@article{williams_pickworth_weaver_poole_2024, title={136 Evaluation of internal parasite burden in grazing beef cattle in North Carolina over a production lifecycle}, volume={102}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skae019.079}, abstractNote={Abstract Gastrointestinal nematode (GIN) parasite infections can be detrimental to not only cattle health and immunity, but also result in economic loss and poor performance. Cattle grazing in the southeast are challenged even further by the favorable environmental conditions for parasite development, especially those animals who have yet to develop an immunity to combat parasitism. To diminish potential economic and performance-based losses, many beef producers treat animals for GIN parasites with anthelmintics on a regular basis without proper diagnosis. Anthelmintic resistance(AR) develops when deworming products are overused and misused. To minimize the development of AR, selective deworming and sustainable management practices should be implemented. However, the severity of parasite burden over the production cycle needs to be better understood in beef cattle herds before recommendations can be made. Thus, the objective was to investigate the rates of GIN parasite infections through fecal egg counts (FEC) and the impact on body weight (BW) and body condition score (BCS). Angus-based cattle (6 mo-13 yr, n = 1,154) on a were utilized from five different research and educational herds across North Carolina. Cattle were categorized based on their age at the start of the project as either calves (n = 446), yearling heifers (n = 205), 2 year old (n = 260), 3-5 year old (n = 501), or 6+ year old (n = 206). Starting in September, FEC, BW, and BCS were collected and analyzed every 90 d at critical production timepoints (calving, breeding, weaning, and 90d post-weaning) to monitor the severity of GIN parasite challenge. Cattle on study were not treated with anthelmintics regardless of parasite load, with the exception of calves at four of the locations at the time of weaning. All data were analyzed using Proc MIXED in SAS with repeated measures. Statistical significance was declared at P ≤ 0.05 and a trend at 0.10 > P > 0.05. Age of cattle had an impact on FEC overall (P < 0.05), however, there was no difference between FEC of mature cattle over 3 yr (4.29 ± 4.9 eggs/gm). Calves had the greatest FEC (120.59 ± 4.2 eggs/gm) while cattle 6+ yr had the least (3.68 ± 4.5 eggs/gm). Cattle age at each location affected BCS and BW (P < 0.05). Between age groups across locations, time had an impact on FEC, BW, and BCS (P < 0.05). There was also a tendency (P = 0.6) for location to impact FEC. Calf sex did not affect (P > 0.05) FEC. Further FEC analysis of cattle under 2 yrof age is required to better understand when a natural immune response to GIN parasite infections develops.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Williams, Katherine G. and Pickworth, Carrie L. and Weaver, Andrew R. and Poole, Daniel H.}, year={2024}, month={Mar}, pages={67–68} } @article{haimon_poole_newsome_brown_dudley_poole_2024, title={Examining the long-term impacts of ergot alkaloids on fetal heifer development and subsequent growth and reproductive performance}, volume={102}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skae210}, abstractNote={Consumption of toxic endophyte-infected tall fescue (EI) results in poor reproductive performance in domestic livestock. In this study, the objective was to evaluate the effects of ergovaline exposure during mid-gestation (days 93 through 188 of gestation) on dam performance, the growing female fetus, and the subsequent growth and reproductive performance of the gestationally exposed heifer calves. Pregnant Angus and Simmental-Angus cows were blocked by age (2 to 3, to 7, and >7 y), body weight (BW), and breed; and then randomly assigned to graze either novel endophyte-infected tall fescue (EN; <5% infection rate; n = 27 year 1, n = 16 year 2) or toxic EI (99% infection rate; n = 27 year 1, n = 17 year 2). Weekly BW, body condition scores (BCS), hair coat scores, hair shedding scores (HSS), and blood samples for progesterone (P4) analysis were collected from mid-April through July of 2017 (year 1) and 2018 (year 2). Gestation length, birth weight, placental characteristics, heifer calf growth, onset of puberty, ovarian characteristics, and artificial insemination pregnancy rates were measured. Data were analyzed using the MIXED procedure of SAS. Cows grazing EI pastures had reduced average daily gain, reduced BCS, greater HSS, and decreased P4 concentrations compared to cows on EN pasture (P < 0.01). Birth weights were decreased for heifers whose dams were exposed to EI pastures during their second trimester (P < 0.01). Heifer pregnancy rates were not impacted by EI pasture exposure during gestation for either year of the study. However, a treatment-by-year effect was seen for the pregnancy rate for EI-exposed heifers in year 2; EI-exposed heifers in year 2 had increased pregnancy rates at two of the inseminations. Combined, these data reinforce that consumption of toxic EI during gestation can negatively impact both dam and offspring performance. More studies are needed to evaluate more parameters in an effort to elucidate the possible life-long impacts of ergovaline exposure during gestation.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Haimon, McKenzie L. J. and Poole, Rebecca K. and Newsome, McKayla A. and Brown, Alecia R. and Dudley, Harrison and Poole, Daniel H.