Nutrition and Biotechnology}, publisher={CABI Publishing}, author={Jones, D. R. and Curtis, P. A and Tharrington, J. B. and Jones, F. T.}, editor={Sim, J.S. and Nakai, S. and Guenter, W.Editors}, year={2000}, pages={411–416} }
 @article{keener_lacrosse_farkas_curtis_anderson_2000, title={Gas exchange into shell eggs from cryogenic cooling}, volume={79}, ISSN={["0032-5791"]}, DOI={10.1093/ps/79.2.275}, abstractNote={The gas composition of the air cell in a shell egg is influenced by heating from egg washing and candling and the method of cooling and storage. This study found that N2 gas (-122 C), CO2 gas (-45 C), and cold air (-15 C) could be used to rapidly cool shell eggs from 47.7 C to 7 C in 30 min or less. These results suggest that the gas composition of the air cell in shell eggs can be significantly modified using N2 cooling and CO2 cooling. Commercial field studies have shown that these modifications, which take place during cryogenic cooling, can significantly reduce microbial levels and increase shelf life of shell eggs. Storage in a modified atmosphere environment further enhanced these changes. It was found that the CO2 concentration in the air cell of a shell egg can be increased from 0.04 to 48% by CO2 cooling and storage in a CO2 environment.}, number={2}, journal={POULTRY SCIENCE}, author={Keener, KM and Lacrosse, JD and Farkas, BE and Curtis, PA and Anderson, KE}, year={2000}, month={Feb}, pages={275–280} }
 @article{davis_anderson_carroll_2000, title={The effects of long-term caging and molt of Single Comb White Leghorn hens on herterophil to lymphocyte ratios, corticosterone and thyroid hormones}, volume={79}, ISSN={["1525-3171"]}, DOI={10.1093/ps/79.4.514}, abstractNote={Two commercial strains of 18-wk-old Single Comb White Leghorn (SCWL) hens, HyLine W-36 and DeKalb XL, were housed six hens per cage in layer cages at two densities (361 and 482 cm2 per bird) with two replications each per strain and density combination. The high density treatment contained 24 hens per replication, and the low density treatment contained 18 hens per replication. Egg production was measured during the first egg production cycle, a molt (fast) period, and the first 4 wk of the second lay cycle (20 to 68 wk of age). Blood samples were obtained from six hens from each replicate in each strain and density combination (total of 48) at 20, 26, 34, 43, 51, 62, 64, and 68 wk of age. In addition, blood samples were obtained in a random order from hens in each cage, and the sequence of sampling was recorded (1 to 6). Blood smears were made, from which heterophil to lymphocyte ratios (H:L) were determined. Radioimmunoassays were conducted to determine levels of plasma corticosterone (CS), 3,5,3'-triiodothyronine (T3), and thyroxine (T4). The results indicated that strain did not affect percentage hen-day egg production (%HDP). Strain and cage density did not affect H:L, T3, T4, or CS. However, these parameters were affected by bird age, which was related to the egg production cycle. Plasma CS significantly (P < or = 0.001) increased during peak %HDP at 26 wk and 64 wk during the molt (fast), and H:L significantly (P < or = 0.001) increased during the molt (fast) at 64 wk. The sequence in which blood samples were obtained, from hens within a cage in sampling order, also increased plasma CS. The CS was significantly (P < or = 0.001) elevated in the third, fifth, and sixth hens from which blood samples were drawn. Plasma T3 and T4 changed during the production cycle. The T3 was significantly (P < or = 0.0001) depressed during peak egg production at 26 wk and during the molt (fast) at 64 wk when compared with the other time periods. Plasma T4 was depressed (P < or = 0.0001) at 51 wk and was elevated (P < or = 0.0001) at 64 wk during the molt (fast). The physiological and metabolic parameters of the different hen strains and cage densities were similar during egg production. However, CS, T3, T4, and H:L changed with age in relation to the egg production cycle. In addition, the physiological demands of peak egg production and molt (fast) appeared to be similar.}, number={4}, journal={POULTRY SCIENCE}, author={Davis, GS and Anderson, KE and Carroll, AS}, year={2000}, month={Apr}, pages={514–518} }
