@article{lowman_parkhurst_2014, title={The effect of feeding Hydrogel-95 to emu chicks at hatch}, volume={23}, ISSN={["1537-0437"]}, DOI={10.3382/japr.2013-00835}, abstractNote={Abstract Very little research has been conducted on emu (Dromaius novaehollandiae) in comparison to other types of poultry. Much of the information that is available to producers is very conflicting. Feed restriction for the emu chick for the first 4 d of life is a common practice among the emu industry; however, scientific research has not supported this practice. To the best of our knowledge, the effects of hydration supplements have not been investigated in the emu. Therefore, weights were recorded on emus fed Hydrogel-95 and were compared with emus that were not fed any supplements to determine if the supplement had any effect on the growth parameters of emu chicks. From these 2 field trials, we conclude that feeding Hydrogel-95 significantly decreases weight loss in emu chicks during the first week of life.}, number={1}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Lowman, Zachary and Parkhurst, Carmen}, year={2014}, month={Mar}, pages={129–131} }
 @article{lowman_parkhurst_2014, title={The length of storage of emu eggs and resultant effects on hatchability}, volume={23}, ISSN={["1537-0437"]}, DOI={10.3382/japr.2014-01004}, abstractNote={SUMMARY Emu (Dromaius novaehollandiae) are a large flightless bird and are members of the Ratite family. Emu originated from Australia and have long been raised for their meat and oil. The cost associated with raising emu is high, which makes emu meat and products expensive. Emu have very low hatchability rates when compared with other commercial poultry. To date, little research has been published on egg storage conditions of emu eggs, which may contribute to the decreased hatchability of the eggs. In this study, eggs were stored for times ranging from 1 to 8 wk and subsequent effects on moisture loss and hatchability was recorded. we found significant differences (P < 0.0104) in hatchability of emu eggs due to storage time. Significant differences (P < 0.0001) were also found in moisture loss due to egg storage. Based on these data, 2 wk of egg storage appears to be the optimal storage time. After 3 wk of storage, hatchability begins to decrease.}, number={4}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Lowman, Zachary and Parkhurst, Carmen}, year={2014}, month={Dec}, pages={759–762} }
 @article{edens_parkhurst_ferket_havenstein_sefton_2002, title={A demonstration of postpellet application of dry phytase to broiler diets}, volume={11}, ISSN={["1056-6171"]}, DOI={10.1093/japr/11.1.34}, abstractNote={SUMMARY A comparison of performance and P reduction in litter and manure from broilers fed rations with and without phytase enzyme was made with chickens reared on litter or in cages. Low-activity phytase supplemented as a dry powder to mash diets did not affect performance, but litter P accumulation was decreased 14 to 21% in the finisher phase. Manure P content of broilers in cages was reduced 14 to 19% during the starter and grower phases. Liquid phytase applied postpelleting to diets with 0.5% total P (0.3% available P) reduced litter P accumulation (14 to 19%) and reduced manure P content in starter, grower, and finisher phases of the study. Phosphorus content in raw manure was decreased by 55% during the finisher phase. Feed conversions of broilers in cages and on conventional litter-covered floors were improved significantly with postpellet application of liquid phytase. Feed conversion improvement was greater in birds in cages. Postpellet application of dry phytase was shown to be feasible based upon performance and reduction in litter P accumulation. Feed conversions were improved by 7 to 8 points (P < 0.05) when compared to those of birds given a normal P level (0.72% total P) diet without phytase. Litter P accumulation was reduced between 20.5 and 28.5% with dry phytase applied postpelleting. With liquid phytase applied postpelleting, litter P accumulation was reduced 26.6%. These reductions in litter P content represent about 4 lb of P per ton of litter.}, number={1}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Edens, FW and Parkhurst, CR and Ferket, PR and Havenstein, GB and Sefton, AE}, year={2002}, pages={34–45} }
 @article{roy_edens_parkhurst_qureshi_havenstein_2002, title={Influence of a propionic acid feed additive on performance of turkey poults with experimentally induced poult enteritis and mortality syndrome}, volume={81}, ISSN={["1525-3171"]}, DOI={10.1093/ps/81.7.951}, abstractNote={
 Abstract
 