}, year={2024}, month={Aug} } @article{rajo-gomez_giurgis_pickworth_weaver_foster_khanal_poole_2024, title={Exploring the impacts of fescue toxicosis on the pulmonary arterial pressure of angus cows}, volume={102}, ISSN={["1525-3163"]}, url={http://dx.doi.org/10.1093/jas/skae279}, DOI={10.1093/jas/skae279}, abstractNote={Abstract Vasoconstriction of peripheral blood vessels is one of the hallmark symptoms of fescue toxicosis in cattle. Thus, it was hypothesized that exposure to ergot alkaloids would increase the pulmonary arterial pressure (PAP). The objectives of this study were to examine the relationship between PAP and different physiological parameters of cows grazing either endophyte-infected (EI) or novel-endophyte (EN) fescue, then evaluate changes in PAP and other physiological measurements in cows exposed to EI pastures and deemed as susceptible or tolerant based on animal performance. Pregnant Angus cows at two different locations grazed either EI or EN fescue pastures for 14 consecutive weeks starting in early April of 2022. Forage measurements were collected to assess ergot alkaloid exposure throughout the study. In addition to measuring PAP, weekly measurements and blood samples were collected to evaluate physiological responses to ergot alkaloid consumption. The Fescue Toxicosis Selection Method (FTSM) was used for a post hoc analysis to identify cattle as either tolerant (EI-TOL) or susceptible (EI-SUS) when challenged with ergot alkaloid exposure. Data were analyzed using a MIXED procedure of SAS with repeated measures. Cows grazing on EN pastures had greater mean PAP values than EI cows, (P < 0.01), whereas a location effect was identified when comparing both EI-TOL and EI-SUS groups (P < 0.01). Cows exposed to EN pastures had greater ADG (P = 0.04) and progesterone (P4) concentrations (P < 0.01), and lower hair shedding scores (HSS; P < 0.01) than EI cows. The EI-TOL cows tended to have greater final BW, ADG, and had lower HSS (P < 0.01) than EI-SUS cows. While cattle consuming EI tall fescue exhibited classical physiological changes, the decrease in PAP of cattle consuming EI fescue was unexpected and contradicts the initial hypothesis. Furthermore, the FTSM provides a means to identify animals with superior performance in spite of the chronic exposure to ergot alkaloids. Continued investigations examining the interaction between ergot alkaloid exposure on cardiovascular parameters will lead to a fuller understanding of the disease, and are pivotal for developing innovative strategies that enhance best management practices to help guarantee the sustainability of the U.S. beef industry.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Rajo-Gomez, E. Benjamin and Giurgis, Mariam and Pickworth, Carrie L. and Weaver, Andrew R. and Foster, Derek M. and Khanal, Piush and Poole, Daniel H.}, year={2024}, month={Oct} } @article{rajo_weaver_pickworth_foster_poole_2024, title={Exposure to ergot alkaloids and heat stress alter pulmonary arterial pressure and nutritional intake in beef heifers}, volume={102}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skae234.312}, abstractNote={Abstract Ergot alkaloid consumption is detrimental to cattle as it negatively impacts several physiological and performance parameters. The objective of this study was to evaluate changes in nutritional intake and different physiological and performance parameters of heifers consuming an ergot alkaloid-infected ration. Purebred Angus heifers (216.3 ± 6.1 kg; 9 to 11 mo of age; n = 36) were randomly separated and fed either an endophyte-infected (EI) or endophyte-free (EF) total mixed ration (TMR) for 49 d. On d 1, iButton temperature data loggers were inserted intravaginally to record temperature on a 20-min frequency throughout the entire study. Individual feed and water intake was measured utilizing the Vytelle Sense system. Hourly environmental temperature and relative humidity measurements were utilized to calculate the temperature-humidity index (THI) and define exposure to heat stress as Thermoneutral (NO-HS), Mild (MILD-HS) and Moderate (MOD-HS). Pulmonary arterial pressure (PAP) was measured every 20 d to assess its response to ergot alkaloid and heat stress exposure. Additionally, weekly measurements were collected to monitor growth and physiological responses to EI-TMR intake. Data were analyzed using a MIXED procedure of SAS with repeated measures. The effects of treatment, day, THI and its interactions were evaluated for body weight (BW), average daily gain (ADG), body condition score (BCS), hair shedding score (HSS), vaginal temperature (VT), feed intake (FI), water intake (WI) and PAP. EF heifers had significantly less HSS and greater BW, ADG, and BCS than EI heifers over time (P < 0.0001). EF heifers also had lower VT than EI heifers (39.5 ± 0.1 vs 40.1 ± 0.1° C; P < 0.0001) and had reduced daily WI (8.3 ± 0.4 vs 9.4 ± 0.4 L; P < 0.0001). Moreover, WI was also found to be positively correlated to THI, as both EF and EI groups significantly increased (P < 0.0001) their WI as THI increased from NO-HS (5.9 ± 0.6 vs 7.4 ± 0.6 L) to MILD-HS (9.4 ± 0.6 vs 10.8 ± 0.6 L) and MOD-HS (12.8 ± 0.6 vs 13.4 ± 0.6 L). EF heifers also had greater daily FI than EI heifers (18.8 ± 0.6 vs 12.9 ± 0.6 kg; P < 0.0001), and FI was also affected by THI as intake in both EF and EI groups decreased when transitioning from NO-HS (21.3 ± 0.6 vs 14.6 ± 0.6 kg) to MILD-HS (16.4 ± 0.6 vs 11.1 ± 0.6 kg; P < 0.0001). PAP results tended to differ between groups (29.6 ± 0.6 vs 31.1 ± 0.6 mm Hg; P = 0.0954) and increased in both EF and EI groups when transitioning from MILD-HS (27.2 ± 0.9 vs 26.2 ± 0.9 mm Hg) to NO-HS (34.8 ± 0.9 vs 36.4 ± 0.9 mm Hg; P = 0.0147). Based on these data, exposure to ergot alkaloids negatively affects animal performance as it decreases ADG, BCS and increases HSS and VT, and it also increases daily WI and reduces daily FI. Furthermore, PAP, WI and FI were also negatively impacted by changes in THI and exposure to heat stress. Additional research is necessary to understand the interactions between these variables to identify efficiency parameters.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Rajo, Edwin Benjamin and Weaver, Andrew R. and Pickworth, Carrie L. and Foster, Derek and Poole, Daniel H.