 @article{keener_lacrosse_curtis_anderson_farkas_2000, title={The influence of rapid air cooling and carbon dioxide cooling and subsequent storage in air and carbon dioxide on shell egg quality}, volume={79}, ISSN={["0032-5791"]}, DOI={10.1093/ps/79.7.1067}, abstractNote={This study examined the effect of rapid cooling with air and CO2 on shell egg quality over 14 wk. The 240 fresh eggs were initially heated to 47 C for 24 h in an incubator, cooled using rapid air cooling or CO2 cooling, and then stored in air or CO2 in 250-mL jars for 14 wk. The CO2 levels were recorded of the jar atmosphere, of the egg air cell, and of the egg albumen. The Haugh units of each egg, pH, and of albumen from five eggs per group were also recorded. Haugh units are a logarithmic, empirical relationship between albumen height and egg weight (Stadelman, 1995). Haugh units for the control eggs averaged 70.8 over 10 wk of the study. The control eggs were of such poor quality that they could not be sampled after 10 wk. The air-cooled and CO2-stored eggs averaged 70.3 Haugh units over the 14-wk storage period; however, the egg quality significantly deteriorated after 10 wk. The CO2-cooled and CO2-stored eggs averaged 75.9 Haugh units over the 14 wk study, with no observable decrease in quality. Rapid air-cooling produces a lower quality egg than rapid cooling with CO2. Subsequent storage of rapidly air-cooled eggs in C02 may increase shelf life, but Haugh units were not statistically different from rapid air-cooled eggs. CO2-cooling and subsequent storage in CO2 increased Haugh units. The shelf life of shell eggs could be extended to greater than 14 wk when the eggs were CO2-cooled and CO2-stored.}, number={7}, journal={POULTRY SCIENCE}, author={Keener, KM and LaCrosse, JD and Curtis, PA and Anderson, KE and Farkas, BE}, year={2000}, month={Jul}, pages={1067–1071} }
 @article{tharrington_curtis_jones_anderson_1999, title={Comparison of physical quality and composition of eggs from historic strains of single comb white leghorn chickens}, volume={78}, DOI={10.1093/ps/78.4.591}, abstractNote={The effect of long-term genetic selection on physical quality and composition of eggs was determined by analyzing eggs acquired from Agriculture Canada: Ottawa Control Strain 5 (CS5) from a 1950 base population, 7 (CS7) from a 1958 population and 10 (CS10) from a 1972 population. Eggs from the H&N "Nick Chick" current commercial strain (CCS) were also included. Eggs were collected monthly over a 62-wk laying period and analyzed for egg, albumen, shell and yolk weight; albumen protein, solids and pH; percentage yolk solids and fat; Haugh units; and specific gravity. Significant (P < 0.05) differences found between strains included a progressive increase in weight of eggs from the CS5 to CCS. Although the eggs increased in size, no significant differences were found between strains for specific gravity or percentage shell weight. Yolk weights of eggs from the strains examined did not differ. However, the percentage of yolk found in current strain eggs was significantly lower (P < 0.05), with a subsequent higher percentage albumen due to the increase in egg size of the CCS. Haugh units were significantly higher in the CS10 and CCS strains than in the other strains. No significant differences between strains were seen in albumen protein, solids, pH, or yolk solids. Mean percentage yolk fat assay values for eggs from the CS5, CS7, CS10, and CCS strains were 33.08, 32.68, 32.84, and 32.40, respectively. Percentage yolk fat values obtained from CCS were significantly lower (P < 0.05) than those obtained from the other strains. The results from this study indicate that genetic selection has produced larger eggs containing a lower percentage of yolk while overall egg quality has been maintained or improved.}, number={4}, journal={Poultry Science}, author={Tharrington, J. B. and Curtis, P. A. and Jones, F. T. and Anderson, Kenneth}, year={1999}, pages={591–594} }