 Poult enteritis and mortality syndrome (PEMS) has multiple etiological agents associated with its occurrence, including two viruses and at least three Escherichia coli isolates. Myco Curb (MC) contains organic acids and is used as a feed additive to inhibit growth of many bacteria and toxin-producing molds but not viruses. Studies evaluating the influence of MC on BW, feed conversion, and mortality indicate that turkey poults tolerate MC at 1.25% but not 2.50%, but higher MC content in feed provides greater suppression of growth of bacterial isolates commonly associated with PEMS. In two PEMS experiments, 1.25% MC was blended into poult starter feed and was maintained in the feed for the duration of the 3-wk experiments. In these experiments, 1-d-old commercial poults were placed into battery brooders and were given turkey starter feed and water ad libitum. At 6 d posthatch, PEMS-designated poults were given a 1-mL oral gavage of a 10% suspension of feces from PEMS-infected poults. BW depression due to PEMS was not alleviated by MC, although there was less variation in mean BW of the MC-fed poults, and there was a highly significant reduction in mortality (68% in PEMS-exposed with MC vs. 32.5% in PEMS-exposed without MC). The reduction in mortality in the MC-fed poults was attributed to decreased bacterial content of the gut and to maintenance of packed cell volume and hemoglobin content. It was concluded that MC might be a potential nutritional intervention during PEMS.
 
}, number={7}, journal={POULTRY SCIENCE}, author={Roy, RD and Edens, FW and Parkhurst, CR and Qureshi, MA and Havenstein, GB}, year={2002}, month={Jul}, pages={951–957} }
 @article{edens_parkhurst_havenstein_sefton_2001, title={Housing and selenium influences on feathering in broilers}, volume={10}, ISSN={["1056-6171"]}, DOI={10.1093/japr/10.2.128}, abstractNote={SUMMARY A majority of the broilers produced around the world are sexed on the basis of rapid-feathering females or slow-feathering males, which is facilitated by the presence of the sex-linked, auto-sexing, slow-feathering K gene in males. Recent advances in materials have allowed development of a caging system that is a viable alternative to the traditional floor-rearing regimen. In this study, a comparison was made between the traditional floor- and cage-rearing environments and their influence on feathering of auto-sexing, sex-linked male and female broilers fed at 0.2 mg/kg of feed either NaSe or an organic selenium yeast (OR). Feed conversion ratios, BW, and mortality were not affected by Se source. Feather tracts on the back, breast, thigh, wing, neck, and wing were scored subjectively based on feather size and skin surface covered. Feather scores ranged from 0 (no feathering) to 5 (best feathering) for each tract. The OR induced more rapid whole body feathering in the slow-feathering males as well as in the normal-feathering females. The influence of OR was evident from 21 through 42 d of age. Females had a faster feathering rate than did males. Females approached full feathering at 35 d of age, but males lagged behind females even at 42 d. Feathering of broilers in the conventional house was slightly faster than the feathering of broilers in the cage house. The mechanism for improved feathering rate in normal-feathering females and slow-feathering males given OR has not been determined.}, number={2}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Edens, FW and Parkhurst, CR and Havenstein, GB and Sefton, AE}, year={2001}, pages={128–134} }
 @article{doerfler_cain_edens_parkhurst_qureshi_havenstein_2000, title={D-xylose absorption as a measurement of malabsorption in poult enteritis and mortality syndrome}, volume={79}, ISSN={["0032-5791"]}, DOI={10.1093/ps/79.5.656}, abstractNote={
 Abstract
 
 Severe wasting of body tissues, diarrhea, high morbidity and mortality, and stunting are all characteristics of poult enteritis and mortality syndrome (PEMS). The wasting of musculature and loss of nearly all adipose tissue suggested that even though the PEMS-infected poults were eating some feed, nutrient intake was not sufficient to meet body requirements for maintenance and growth. Because epithelial cells in the gastrointestinal tract appeared to be a target of the undefined etiological agent (or agents) that causes PEMS, a study was conducted in which PEMS-infected poults were evaluated for malabsorption through 3 wk of age. D-Xylose, a poorly metabolized pentose, was given per os as a bolus, and blood samples were obtained from the ulnar vein in the wing of control and PEMS-infected poults over a 3-h period to estimate intestinal absorption. D-Xylose absorption in control poults peaked 30 to 60 min after the oral treatment, similar to results reported earlier. The PEMS-infected poults did not show a peak in absorption. The PEMS-infected poults showed significant delays in D-xylose absorption at 4, 7, and 11 d after PEMS challenge. The severe malabsorption and metabolic deficiency problem associated with PEMS was postulated to be a direct effect of the undefined infectious agent or agents that cause the disease.