}, year={2024}, month={Sep}, pages={271–272} } @article{giurgis_mccann-deshazer_gadsby_poole_2024, title={Impact of progesterone signaling on tumor necrosis factor-alpha synthesis by luteal macrophages}, volume={102}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skae019.066}, abstractNote={Abstract Understanding the mechanism in which luteolysis occurs is an important step in improving the reproduction of livestock in the industry. The corpus luteum (CL) is a transient endocrine organ found on the ovary responsible for progesterone secretion. It is well known that prostaglandin F2-alpha (PGF) is responsible for luteal regression, however, the process by which luteal cells (LC) become sensitive to the luteolytic effects of PGF remain unclear. Therefore, the objective of this study was to determine if suppression of progesterone (P4) synthesis or blocking P4 signaling activates tumor necrosis factor (TNF)-alpha production by the luteal macrophages. Ovaries were collected from an abattoir and transported to the laboratory on ice. Ovary status (i.e. approximate days post ovulation), was determined by phenotypic description of ovarian structures. Only ovaries (n = 5) containing midcycle (d 12/13 post ovulation) CL were used in these experiments. Luteal tissue was isolated and dissociated to collect LC and and luteal macrophages (MAC). Isolated cells were incubated independently at 37°C at 5% CO2 for 24 h in 24-well plates. Luteal cells and MACs were then harvested and placed in the following conditions: 1) LC + MAC + DMSO (control), 2) LC + MAC + trilostane (TRIL 1.0mg/mL), 3) LC + MAC + TRIL 1.5 mg/mL, 4) MACS only, 5) MACS +LPS. Supernatant was harvested at 24 h whereas both cells and supernatant were harvested after 48 h, in vitro. Supernatant was immediately frozen for subsequent P4 analysis, via RIA. Data results were analyzed using a MIXED procedure of SAS and evaluated the effects of cell-type, treatment, and culture time. Statistical significance was determined at P < 0.05 and a tendency at 0.05 < P < 0.10. Overall, TRIL treatment reduced supernatant P4 concentration (8.3 and 6.8 ng/mL to 1.0 and 1.5 mg/mL TRIL, respectively) compared with controls (22.8 ng/mL; P = 0.0012); however there was not a difference when comparing the TRIL treated cultures. Progesterone concentrations tended to decrease over time (P = 0.0661). At 24 h in vitro, P4 concentrations were suppressed in 1.0 mg/mL TRIL and 1.5 mg/mL TRIL treated wells (5.3 and 4.2 ng/mL, respectively), compared with controls (16.4 ng/mL; P = 0.0014). Whereas P4 concentrations were reduced in the 1.5 mg/mL TRIL treated wells (1.6 ng/mL) compared with controls (9.95 ng/mL; P = 0.0419) and tended to differ in the1.0 mg/mL TRIL treated wells (2.4 ng/mL; P = 0.0634), at 48 h in vitro. Progesterone concentrations were undetectable in wells containing MAC only. Collectively, TRIL treatment effectively reduced P4 synthesis in LC cultures. Therefore, the greater concentration of TRIL is needed for P4 suppression in longer term culture systems. Additional analyses will be conducted to determine the effect of P4 suppression on macrophage function.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Giurgis, Mariam and McCann-Deshazer, Madison and Gadsby, John E. and Poole, Daniel H.}, year={2024}, month={Mar}, pages={55–56} } @article{mullenix_gadberry_rhinehart_dillard_tucker_stewart_vendramini_poole_sanchez_mercadante_et al._2023, title={Awardee Talk: Foraging for Collaboration: Beef-Forage System Strengths Unite Research and Extension Efforts in the Asas Southern Section}, volume={101}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skad281.187}, abstractNote={Abstract The American Society of Animal Science Southern Section has a rich history of collaboration and hosts an annual professional development meeting for ASAS members. The Section meeting includes scientific presentations, academic quadrathlon, undergraduate and graduate student competitions, symposia, and networking opportunities for its members. The Section has used strategic collaborations to foster multi-state projects and initiatives. One of the key discipline focus areas of the Section is forage-based beef production systems. The Section holds two symposia focused on research, Extension, and industry topics related to beef cattle management. The Bill E. Kunkle Interdisciplinary Symposium was started in 2014 to honor the impact of Dr. Kunkle, University of Florida, and fosters multi-disciplinary communication of beef cattle science. The SERA 41 Symposium is part of the regional NIMSS project focus-group on improving production efficiency of the beef cow herd in the Southeast US. The NIMSS group works collectively to create partnerships and common goal-oriented projects across the Southern Section states. The section is also home to the Randel Physiology Lecture series which was formed in 2016 to highlight Dr. Ron Randel’s commitment to the Southern Section physiology section, and to promote high-quality science for the next generation of physiologists and endocrinologists. More than 25 peer-reviewed publications and several webinars have resulted from these symposia and invited lectureships. This creates a referenceable resource for scientists on emerging topics and identifies potential priority areas of focus for scientists within the Southern region. Another highlight of the Section is the collaborative work of the Extension committee. The Extension committee collaboratively fosters Extension program development across the Southern region. The committee developed a regional webinar series in 2015 for regional training of Extension agents on livestock and forage management topics. Subsequent in-service training courses have emerged through both virtual and in-person delivery. Training is primarily focused on forage-based livestock management systems. Through these opportunities, the Southern Section has remained a gathering point for professional engagement and should continue to evolve to meet the needs of animal scientists.