 @article{carter_anderson_arends_barker_burton_hawkins_parsons_rives_scheidler_stringham_et al._1998, title={Composting Poultry Mortality}, volume={3}, journal={Problems of Ecological Security in Agriculture}, author={Carter, T.A. and Anderson, K. and Arends, J. and Barker, J. and Burton, S. and Hawkins, B. and Parsons, J. and Rives, D. and Scheidler, S. and Stringham, S. and et al.}, year={1998}, pages={95–105} }
 @inbook{zeidler_anderson_samimi_stadelman_yang_1998, place={Atlanta, GA}, edition={I-P and S-I Editions}, title={Eggs and Egg Products}, ISBN={9781883413538}, booktitle={1998 ASHRAE Handbook: Refrigeration}, publisher={American Society of Heating, Refrigeration, and Air-Conditioning Engineers, Inc}, author={Zeidler, G. and Anderson, K.E. and Samimi, M. and Stadelman, W.J. and Yang, T.}, year={1998} }
 @article{lucore_jones_anderson_curtis_1997, title={Internal and external bacterial counts from shells of eggs washed in a commercial-type processor at various wash-water temperatures}, volume={60}, ISSN={["0362-028X"]}, DOI={10.4315/0362-028X-60.11.1324}, abstractNote={The effects of two egg holding temperatures (15.5 and 26.7°C) and three wash-water temperatures (15.5, 32.2, and 48.9°C) on internal and external shell surface bacterial counts were tested by using a commercial-type egg-processing unit. Two experiments consisting of five trials, each of which included 360 eggs per treatment for a total of 2,160 per trial, were conducted during two seasons (summer and winter) for a total of 10 replicates per experiment. During the performance of each replicate, counts from tryptic soy agar (TSA) and MacConkey agar (MAC) were obtained from 10 egg samples which were collected prior to processing (prewash), immediately after washing (postwash), and after as-day cooling period at 7.2°C (postcool). No growth was observed on MAC plates in either experiment, indicating that fewer than 100 counts were detected. No significant differences (P > 0.05) were observed in the prewash, postwash, or postcool internal shell counts of eggs held at l5.5°C compared to internal counts of shells of eggs held at 26.7°C. Likewise, no significant differences (P > 0.05) were observed in the prewash, postwash, or postcool internal shell counts obtained from eggs washed in l5.5°C water compared with internal shell counts obtained from eggs washed in water at 32.2 or 48.9°C. On the basis of our data, spray washing eggs in l5.5°C water does not appear to increase internal shell bacterial counts. Because warm or hot wash water increases egg temperatures markedly, a reexamination of cold-water processing procedures may be in order.}, number={11}, journal={JOURNAL OF FOOD PROTECTION}, author={Lucore, LA and Jones, FT and Anderson, KE and Curtis, PA}, year={1997}, month={Nov}, pages={1324–1328} }
 @article{curtis_anderson_jones_1997, title={Plan de HACCP para plantas de clasificacion de huevos}, volume={44}, number={10}, journal={Industria Avicola}, author={Curtis, P.A. and Anderson, K.E. and Jones, F.T.}, year={1997}, pages={10–12} }
 @article{edens_anderson_havenstein_brake_anderson_1995, title={Concentrations of corticosterone and luteinizing hormone in plasma during the ovulatory cycle of laying hens}, volume={14}, number={8}, journal={International Journal of Poultry Science}, author={Edens, F.W. and Anderson, K.E. and Havenstein, G.B. and Brake, J. and Anderson, K.E.}, year={1995}, pages={1079–1092} }