 
}, number={5}, journal={POULTRY SCIENCE}, author={Doerfler, RE and Cain, LD and Edens, FW and Parkhurst, CR and Qureshi, MA and Havenstein, GB}, year={2000}, month={May}, pages={656–660} }
 @article{doerfler_edens_mcmurtry_qureshi_parkhurst_havenstein_2000, title={Influence of Biochrome (R) on the response of metabolic hormones in PEMS-infected poults}, volume={79}, ISSN={["1525-3171"]}, DOI={10.1093/ps/79.5.661}, abstractNote={
 Abstract
 
 Poult enteritis and mortality syndrome (PEMS), a disease that affects turkeys between 7 and 28 d of age, causes a severe inflammation of the intestinal tract and is characterized in poults by severe diarrhea, high morbidity, mortality, and stunting. The PEMS-associated mortality and growth depression is related to malabsorption and decreased metabolic activity caused, in part, by a possible insulin deficiency or insensitivity. Insulin receptors are stimulated by the glucose tolerance factor (GTF) that incorporates Cr. Body Cr deficiency can be exacerbated by dietary deficiency and by increased excretion due to stress associated with a diarrheal disease such as PEMS. BioChrome® (BC) contains natural, preformed GTF, the bioactive form of Cr. Experiments were conducted in which BC was blended into poult starter feed at 400 ppb during the first 21 d posthatch. Body weights were determined at 1, 7, 14, and 21 d of age, and weekly feed conversions were calculated for each treatment group (control, BC, PEMS, and BC+PEMS). At 6 d post-hatch, each PEMS-designated poult was given a 0.1-mL oral gavage of a 10% suspension of feces from PEMS-infected poults. Blood samples were taken via cardiac puncture from four birds per treatment group at 7, 10, 14, 17, and 21 d of age. Radioimmunoassays were conducted for plasma insulin, glucagon, thyroxine (T4), and triiodothyronine (T3). Plasma insulin levels were depressed in PEMS-infected poults from Days 10 through 17, but plasma glucagon levels in the PEMS-infected poults were significantly elevated at 14 and 17 d, after which they returned to control levels in both of the PEMS-infected groups. The T3 and T4 levels were depressed through Day 21 in PEMS-infected poults, but with BC treatment these blood hormone levels rebounded by Day 21. Body weights of PEMS-infected poults were increased significantly by the BC treatment but not to the level of noninfected controls.