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Mullenix, Kimberly and Gadberry, Shane and Rhinehart, Justin D. and Dillard, S. Leanne and Tucker, Jennifer J. J. and Stewart, Robert Lawton and Vendramini, Joao and Poole, Daniel H. and Sanchez, Nicole C. Burdick and Mercadante, Vitor R. G. and et al.}, year={2023}, month={Nov}, pages={152–153} } @article{rajo_williams_pickworth_foster_poole_2023, title={Exposure to Endophyte-Infected Tall Fescue Negatively Impacts Pulmonary Arterial Pressure in Beef Cattle}, volume={101}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skad068.077}, abstractNote={Abstract Fescue toxicosis negatively impacts cattle productivity. Previous data from our laboratory has demonstrated that cattle within a herd respond differently when grazing tall fescue, thus variation within a breed may provide genetic tolerance to the negative effects on performance. Fescue toxicosis results in major impacts on the cardiovascular system, thus it was hypothesized that exposure to ergot alkaloids negatively impacts pulmonary arterial pressure (PAP). The objective of this study was to examine changes in PAP and other production parameters in cattle consuming endophyte-infected tall fescue. Pregnant Angus cows (2 to 4 years; n = 65) were randomly divided to graze either endophyte-infected (EI) or novel endophyte (EN) pastures for4 consecutive weeks starting in April. Weekly measurements were collected to monitor physiological responses to consuming endophyte-infected tall fescue. In addition, PAP was measured every 4 weeks. Data were analyzed using a MIXED procedure of SAS, and statistical significance was determined at P < 0.05 and a tendency at 0.05 < P < 0.10, and evaluated the effects of treatment, age, week, and its interactions on BW, ADG, BCS, HCS, HSS and PAP. Exposure to EI did not affect BW, ADG, or BCS (P >0.05). Whereas, hair coat scores (1-5 scale) were significantly less for cattle consuming EN pastures (2.15 ± 0.05) compared with consuming EI pastures (2.31 ± 0.05; P < 0.05). Additionally, shedding scores (1-5 scale) were reduced in cattle consuming EN pastures (2.3±0.05) compared with consuming EI pastures (2.5±0.05; P< 0.05). There was a significant difference in PAP measurements in cattle exposed to EN pastures (37.16 ± 0.59 mm Hg) compared with EI pastures (31.31 ± 0.56 mm Hg; P < 0.0001). Additionally, PAP scores tended to deviate over the 14-week study between treatment groups (P = 0.0677). As expected, exposure to EI tall fescue resulted in greater HCS and HSS. However, the decrease in PAP in cattle consuming EI fescue was unexpected. Thus, further investigations are needed to examine the interaction between ergot alkaloid exposure on cardiovascular parameters such as PAP to potentially predict genetic differences in beef cattle to identify animals that would have a lower risk of developing fescue toxicosis.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Rajo, Edwin Benjamin and Williams, Katherine and Pickworth, Carrie L. and Foster, Derek and Poole, Daniel H.}, year={2023}, month={May} } @article{williams_rajo_weaver_poole_pickworth_2023, title={Impact of Fescue Variety on Fecal Egg Counts in Mature Beef Cattle}, volume={101}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skad068.093}, abstractNote={Abstract Fescue toxicosis decreases beef cattle performance in a multitude of ways, including decreased health and immunity. Cattle challenged by fescue toxicosis are often grazing in an environment favorable for development of gastrointestinal nematodes (GIN). Interactions of fescue toxicosis and parasite challenge may result in further performance and economic losses. Many beef producers treat animals regularly for GIN parasites with little insight on necessity or effectiveness of anthelmintic products. Overuse of anthelmintics can result in development of anthelmintic resistance in GIN populations. To minimize the development of anthelmintic resistance, implementation of selective deworming practices should be considered. However, level of parasite burden and effects of fescue toxicosis on parasite burden need to be better understood in beef cattle herds before recommendations can be offered. Therefore, the objective was to investigate the impact of fescue toxicosis on GIN parasite infection rates through fecal egg counts (FEC), body weight (BW), hematocrit (HCT), and body condition score (BCS). Starting in April, for 14 consecutive weeks post-weaning, pregnant Angus-based cows (2 to 4 years old, n = 65) were rotationally grazed on either novel endophyte (EN) fescue or endophyte-infected (EI) fescue pastures. Hematocrit, BCS, and BW were assessed weekly, while FEC were measured bi-weekly to monitor the physiological changes as a result of consuming endophyte-infected tall fescue. All data were analyzed using Proc MIXED in SAS with repeated measures. Statistical significance was declared at P ≤ 0.05 and a trend at 0.10 > P > 0.05. Overall, FEC were low (4.2 ± 0.9 eggs/gm) in these mature cattle and grazing EI or EN fescue did not have any overall effect (P > 0.05) on the FEC. However, FEC decreased (P < 0.05) over the course of the study from week 1 to week 13. Body weight, HCT, and BCS were not affected (P > 0.05) by the type of fescue grazed. There was a tendency (P < 0.10) for 2-3 and 4-6 year old cattle to have lower BW when grazing EI compared with EN fescue while cattle >7 were not affected. Cattle gained BW (P < 0.05) over the 14-week study (471.4 and 527.7 ± 0.6 kg, 0 and4 week respectively). For cattle grazing EI fescue, HCT linearly decreased (P < 0.05) from week 1 to week 14 whereas cattle grazing EN fescue had a linear increase (P < 0.05) in HCT from week 1 to week 14. More research is warranted to investigate beef cattle FEC and the potential impact of fescue type on FEC in younger beef cattle.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Williams, Katherine and Rajo, Edwin Benjamin and Weaver, Andrew R. and Poole, Daniel H. and Pickworth, Carrie L.