 @article{curtis_anderson_jones_1995, title={Cryogenic Gas for Rapid Cooling of Commercially Processed Shell Eggs Before Packaging}, volume={58}, ISSN={0362-028X 1944-9097}, url={http://dx.doi.org/10.4315/0362-028x-58.4.389}, DOI={10.4315/0362-028x-58.4.389}, abstractNote={Research was initiated to evaluate the effects on egg quality and microbial counts of rapidly cooling eggs by using cryogenic gases. Four trials were conducted utilizing a 2 × 2 factorial design with cryogenic cooling and Pseudomonas inoculation as the main variables. The 1440 eggs used in each trial were evaluated for cracked shells, Haugh units, and albumen pH. Cryogenically cooled treatment groups were successfully cooled from 37°C to 7°C in significantly less time than in a traditionally cooled pallet. The Haugh unit values obtained from traditionally cooled eggs were significantly (P > .001) lower than those from cryogenically cooled eggs. There was no significant difference in the albumen pH of the two groups. Internal and external bacterial counts revealed significantly fewer bacteria in the interior of cryogenically cooled eggs than in the interior of traditionally cooled eggs. However, after a 30-day storage period at 7°C, no difference was found in external and internal bacterial contamination rates. The results of this trial suggest that rapid cooling with cryogenic gases could be used in conjunction with current commercial egg processing to cool eggs prior to packaging. The successful commercial application of this procedure would reduce egg temperatures as well as the likelihood of Salmonella enteritidis growth in or on eggs. Thus, consumers would be provided with safer commercially processed shell eggs. In addition, the Haugh unit data indicate that rapid cooling with cryogenic gases enhances the quality of commercially processed shell eggs.}, number={4}, journal={Journal of Food Protection}, publisher={International Association for Food Protection}, author={Curtis, Patricia A. and Anderson, Kenneth E. and Jones, Frank T.}, year={1995}, month={Apr}, pages={389–394} }
 @article{jones_anderson_ferket_1995, title={Effect of Extrusion on Feed Characteristics and Broiler Chicken Performance}, volume={4}, ISSN={1056-6171}, url={http://dx.doi.org/10.1093/japr/4.3.300}, DOI={10.1093/japr/4.3.300}, abstractNote={Abstract Broiler feeds of identical formulas were fed to straight run broilers in the form of either non-heat treated mash, pellets, or extruded pellets to test the effect of feed processing on production parameters. Young broilers at ≤ 2wk old which were fed crumbled starter rations extruded prior to crumbling weighed more than birds fed crumbled starter rations that were pelleted prior to crumbling. However, when broilers received rations not crumbled following processing, birds fed extruded diets weighed less than those fed pelleted diets. Extruded feeds weighed less per unit volume than pelleted feeds. This density difference may account for the differences in body weights observed. The traditional ether extraction procedure detected a smaller percentage of the fat present in extruded feeds than did acid hydrolysis procedures. In addition, the extrusion process caused some protein and amino acid destruction. Therefore, extruded rations should be formulated at slightly higher nutrient density to compensate for nutrient destruction and loss of nutrient digestibility.}, number={3}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Jones, F.T. and Anderson, K.E. and Ferket, P.R.}, year={1995}, month={Oct}, pages={300–309} }
 @article{carey_kuo_anderson_1995, title={Effects of Cage Population on the Productive Performance of Layers}, volume={74}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0740633}, DOI={10.3382/ps.0740633}, abstractNote={Two commercial layer strains (3,456 hens total) were used to examine the effects of bird population on productive performance. Four cage population sizes (6, 8, 12, and 24 birds per cage) were compared. All cages were 35.7 cm deep and varied in width (61.2, 81.6, 122.4, and 244.8 cm). Floor space per bird was 364.1 cm2 and feeder space per bird was 10.2 cm in each cage configuration. Egg production and egg quality were measured from 20 to 72 wk of age. Strain differences were detected in hen-day egg production, egg mass, feed consumption, cracked egg percentage, Grade A eggs, Grade B