 
}, number={5}, journal={POULTRY SCIENCE}, author={Doerfler, RE and Edens, FW and McMurtry, JP and Qureshi, MA and Parkhurst, CR and Havenstein, GB}, year={2000}, month={May}, pages={661–668} }
 @article{edens_joyce_parkhurst_havenstein_qureshi_1998, title={Effect of litter moisture and brooding temperature on body weights of turkey poults experiencing poult enteritis and mortality syndrome}, volume={77}, ISSN={["0032-5791"]}, DOI={10.1093/ps/77.3.411}, abstractNote={Studies were conducted to determine the influence of the interactions among litter moisture (high [HiM]> or =40% vs low [LoM]< or =20%), brooding temperature (high [HiB] = 38 C vs normal [NrB] = 34 C), and development of poult enteritis and mortality syndrome (PEMS) as indicated by body weights, relative weights of lymphoid organs, and mortality in Control [C] vs Infected [I] groups. There was a significant interaction between litter moisture and brooding temperature that had a significant influence on BW. The brooding temperature main effect was not significant, but there was a significant litter moisture effect on BW. Body weights were suppressed by PEMS infection, but infected poults brooded at HiB on LoM had significantly greater BW than those brooded at NrB and HiB on HiM. Main effects showed that there were significant litter moisture- and brooding temperature-mediated responses for BW. Relative weights of lymphoid organs revealed significant disease main effects but no effect due to brooding temperature and litter moisture. There was a significant effect of disease and brooding temperature with regard to mortality. The results from this study suggest that litter moisture influences productivity and mortality associated with PEMS, but brooding temperature has the greatest influence on PEMS-associated mortality. Therefore, higher brooding temperature for turkey poults being placed into a facility where they may be at risk for PEMS exposure is recommended.}, number={3}, journal={POULTRY SCIENCE}, author={Edens, FW and Joyce, KA and Parkhurst, CR and Havenstein, GB and Qureshi, MA}, year={1998}, month={Mar}, pages={411–415} }
 @article{doerfler_edens_parkhurst_havenstein_qureshi_1998, title={Hypothermia, hypoglycemia, and hypothyrosis associated with poult enteritis and mortality syndrome}, volume={77}, ISSN={["1525-3171"]}, DOI={10.1093/ps/77.8.1103}, abstractNote={
 Abstract
 
 A metabolic dysfunction contributes to the poor performance and mortality associated with Poult Enteritis and Mortality Syndrome (PEMS). Within 2 d after contact-exposed poults were removed from the presence of PEMS-infected poults and returned to their respective treatment rooms to infect experimental poults, the experimental poults began to huddle together and show signs of the disease. When separated from the huddle, body temperatures of exposure poults were depressed significantly. Body temperatures decreased progressively through 8 d after exposure with a maximum depression of 2 C and returned to a normal level at 18 d after PEMS exposure. Similar decreasing patterns in serum glucose, inorganic phosphorus, triiodothyronine, and thyroxine were observed, with maximum decreases in these serum constituents being found between 8 and 13 d after PEMS exposure. There were significant correlations among decreasing body temperatures, decreasing serum constituents, and mortality in the PEMS-exposed poults. Daily mortality rates associated with PEMS began at 6 d and peaked at 9 d after PEMS exposure. Mortality rates decreased from 9 to 15 d after experimental PEMS exposure. Depressions in serum constituents, body temperature, and increased mortality rates did not coincide with decreased feed intake associated with PEMS. Therefore, it was concluded that the agent(s) causing PEMS may have a direct effect on energy metabolism in afflicted poults.