}, year={2023}, month={May} } @article{koester_poole_serao_schmitz-esser_2020, title={Beef cattle that respond differently to fescue toxicosis have distinct gastrointestinal tract microbiota}, volume={15}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0229192}, abstractNote={Tall fescue (Lolium arundinaceum) is a widely used forage grass which shares a symbiosis with the endophytic fungus Epichloë coenophiala. The endophyte produces an alkaloid toxin that provides herbivory, heat and drought resistance to the grass, but can cause fescue toxicosis in grazing livestock. Fescue toxicosis can lead to reduced weight gain and milk yields resulting in significant losses to the livestock industry. In this trial, 149 Angus cows across two farms were continuously exposed to toxic, endophyte-infected, fescue for a total of 13 weeks. Of those 149 cows, 40 were classified into either high (HT) or low (LT) tolerance groups according to their growth performance (weight gain). 20 HT and 20 LT cattle balanced by farm were selected for 16S rRNA gene and ITS1 region Illumina MiSeq amplicon sequencing to compare the fecal microbiota of the two tolerance groups. This study reveals significantly (P<0.05) different bacterial and fungal microbiota between HT and LT cattle, and indicates that fungal phylotypes may be important for an animal’s response to fescue toxicosis: We found that fungal phylotypes affiliating to the Neocallimastigaceae, which are known to be important fiber-degrading fungi, were consistently more abundant in the HT cattle. Whereas fungal phylotypes related to the genus Thelebolus were more abundant in the LT cattle. This study also found more pronounced shifts in the microbiota in animals receiving higher amounts of the toxin. We identified fungal phylotypes which were consistently more abundant either in HT or LT cattle and may thus be associated with the respective animal’s response to fescue toxicosis. Our results thus suggest that some fungal phylotypes might be involved in mitigating fescue toxicosis. The results of our study provide a basis for investigating the functional role of the gastrointestinal microbiota in fescue toxicosis in more detail in the future.}, number={7}, journal={PLOS ONE}, author={Koester, Lucas R. and Poole, Daniel H. and Serao, Nick V. L. and Schmitz-Esser, Stephan}, year={2020}, month={Jul} } @article{brown_haimon_poole_poore_poole_2020, title={Changes in Cytokine Profiles in Response to Ergovaline Exposure in Slick vs. Normal Hair Coat in Beef Heifers.}, volume={98}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz397.091}, abstractNote={Abstract Fescue toxicosis is a syndrome common in cattle grazing fescue containing an endophyte that produces ergot alkaloids. Our lab has previously demonstrated that chronic exposure of ergot alkaloids adversely effects innate immune response. Therefore, the objective of this study was to examine changes in cytokine profiles in heat tolerant heifers exposed to ergot alkaloids from endophyte-infected fescue compared to wildtype controls. Angus X Senepol heifers were blocked by weight and hair coat genotype, Slick (S) or Normal (N) then randomly fed novel endophyte fescue (EN) or endophyte-infected fescue (EI) haylage in a total mixed ration for 63d (n=5 per group). Weekly measurements were collected to monitor physiological responses during exposure to ergot alkaloids. Blood samples were collected for cytokine analysis on d 0, 14, 28 and 56. Cytokine concentrations were quantified using Quantibody® Bovine Cytokine Arrays. Data were analyzed using PROC MIXED of SAS with repeated measures. Statistical significance was determined at P< 0.05 and a tendency at 0.05< P< 0.10. Concentrations of TNF were greater in EN-S heifers (6.57 ng/ml) compared to other heifer groups (P< 0.05; 1.33, 2.34, 3.15 ng/ml for EN-N, EI-S, and EI-N, respectively). Concentrations of IL21 were greater in EN-S heifers (8.15 ng/ml) compared to other heifer groups (P< 0.05; 1.55, 3.43, 3.26 ng/ml for EN-N, EI-S, and EI-N, respectively). Concentrations of IFNA (P=0.0543), IFNG (P=0.0558), IL1F1 (P=0.0587), and IL1F5 (P=0.0738) tended to be greater in in EN-S heifers compared to other heifer groups. Interestingly, concentrations of chemokine CCL4 (953.5 vs. 183.7 pg/mL) and CXCL9 (2.57 vs. 0.69 ng/mL) were significantly greater in S heifers than N heifers (P< 0.05). No differences were observed for IL13 and CXCL10 (P >0.05). In contrast to previous data, exposure to ergovaline via endophyte-infected fescue, did not induce an innate immune response. Rather, cytokine concentrations were elevated in heifers with the slick hair genotype. Overall, developing a better understanding of the interaction between ergot alkaloids and the slick hair genotype will help to improve cattle health management.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Brown, Alecia R. and Haimon, McKenzie L. and Poole, Rebecca and Poore, Matt H. and Poole, Daniel H.}, year={2020}, month={Nov}, pages={40–40} } @article{anderson_holt_heugten_poole_2020, title={Changes in growth performance, feeding behaviors, and posture behaviors of growing pigs subjected to low-intensity heat stress}, volume={98}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skaa278.006}, abstractNote={Abstract This study was to determine the impact of low-intensity heat stress on frequency and duration of feeding, drinking, ventral lying, and lying lateral lying behaviors. Pigs (n = 64; 24.6 ± 3.7 kg BW) were housed four per pen in thermoneutral conditions (CON; 23.9 °C ± 2.5 °C) or constant high ambient temperatures (HS; 28.7 °C ± 1.3 °C) for 16 d, followed by thermoneutral conditions (24.4 °C ± 1.8 °C) for both groups through d 21, and subsequent heat stress (28.0 °C ± 3.0 °C) for both groups through d 30. Eight focal pigs (2 pens/treatment) were video-recorded on d 3, 6, 10, 13, 20, and 29 at three time periods (morning: 0600-0800, afternoon: 1200–1400, evening: 1800–2000). Heat