eggs, peewee eggs, and large egg yield. There were no interactions between strain and cage population size. Cage population had no influence on hen-day egg production, mortality, feed conversion, egg size (peewee, small, medium, large, extra large), egg mass, lost eggs (by meat or blood spots), and percentage Grade B eggs. Percentage Grade A eggs, cracked egg percentage, and feed consumption were significantly influenced by cage population size. Hens housed at eight birds per cage had a greater percentage of Grade A eggs and a lower percentage of cracked eggs than those at other populations. Feed consumption was significantly greater for hens housed at 12 and 24 birds per cage compared with those at 6 and 8 birds per cage, respectively.}, number={4}, journal={Poultry Science}, publisher={Elsevier BV}, author={Carey, J.B. and Kuo, F.L. and Anderson, K.E.}, year={1995}, month={Apr}, pages={633–637} }
 @article{anderson_havenstein_brake_1995, title={Effects of strain and rearing dietary regimens on brown-egg pullet growth and strain, rearing dietary regimens, density, and feeder space effects on subsequent laying performance}, volume={74}, ISSN={["0032-5791"]}, DOI={10.3382/ps.0741079}, abstractNote={The objective of this experiment was to compare the growth and development of two brown-egg strains when grown on three different dietary regimens, i.e., a "normal" step-down protein (SDP) regimen, a step-up protein regimen with a low energy starter (SUPLES), and a step-up protein regimen with a high energy starter (SUPHES). The SUPLES and SUPHES feeding regimens resulted in significantly lower BW and feed conversion, shorter sternum length, and lower tibial breaking strength than the SDP regimen. The weights of the liver, spleen, and fat pad were not different among the three regimens. The high energy starter in the SUPHES regimen significantly reduced FC below that obtained with the SUPLES program. The SUPHES regimen significantly reduced total feed cost compared with the other two feeding regimens. Both step-up protein regimens reduced total protein, energy, Ca, P, lysine, and sulfur amino acid consumption. Because tibial breaking strength was also reduced by the step-up protein regimens, the data suggest that the levels of dietary Ca and P should be increased with these programs to compensate for the reduced consumption associated with them.}, number={7}, journal={Poultry Science}, author={Anderson, K.E. and Havenstein, G.B. and Brake, J.}, year={1995}, pages={1079–1092} }
 @misc{anderson_curtis_jones_1995, title={Rapid chilling of shell eggs using cryogenic gases}, volume={5474794}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Anderson, K. E. and Curtis, P. A. and Jones, F. T.}, year={1995} }
 @article{al batshan_scheideler_black_garlich_anderson_1994, title={Duodenal Calcium Uptake, Femur Ash, and Eggshell Quality Decline with Age and Increase Following Molt}, volume={73}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0731590}, DOI={10.3382/ps.0731590}, abstractNote={An experiment was conducted to test the hypothesis that the decline in eggshell quality over time during egg production, and its improvement after molting, paralleled the rate of calcium uptake by the duodenum of the laying hen. In vitro duodenal calcium uptake rate and femur ash (percentage of femur weight) were determined at 37, 45, 51, 58, 68, and 72 wk of age. Percentage shell and shell thickness (millimeters) were determined at 22, 29, 36, 44, 50, 57, and 71 wk of age. Molt was induced at 63 wk of age. Three commercial strains DeKalb XL-Link, ISA/Babcock B-300V, and Hy-Line W-36 were compared. There were no differences in duodenal calcium uptake rate among strains. There was a significant decline (P < .01) in duodenal calcium uptake from 408 pmol/mg tissue per min at 37 wk of age to 329 pmol/mg per min at 58 wk of age. Femur ash decreased (P < .01) from 50.8% at 37 wk of age to 47.6% at 58 wk of age. Percentage shell and shell thickness declined (P < .01) from 9.79% and .403 mm at 22 wk of age to 8.88% and .373 mm at 57 wk of age, respectively. After the induced molt, duodenal calcium uptake increased (P < .01) to 402 pmol/mg tissue per min, and percentage shell and shell thickness increased (P < .01) to 10.23% and .389 mm, respectively. Duodenal calcium uptake increased immediately postmolt, whereas femur ash did not increase until 72 wk of age (P < .01).