 
}, number={8}, journal={POULTRY SCIENCE}, author={Doerfler, RE and Edens, FW and Parkhurst, CR and Havenstein, GB and Qureshi, MA}, year={1998}, month={Aug}, pages={1103–1109} }
 @article{edens_parkhurst_qureshi_casas_havenstein_1997, title={Atypical Escherichia coli strains and their association with poult enteritis and mortality syndrome}, volume={76}, ISSN={["0032-5791"]}, DOI={10.1093/ps/76.7.952}, abstractNote={
 Abstract
 
 To date, no definitive etiology has been described for Poult Enteritis and Mortality Syndrome (PEMS). However, two atypical Escherichia coli colony types are isolated consistently from moribund and dead poults afflicted with PEMS. To test the infectivity of these E. coli strains, poults were placed into floor pens in three isolation treatment rooms: 1) Control: no bacterial challenge, 2) E. coli colony Types 1 or 2 posthatch oral challenge: 10(8) cfu/per poult at 1 d, and 3) E. coli colony Types 1 or 2 posthatch oral challenge: 10(8) cfu/per poult at 6 d. Daily intramuscular injections of cyclophosphamide (100 micrograms per poult) from 1 to 5 d posthatch were given to half of the poults in each treatment. Atypical E. coli challenge caused BW depression, and cyclophosphamide treatment exacerbated the response. All E. coli-challenged poults developed diarrhea similar to PEMS. Mortality was increased by both atypical E. coli colony types, but at 21 d E. coli colony Type 2 caused greater mortality than colony Type 1. With cyclophosphamide treatment, mortality was exacerbated with both colony types, but colony Type 2 at 1 d caused the greatest mortality. Ultrastructural damage to ileum epithelium cell microvilli and subcellular organelles indicated that part of the BW depression could be attributed to malabsorption of nutrients. It was concluded that the atypical E. coli colony Types 1 and 2 play a significant role in the PEMS disease.
 
}, number={7}, journal={POULTRY SCIENCE}, author={Edens, FW and Parkhurst, CR and Qureshi, MA and Casas, IA and Havenstein, GB}, year={1997}, month={Jul}, pages={952–960} }
 @article{edens_qureshi_parkhurst_qureshi_havenstein_casas_1997, title={Characterization of two Escherichia coli isolates associated with poult enteritis and mortality syndrome}, volume={76}, ISSN={["0032-5791"]}, DOI={10.1093/ps/76.12.1665}, abstractNote={Two colonial types (1 and 2) of Escherichia coli are represented predominantly in cultures isolated from turkey poults with poult enteritis and mortality syndrome (PEMS). Biotype codes determined using two systems (BBL: 36570 and 34560 for colony types 1 and 2, respectively; API-20E: 5144572 and 5144512 for colony types 1 and 2, respectively) clearly establish these organisms as E. coli. These isolates were not clearly divergent from the general profile for E. coli, but colony type 2 differs from colony type 1 with regard to its negative reactions for ornithine decarboxylase and the fermentation of dulcitol, rhamnose, sucrose, and melibiose, suggesting that it is atypical. Colony type 1 is nonserotypable and nonmotile, whereas colony type 2 is serotyped as O136: motile because it has H antigens associated with flagella. Capsular antigens were not found, but thin capsules were seen on cells from both colony types in stained preparations. Cultural morphology was different with colony type 1 having a circular, mucoid, raised morphology and colony type 2 having an irregular, flat, rough morphology. Colony type 1 has a doubling time at 37 C of about 20 min, whereas colony type 2 doubles in 30 min. Furthermore, colony type 1 is a potent colicin producer, but colony type 2 is not a colicin producer. Both E. coli isolates have resistance profiles for multiple antibiotics. Each strain responds to third generation fluoroquinolone antibiotics by changing their biotypes and become resistant after culturing once in their presence. These E. coli are proposed as possible etiological links in the complex series of events that take place in poults susceptible to PEMS.}, number={12}, journal={POULTRY SCIENCE}, author={Edens, FW and Qureshi, RA and Parkhurst, CR and Qureshi, MA and Havenstein, GB and Casas, IA}, year={1997}, month={Dec}, pages={1665–1673} }