stress reduced ADG (HS: 1.00 kg/d, CON: 1.13 kg/d; P = 0.020) from d 14 through d 21, tended to reduce ADFI (HS: 2.14 kg/d, CON: 2.24 kg/d; P = 0.085), and increased GF (HS: 0.62, CON: 0.52; P = 0.006) from d 1 through d 7. Surface body temperature from d 2 through d 15 was greater in HS than CON pigs (mean: 39.4 °C, 37.6 °C, respectively), and was lower on d 18 for HS than CON pigs (36.4 °C vs. 37.8 °C, respectively) and d 22 (38.6 °C vs 39.3 °C, respectively). A treatment x day x time interaction for feeding duration (P = 0.003) showed CON pigs spent longer at the feeder in the morning of d 6 than HS (22.70 min, 8.97 min, respectively), but CON spent less time than HS during d 6 evening (8.78 min, 19.57 min, respectively). HS pigs visited the feeder more frequently in the evening (14.4 bouts) than CON pigs (7.8 bouts; P = 0.029). Low-intensity heat stress negatively impacted performance and altered time of feeding duration and frequency, indicating feeding behavior may be a useful heat stress predictor.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Anderson, Lauren E. and Holt, Jonathan P. and Heugten, Eric and Poole, Daniel H.}, year={2020}, month={Nov}, pages={3–3} } @article{anderson_holt_heugten_poole_2020, title={Changes in serum cortisol concentrations and cytokine profiles of growing pigs subjected to low-intensity heat stress}, volume={98}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skaa278.480}, abstractNote={Abstract This study was to determine the impact of low-intensity heat stress on inflammatory biomarkers in serum, ileum, jejunum and lung lavage samples. Pigs (n = 64; 24.6 ± 3.7 kg BW) were housed four per pen in thermoneutral conditions (CON; 23.9°C ± 2.5°C) or constant high ambient temperatures (HS; 28.7°C ± 1.3°C) for 16 d, followed by thermoneutral conditions (24.4°C ± 1.8°C) for both groups through d 21, and subsequent heat stress (28.0°C ± 3.0°C) for both groups through d 30. Respiration rate (P < 0.01) was greater in HS than CON pigs from d 2 through d 15 (mean: 82.54 breaths/min vs. 59.26 breaths/min). HS pigs had greater cortisol concentration (40.1 ng/mL vs. 27.3 ng/mL) than CON on d 2, but lower concentrations on d 22 (32.9 ng/mL vs. 48.9 ng/mL) and d 25 (25.4 ng/mL vs. 42.0 ng/mL; treatment x day: P < 0.001). HS pigs tended to have greater serum IL1β (190.1 vs. 143.4 pg/mL; P = 0.06) and greater serum IL12 concentrations (914.9 vs. 785.4 pg/mL; P < 0.01) than CON pigs. HS pigs tended to have greater ileal mucosa IL6 concentrations than CON pigs (50.4 vs. 30.9 pg/mL; P = 0.08). Jejunal mucosa IL1α concentrations tended (P = 0.10) to be greater for CON than HS pigs (13.5 vs. 9.0 pg/mL) and CON pigs had greater jejunal IL12 concentrations (18.1 vs. 11.8 pg/mL) than HS pigs (P = 0.02). Bronchioalveolar lavage from HS pigs tended (P = 0.10) to have a greater granulocyte-macrophage colony-stimulating factor concentration (6.9 vs. 5.3 pg/mL) than CON pigs and had greater IL4 (7.7 vs. 4.2 pg/mL) and IL12 concentrations (34.8 vs. 24.5 pg/mL) than CON pigs (P = 0.01). Increased inflammatory activity and endocrine stress response occurred during low-intensity heat stress, indicating it may be more detrimental than previously accepted.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Anderson, Lauren E. and Holt, Jonathan P. and Heugten, Eric and Poole, Daniel H.}, year={2020}, month={Nov}, pages={266–266} } @article{poole_mayberry_newsome_poole_galliou_khanal_poore_serao_2020, title={Evaluation of Resistance to Fescue Toxicosis in Purebred Angus Cattle Utilizing Animal Performance and Cytokine Response}, volume={12}, ISSN={["2072-6651"]}, DOI={10.3390/toxins12120796}, abstractNote={Fescue toxicosis is a multifaceted syndrome common in cattle grazing endophyte-infected tall fescue; however, varying symptomatic responses potentially imply genetic tolerance to the syndrome. It was hypothesized that a subpopulation of animals within a herd would develop tolerance to ergot alkaloid toxicity. Therefore, the goals of this study were to develop selection criteria to identify tolerant and susceptible animals within a herd based on animal performance, and then examine responsive phenotypic and cytokine profiles to fescue toxicosis. Angus cows grazed endophyte-infected tall fescue at two locations for 13 weeks starting in mid-April 2016. Forage measurements were collected to evaluate ergot alkaloid exposure during the study. A post hoc analysis of animal performance was utilized to designate cattle into either tolerant or susceptible groups, and weekly physiological measurements and blood samples were collected to evaluate responses to chronic exposure to endophyte-infected tall fescue. Findings from this study support the proposed fescue toxicosis selection method formulated herein, could accurately distinguish between tolerant and susceptible animals based on the performance parameters in cattle chronically exposed to ergot alkaloids, and provides evidence to warrant additional analysis to examine the impact of ergot alkaloids on immune responsiveness in cattle experiencing fescue toxicosis.}, number={12}, journal={TOXINS}, author={Poole, Daniel H. and Mayberry, Kyle J. and Newsome, McKayla and Poole, Rebecca K. and Galliou, Justine M. and Khanal, Piush and Poore, Matthew H. and Serao, Nick V. L.