}, number={10}, journal={Poultry Science}, publisher={Elsevier BV}, author={Al Batshan, H.A. and Scheideler, S.E. and Black, B.L. and Garlich, J.D. and Anderson, K.E.}, year={1994}, month={Oct}, pages={1590–1596} }
 @article{anderson_adams_1994, title={Effects of Cage Versus Floor Rearing Environments and Cage Floor Mesh Size on Bone Strength, Fearfulness, and Production of Single Comb White Leghorn Hens ,}, volume={73}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0731233}, DOI={10.3382/ps.0731233}, abstractNote={Fourteen hundred pullets were reared at densities of 304 and 735 cm2 in cages and floor pens with litter, respectively. Feeder spaces of 2.7, 4.0, and 5.4 cm per bird were held constant during the brooding growing period. At 18 wk of age, the birds were housed four birds per cage (348 cm2 per bird) in a force-ventilated, light-controlled house with two rows of stair-step cages. In two rows, the standard 2.5 x 5.0 cm welded wire flooring was replaced randomly with 2.5 x 2.5 cm welded wire in eight-cage sections. Egg production, egg quality, feed conversion, and mortality were measured over a 48-wk production cycle. At 68 wk of age, a sample of hens was selected and euthanatized, and the right leg was excised for further evaluation. Rearing environment, rearing feeder space, or type of layer floor mesh had no significant effects on hen-day production or feed conversion. Hens reared in cages produced heavier (P < .001) eggs with a higher percentage of Grade A eggs and had fewer body checks than floor-reared birds. Femur, tibia, and shank lengths were not affected by the rearing treatments or the type of flooring in the layer cage. Tibia breaking strength was not different for the rearing systems or hens maintained on 2.5 x 2.5 vs 2.5 x 5.0 cm welded wire mesh flooring. Hens reared in floor pens on litter displayed a higher level of fearfulness at the end of the production cycle. The reduced (P < .05) body weights associated with cage rearing and reduced feeder space did not negatively affect the production variables. Alteration of the mesh size of layer cage floor had no effect on the production levels of the hens.}, number={8}, journal={Poultry Science}, publisher={Elsevier BV}, author={Anderson, K.E. and Adams, A.W.}, year={1994}, month={Aug}, pages={1233–1240} }
 @article{anderson_adams_1994, title={Effects of floor versus cage rearing and feeder space on growth, long bone development, and duration of tonic immobility in single comb White Leghorn pullets}, volume={73}, DOI={10.3382/ps.0730958}, abstractNote={The effects of feeder space on growth of commercial layer pullets reared in cages or floor pens were examined by allocating 1-d-old chicks to either cages (14 chicks) or floor (119 chicks). Feeder spaces were 5.4, 4.0, and 2.7 cm per pullet and were held constant throughout the growing period, resulting in a 2 x 3 factorial arrangement. Measurements of pullet body weight, feed consumption, skeletal development, and fearfulness were taken through the rearing period to 18 wk. Pullets allowed 5.4 cm of feeder space were heavier (P < .001) (1,329 g at 18 wk of age) than birds allowed either 4.0 or 2.7 cm of feeder space (1,289 and 1,272 g, respectively). Floor-reared pullets weighed significantly more at 12, 16, and 18 wk of age than cage-reared pullets. Feed consumption was not affected by the feeder space, but the floor-reared birds consumed more (P < .001) feed than those in cages (61.2 vs 52.8 g per pullet per d). Mortality, skeletal development, and bone strength were not affected by either feeder space or floor vs cage rearing. Floor-reared pullets had longer (P < .05) duration of tonic immobility (TI) than those reared in cages (519.7 and 471.4 s, respectively, as measured at 18 wk). Feeder space per pullet had no effect on the duration of TI of the pullets. Cage and floor rearing environments are comparable for rearing pullets provided feeder space is not restricted to such an extent as to inhibit BW.}, number={7}, journal={Poultry Science}, author={Anderson, Kenneth and Adams, A. W.}, year={1994}, pages={958} }