 @article{doerfler_edens_mann_parkhurst_havenstein_1997, title={Hepatic glucose-6-phosphatase and serum glucose in turkeys with poult enteritis and mortality syndrome}, volume={76}, number={suppl. 1}, journal={Poultry Science}, author={Doerfler, R. E. and Edens, F. W. and Mann, S. E. and Parkhurst, C. R. and Havenstein, G. B.}, year={1997}, pages={538} }
 @misc{edens_parkhurst_casas_dobrogosz_1997, title={Principles of ex ovo competitive exclusion and in ovo administration of Lactobacillus reuteri}, volume={76}, ISSN={["1525-3171"]}, DOI={10.1093/ps/76.1.179}, abstractNote={The data that have been presented indicate that the in ovo use of competitive exclusion (CE) agents is feasible for both chickens and turkeys. However, there are many pitfalls that await the use of in ovo application of CE agents, including the use of nonspecies-specific intestinal microbes and the use of harmful proteolytic, gas-producing and toxin-producing intestinal microbes. Of the potential CE agents that have posthatch application, only Lactobacillus reuteri has been shown to be safe and effective in terms of not affecting hatchability and in having a prolonged effect in the hatched chick or poult. Lactobacillus reuteri administration in ovo increases its rate of intestinal colonization and decreases the colonization of Salmonella and Escherichia coli in both chicks and poults. Additionally, mortality due to in-hatcher exposure to E. coli or Salmonella is reduced with in ovo L. reuteri. Use of antibiotics in ovo may preclude the use of co-administered CE agents, but Gentamicin and L. reuteri are a compatible mixture when administered in ovo in separate compartments. Nevertheless, the intestinal morphology can be affected by both the CE agent and by antibiotics. Lactobacillus reuteri both in ovo and ex ovo will increase villus height and crypt depth, and Gentamicin in ovo causes a shortening and blunting of the villus. Both Gentamicin and L. reuteri in ovo suppress potentially pathogenic enteric microbes, but with diminished antibiotic effects shortening and blunting of the intestinal villi does not correct itself. Goblet cell numbers increase significantly on the ileum villus of chicks treated with Gentamicin in ovo, and this is presumably due to the increase in potentially pathogenic bacteria in the intestinal tract. Diminishing antibiotic effects posthatch would then negatively affect the absorption of nutrients and reduce growth at least in a transitory manner. Thus, L reuteri administration in ovo singly or in combination with Gentamicin followed by L reuteri via drinking water or feed appears to have potential to control many enteric pathogens in poultry. Additional work in the use of in ovo CE cultures is mandated because there is a world-wide movement to reduce antibiotic use in poultry due to increased microbial resistance to antibiotics. Use of naturally occurring intestinal bacterial cultures, either in mixed culture or as single well-defined cultures, has potential for immediate use in the poultry industry.}, number={1}, journal={POULTRY SCIENCE}, author={Edens, FW and Parkhurst, CR and Casas, IA and Dobrogosz, WJ}, year={1997}, month={Jan}, pages={179–196} }
 @article{edens_qureshi_mann_parkhurst_havenstein_1997, title={The evolvement of Eosinophils in the pathogenesis of poult enteritis mortality syndrome}, volume={76}, number={suppl. 1}, journal={Poultry Science}, author={Edens, F. W. and Qureshi, M. A. and Mann, S. E. and Parkhurst, C. R. and Havenstein, G. B.}, year={1997}, pages={535} }
 @book{mountney_parkhurst_1995, title={Poultry products technology}, ISBN={1560228563}, publisher={New York: Food Products Press}, author={Mountney, G. J. and Parkhurst, C. R.}, year={1995} }