}, year={2020}, month={Dec} } @article{galliou_khanal_mayberry_poore_poole_serao_2020, title={Evaluation of a commercial genetic test for fescue toxicosis in pregnant Angus beef cattle}, volume={4}, ISSN={["2573-2102"]}, DOI={10.1093/tas/txaa181}, abstractNote={Abstract Most tall fescue [Lolium arundinaceum (Schreb.) Darbysh] in the Southeastern United States contains an endophyte that causes fescue toxicosis (FT) in grazing animals, a serious disease that causes approximately $1 billion in economic losses to the animal industries in the United States. Recently, a genetic test called T-Snip (AgBotanica, LCC, Columbia, MO), was developed with the objective of identifying animals with genetic variation for FT tolerance. The aim of this study was to validate the use of this genetic test in mature, pregnant cows. Over 13 wk, weekly phenotypic data, including body weight, rectal temperatures, hair coat scores, hair shedding scores, and body condition scores, were collected on 148 pregnant purebred Angus cows at 2 locations in NC where infected fescue was the primary source of feed. Birth weights (cBW) and 205-d adjusted weaning weights (adjWW) from these cow’s calves were recorded. All cows were genotyped for T-Snip. At the end of the trial, each phenotypic trait was calculated as the slope of the linear regression of performance on weeks. The effect of T-Snip rating genotypes (4 levels) on slope traits was tested using a linear model also including the fixed-effects of location, parity, and the initial measurement for each trait (covariate). For cBW and adjWW, the model also included the sex of the calf and the month of birth as categorical effects. Associations of T-Snip genotypes were observed for body weight gain (aBWd) of pregnant cows (P = 0.15; interaction with location), change in body condition score (aBCSd; P = 0.13), and adjWW (P = 0.06; interaction with location). For aBWd and adjWW, associations were found just within one location (P = 0.017 and 0.047, respectively), which was the location with higher endophyte infection rate. For all associations, the direction of the T-Snip genotypes was the same and as expected: the greater the genotype score, the better performance. No associations were found for the other traits (P > 0.10). These results indicate that the T-Snip test may be predictive of cow performance (aBWd, aBCSd, and adjWW) in an endophyte-infected tall fescue environment.}, number={4}, journal={TRANSLATIONAL ANIMAL SCIENCE}, author={Galliou, Justine M. and Khanal, Piush and Mayberry, Kyle and Poore, Matt H. and Poole, Daniel H. and Serao, Nick V. L.}, year={2020}, month={Oct} } @article{haimon_brown_poore_poole_2020, title={In Utero Exposure of Ergot Alkaloids does not Impact Heifer Growth and Reproductive Performance.}, volume={98}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz397.101}, abstractNote={Abstract In utero exposure to toxins can alter fetal development and postnatal performance. The objective of this study was to investigate the effects of in utero exposure of ergot alkaloids via endophyte-infected (EI) fescue diets during gestation on heifer growth, onset of puberty, ovarian characteristics and AI pregnancy rates. Pregnant Angus and SimAngus cows grazed either endophyte-free (EF) or EI pastures on d90-180 of gestation. Assessment of puberty of heifer (n = 40) via measurement of BW, BCS, reproductive tract scores (RTS), pelvic area (PA) and weekly blood sample for progesterone (P4) analysis started at 10 mo of age. At 14 mos of age, all heifers were synchronized using the CoSynch+7d CIDR protocol and inseminated to examine reproductive measurements, follicle mapping and AI pregnancy rate. Data were analyzed using a MIXED procedure of SAS and examined for effects of EI, sire, and age. Statistical significance was determined at P < 0.05 and a tendency at 0.05 < P < 0.10. In utero exposure to EI did not affect ADG, BW, or BCS (P > 0.05) however, there was a sire by treatment interaction for ADG during onset of puberty (P < 0.05). While EI did not affect PA or RTS (P > 0.05), sire significantly influenced RTS and PA (P < 0.05) thus impacting of onset of puberty. Based on P4 concentrations, only 55% of all heifers were cyclic by 14 months of age and there was a sire by treatment interaction for onset of puberty (P < 0.05). No differences were observes in AI pregnancy rate between heifer groups (EF 39.5±7; EI, 43.7±7; P >0.05). While EI did not affect follicle counts or luteal area (P > 0.05), sire significantly influenced the percentage of preselected (2-4mm) and selected (>9mm), but not transitional (5-8mm), ovarian follicles at breeding age (P < 0.05). While consumption of EI fescue during gestation impacts cow performance and onset of puberty in heifers, it has minimal effect on heifer growth and reproductive development and performance.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Haimon, McKenzie L. and Brown, Alecia R. and Poore, Matt H. and Poole, Daniel H.}, year={2020}, month={Nov}, pages={44–44} } @article{eisemann_ashwell_devine_poole_poore_linder_2020, title={Physiological response, function of sweat glands, and hair follicle cycling in cattle in response to fescue toxicosis and hair genotype}, volume={98}, ISSN={0021-8812 1525-3163}, url={http://dx.doi.org/10.1093/jas/skaa013}, DOI={10.1093/jas/skaa013}, abstractNote={AbstractFescue toxicosis is a syndrome that results when cattle consume toxic endophyte-infected tall fescue. The objective of this study was to compare the response in physiological variables, sweat gland function, hair follicle cycling, and gene expression to feeding a total mixed ration that included tall fescue haylage and tall fescue seed containing a toxic endophyte (EI) or tall fescue haylage containing a nontoxic novel endophyte (EN) in beef heifers (Angus × Senepol heifers, n = 31) with 2 different hair genotypes. Numbers in each subgroup were as follows: novel endophyte, heterozygous slick (EN-S; n = 8), novel endophyte, homozygous hairy (wild type, EN-W; n = 7), endophyte-infected, heterozygous slick (EI-S; n = 10), and endophyte-infected, homozygous hairy (wild type, EI-W; n = 6). Physiological measurements were taken weekly for 7 wk. Data were analyzed using the MIXED procedure of SAS including dietary fescue treatment (EN vs. EI) and hair genotype (S vs. W) as main effects, day as a repeated measure, and temperature–humidity index (THI) as a covariate. Skin biopsies were taken before treatment initiation and on day 37 of treatment. Average surface temperature (ST) increased as the THI increased (P < 0.0001). Average ST was greater (P < 0.01) for animals fed