 @article{davis_anderson_parkhurst_rives_hagler_1994, title={Mycotoxins and Feed Refusal by Pekin Ducks}, volume={3}, ISSN={1056-6171}, url={http://dx.doi.org/10.1093/japr/3.2.190}, DOI={10.1093/japr/3.2.190}, abstractNote={Abstract High mortality occurred in two flocks of ducklings: 20% and 50% by 4 and 7 days of age, respectively. The feeds were found to contain 300 to 1176 ppb of deoxynivalenol (DON), 4.5 ppm of fumonisin, and 10 ppb of aflatoxin B1. No other mycotoxins were detected. Pathological analysis indicated that the ducklings were dehydrated with no feed in the gastrointestinal tract. Histopathology revealed no significant lesions. A necropsy diagnosis indicated a condition similar to starve-outs and feed refusal. An infectious cause of mortality was not suspected.}, number={2}, journal={Journal of Applied Poultry Research}, publisher={Elsevier BV}, author={Davis, G.S. and Anderson, K.E. and Parkhurst, C.R. and Rives, D.V. and Hagler, W.M.}, year={1994}, month={Jul}, pages={190–192} }
 @article{anderson_adams_1992, title={Effects of Rearing Density and Feeder and Waterer Spaces on the Productivity and Fearful Behavior of Layers}, volume={71}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0710053}, DOI={10.3382/ps.0710053}, abstractNote={Abstract Two groups of White Leghorn pullets reared in cages were used to study the effects of rearing density and feeder and waterer spaces on their performance and fearful behavior. In Experiment 1, rearing densities of 221, 249, 277, and 304 cm2 per bird, 5.4 cm feeder space per bird, and a cup waterer to pullet ratio of 1:7 had no significant effect on 18-wk body weight, body weight uniformity, body weight gain, age at sexual maturity, feed consumption, and mortality rate during the laying period. In Experiment 2, pullets reared at a density of 193 versus 221 cm2 had lower (P}, number={1}, journal={Poultry Science}, publisher={Elsevier BV}, author={Anderson, K.E. and Adams, A.W.}, year={1992}, month={Jan}, pages={53–58} }
 @article{anderson_adams_1991, title={Effects of Type of Cage Front and Feed Trough Partitions on Productivity and Ingestive, Agonistic, and Fearful Behaviors of Egg-Type Hens}, volume={70}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0700770}, DOI={10.3382/ps.0700770}, abstractNote={Two groups of White Leghorn pullets reared in floor pens were used to study the effects on performance and behavior in cages of horizontal wire cage fronts with and without feed trough partitions (HP and H, respectively) and vertical wire cage fronts with and without feed trough partitions (VP and V, respectively). In Experiment 1, hens in HP and VP cages consumed more (P less than .05) feed than hens in either H or V cages. This greater feed consumption combined with similar egg production resulted in significantly poorer feed conversion (P less than .05) for hens in VP cages. Hens in HP cages had fewer drinking bouts (P less than .05) and an intermediate amount of feeding time. Hens in H, V, and VP cages did not differ significantly in number of drinking bouts and feeding times. There were differences in feeding location preferences among treatments (P less than .05) but not within treatments. In Experiment 2, effects of horizontal (H) and vertical (V) wire cage fronts were examined to determine their effects on productivity and fearful behavior. Hens in H cages had better feather scores (P less than .05) than hens in V cages. Type of cage front had no significant effects on age at sexual maturity, egg production, mortality rate, average egg weight, and body weight.}, number={4}, journal={Poultry Science}, publisher={Elsevier BV}, author={Anderson, K.E. and Adams, A.W.}, year={1991}, month={Apr}, pages={770–775} }