 @article{parkhurst_hamilton_ademoyero_1992, title={ABNORMAL FEATHERING OF CHICKS CAUSED BY SCIRPENOL MYCOTOXINS DIFFERING IN DEGREE OF ACETYLATION}, volume={71}, ISSN={["0032-5791"]}, DOI={10.3382/ps.0710833}, abstractNote={Graded levels of the Fusarium mycotoxins, scirpentriol (STO), 15-monoacetoxyscirpenol (15-MAS), 4,15-diacetoxyscirpenol (4,15-DAS), and 3,4,15-triacetoxyscirpenol (TAS), were fed to chicks until 3 wk of age. The primary wing feathers, which were scored visually on a scale of 1 to 5 using a newly created scoring scheme, were altered in a dose-related fashion by 15-MAS [minimum effective dose (MED) = .5 microgram/g diet], 4,15-DAS (MED = 2 micrograms/g), and STO (MED = 4 micrograms/g) but not by TAS (MED greater than 8 micrograms/g). The minimum growth inhibitory doses were 2 micrograms/g for STO, 15-MAS, and 4,15-DAS and 8 micrograms/g for TAS. The main alteration of the feathers was a frayed and missing web on the medial side of the distal half of the feather. The shafts of the feathers tended to have an accentuated medial curve. These results imply that the feather alterations associated with corn and feed infested with Fusarium spp. might be caused by trichothecene mycotoxins such as the scirpenols.}, number={5}, journal={POULTRY SCIENCE}, author={PARKHURST, CR and HAMILTON, PB and ADEMOYERO, AA}, year={1992}, month={May}, pages={833–837} }
 @article{parkhurst_1990, title={Farm flocks: Nutritional considerations of the small flock}, volume={45}, number={3}, journal={Large Animal Veterinarian}, author={Parkhurst, C. R.}, year={1990}, pages={16} }
 @article{parkhurst_baughman_thaxton_garlich_edens_1977, title={COMPARISON OF BROILERS GROWN IN ENVIRONMENTALLY MODIFIED AND CONVENTIONAL HOUSING AT DIFFERENT POPULATION DENSITIES 1,2 .1. PRODUCTION PERFORMANCE AND ECONOMIC-ANALYSIS}, volume={56}, ISSN={["1525-3171"]}, DOI={10.3382/ps.0560883}, abstractNote={Abstract A study was conducted to evaluate the economic feasibility of rearing broilers in environmentally modified versus conventional houses. Three broiler production trials involved over 27,000 broilers were conducted using densities of .07 sq. meter and .06 sq. meter per bird. There were two replicates of each density in each of the two houses in three separate trials. The control house in this study was a conventional, uninsulated, drop-curtain sided house with a dirt floor. The environmentally modified house was enclosed with metal siding insulated in the side walls and ceiling, and ventilated with thermostatically controlled fixed and variable speed fans. Body weight and feed conversion were significantly improved in the environmentally modified house. Mortality was significantly decreased in the environmentally modified house. Bird density did not influence performance in this study. An economic analysis indicated that the added initial cost of environmentally modified housing should be recovered in three and one-half years.}, number={3}, journal={POULTRY SCIENCE}, author={PARKHURST, CR and BAUGHMAN, GR and THAXTON, JP and GARLICH, JD and EDENS, FW}, year={1977}, pages={883–885} }
 @article{parkhurs.cr_1974, title={COMPARISON OF BROILER BREEDERS HOUSED ON FULL AND PARTIAL SLAT FLOORS}, volume={53}, ISSN={["0032-5791"]}, DOI={10.3382/ps.0530953}, abstractNote={Abstract Four experimental strains of Pilch-DeKalb broiler breeder females were housed at 23 weeks of age on full slat floors or partial slat floors (50–50 combination of slat-litter). Sixteen pens housing 40 females each were used in the study allowing 2.5 square feet (0.23 square meter) per female. Five males were added to each pen and maintained at that level by replacement. A commercial broiler breeder diet was fed on a restricted basis as recommended by the breeder. Records were kept on the basis of 28-day periods for egg production, mortality, fertility and hatchability. A sample of eggs was incubated each reporting period to test fertility and hatchability. Egg production was higher for hens housed on partial slat floors but it was not significant based upon P ≤ 0.05. Fertility was slightly lower initially for birds housed on the full slats and again during the last third of the trial. There were no significant differences in mortality for the breeder males or females housed on full slats as compared to partial slats.}, number={3}, journal={POULTRY SCIENCE}, author={PARKHURS.CR}, year={1974}, pages={953–956} }