 @article{anderson_adams_craig_1989, title={Behavioral Adaptation of Floor-Reared White Leghorn Pullets to Different Cage Densities and Cage Shapes During the Initial Settling-in Period}, volume={68}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0680070}, DOI={10.3382/ps.0680070}, abstractNote={Abstract Two groups of White Leghorn pullets, reared in floor pens, were observed for changes in behavioral traits when housed in cages. Data in Experiment 1 were obtained during Days 1 to 5 posthousing from 40 pullets kept in eight 40.7-cm wide × 45.7-cm deep cages with either four or six birds/cage and in Experiment 2 during Days 1 to 5 and Day 7 posthousing from 24 pullets housed four/cage in three 30.5-cm wide × 45.7-cm deep cages (deep cages), and three 45.7-cm wide × 30.5-cm deep cages (shallow cages). In Experiment 1, pullets housed four/cage spent significantly (P}, number={1}, journal={Poultry Science}, publisher={Elsevier BV}, author={Anderson, K.E. and Adams, A.W. and Craig, J.V.}, year={1989}, month={Jan}, pages={70–78} }
 @article{anderson_adams_1988, title={Research Note: Effects of Feed Trough Partitions on Productivity and Behavior of Layers}, volume={67}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0671348}, DOI={10.3382/ps.0671348}, abstractNote={Abstract Pullets reared to 18 wk of age in floor pens were placed in 30.5 wide × 45.7-cm deep (deep) or 45.7 wide × 30.5-cm deep (shallow) layer cages with 348 cm2 floor area/bird. The feed trough was divided into four equal compartments by partitions constructed of 1.2-cm hardware cloth and extending from the bottom of the trough to the top of the cage. This allowed the hens to feed but not interfere with one another while at the feeder. Observations were made on the effects of cage shape and feed trough partitions on the productivity and behavior of the hens. Cage shape significantly (P}, number={9}, journal={Poultry Science}, publisher={Elsevier BV}, author={Anderson, K.E. and Adams, A.W.}, year={1988}, month={Sep}, pages={1348–1351} }
 @article{ramos_anderson_adams_1986, title={Effects of Type of Cage Partition, Cage Shape, and Bird Density on Productivity and Well-Being of Layers}, volume={65}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0652023}, DOI={10.3382/ps.0652023}, abstractNote={In Experiment 1 there were no significant differences in rate of lay, egg quality, latency to feeding, and feather condition of hens in cages with wire mesh or solid metal side partitions. Birds in cages with solid metal side partitions had significantly higher mortality (6%) and weight gain (6%) than those in cages with wire side partitions. The deep caged hens had significantly lower mortality (8%) than the shallow caged hens. Hens housed at 464 cm2 of floor area/hen had significantly higher hen-housed egg production (4.9%), lower weight gain (8%), and higher average feather scores (.8 unit) than those housed at 348 cm2. In Experiment 2 type of cage side and back partitions (wire vs. solid metal) significantly affected grams of egg per gram of feed. Birds in deep cages had significantly lower mortality (8.6%) and higher feed consumption (15.2 g/hen/day) than those in shallow cages. Hen-housed rate of lay, mortality, weight gain, feed conversion, and feather scores were significantly affected by bird density: 64.6%, 15%, 24.6%, .384% g egg/g feed, and 4.7 units, respectively, for hens with 464 cm2 floor area vs. 70.8%, 8.3%, 25.2%, .362% g egg/g feed, and 5.8 units for hens with 348 cm2. Data suggest that hens in cages with solid metal sides performed similarly to their sisters in cages with wire mesh sides and backs.}, number={11}, journal={Poultry Science}, publisher={Elsevier BV}, author={Ramos, N.C. and Anderson, K.E. and Adams, A.W.}, year={1986}, month={Nov}, pages={2023–2028} }