EI than for animals fed the EN fescue diet, and greater (P < 0.01) for animals with the W genotype compared with animals with the S genotype. The difference between heifers with the S and W genotype was greater at greater THI (genotype × day interaction, P < 0.01). Transepidermal water loss (TEWL) was greater (P < 0.05) for animals with the S genotype compared with the W genotype and greater (P < 0.05) for heifers with the S genotype than for heifers with the W genotype when fed EI (36.7, 38.5, 30.0, and 38.7 g/m2 per hour for EN-W, EN-S, EI-W, and EI-S, respectively). The fraction of follicles in telogen in plucked hair samples for heifers fed EI was greater for animals with the S genotype than the W genotype (fraction in telogen: 0.456, 0.565, 0.297, 0.702 for EN-W, EN-S, EI-W, and EI-S, respectively; diet × genotype interaction, P < 0.05). Fraction of follicles in anagen was the opposite. EI fescue resulted in increased ST, changes in hair follicle cycling that support greater hair growth, and decreased TEWL for heifers with the W genotype compared with S genotype, suggesting greater heat stress in response to EI.}, number={3}, journal={Journal of Animal Science}, publisher={Oxford University Press (OUP)}, author={Eisemann, J.H. and Ashwell, M.S. and Devine, T.L. and Poole, D.H. and Poore, M.H. and Linder, K.}, year={2020}, month={Mar} } @article{brown_poole_jackson_poore_pickworth_poole_2019, title={111 Changes in proinflammatory cytokines and chemokines in beef steers chronically exposed to endophyte-infected tall fescue seed}, volume={97}, ISSN={0021-8812 1525-3163}, url={http://dx.doi.org/10.1093/jas/skz053.095}, DOI={10.1093/jas/skz053.095}, abstractNote={Abstract Endophyte-infected tall fescue consumption adversely effects health and immune response. The aim of this study was to evaluate the impact of protein supplementation on cytokine response in steers consuming ergovaline, found in endophyte-infected tall fescue. Thirty-two beef steers were fed a total mixed ration (TMR) and randomly assigned to receive one of four treatments for 56 days: endophyte-free seed (0 ug/kg ergovaline) with either 18% (EF-18; n = 8) or 14% dietary protein (EF-14; n = 8) and endophyte-infected seed (500 ug/ kg ergovaline) with 18% (EI-18; n = 8) or 14% dietary protein (EI-14; n = 8). Blood samples were collected for cytokine analysis on d 28 and d 42 of the feeding period representing when steers vaccinated and boostered for bovine viral diarrhea (BVD) types 1 and 2 and infectious bovine rhinotracheitis (IBR). Cytokine concentrations were evaluated using Quantibody Bovine Cytokine Arrays. Data were analyzed using PROC MIXED of SAS with repeated measures. Statistical significance was determined at P0.05). Interestingly, concentrations of cytokines, IL13 (912±148 vs. 410.9±135 pg/mL) and IL21 (1636.0±295 vs. 629±305 pg/mL), which are involved in chronic inflammatory process were greater (P < 0.05) in EI steer compared to EF steers on d 28 and d 42. Concentrations of chemokine CCL4 and proinflammatory cytokines IFNG and IL-1alpha tended to be greater in EI steers compared to EF steers (P < 0.10). Overall, these data demonstrate that consumption of ergovaline increased proinflammatory cytokines and induced a chronic immune response. Developing a better understanding of overall immunity in cattle exposed to endophyte-infected tall fescue is fundamental to improve cattle health within the beef industry.}, number={Supplement_1}, journal={Journal of Animal Science}, publisher={Oxford University Press (OUP)}, author={Brown, Alecia R and Poole, Rebecca K and Jackson, McKenzie Lane and Poore, Matthew H and Pickworth, Carrie L and Poole, Daniel H}, year={2019}, month={Jul}, pages={42–43} } @article{davis_poole_poore_poole_pickworth_2019, title={47 Interaction of dietary protein and endophyte- infected Tall Fescue seed in stocker steers on finishing phase performance and carcass traits}, volume={97}, ISSN={0021-8812 1525-3163}, url={http://dx.doi.org/10.1093/jas/skz053.189}, DOI={10.1093/jas/skz053.189}, abstractNote={Abstract Fescue toxicosis is a multifaceted disease that negatively impacts cattle. It was hypothesized that exposure to endophyte-infected fescue during the stocker phase affects finishing phase growth and carcass characteristics. Eight-month-old steers were sorted by weight and randomly assigned to receive one of four treatments for 56 days in confinement: endophyte-free seed (0 ug/kg ergovaline) with either 18% (EF-18; n = 9) or 14% dietary protein (EF-14; n = 9) and endophyte-infected seed (500 ug/kg ergovaline) with 18% (EI-18; n = 9) or 14% dietary protein (EI-14; n = 9). Following fescue exposure calves were backgrounded on novel endophyte fescue pastures for 8 mo. At 18 mo, all steers were vaccinated, implanted, and reentered the feedlot for a 112 d growing phase and 52 d finishing phase. Body weight was recorded every 28 d and carcass data was collected at slaughter. Data were analyzed using the MIXED procedure of SAS for effects of BW, ADG, dressing percentage (DP), HCW, backfat, ribeye area (REA), KPH, USDA Yield grade (YG), and USDA Quality grade (QG). Statistical significance was determined at P > 0.05) HCW, BW, backfat, REA, DP, or QG. TheEI-14 had a greater ADG (1.69 kg/d) during the feedlot growing phase compared to the other treatment groups (1.53, 1.47, 1.55 for EI-18, EF-14, EF-18, respectively; P > 0.05). Steers stockered on 18% dietary protein had greater BW compared to steers previously fed at 14% (501.3±3.8 vs. 489.7±3.8; P = 0.0339). In addition, 18% protein in stocker diet resulted in greater KPH (2.3±0.2 vs. 1.78±0.2; P = 0.0129) and YG (3.4±0.1 vs. 3.0±0.1; P = 0.0168) compared with steers fed 14% dietary protein. Finishing growth and carcass characteristics were not affected by exposure to ergot alkaloids at weaning as much as dietary protein when cattle had a background period prior to feedlot entry}, number={Supplement_1}, journal={Journal of Animal Science}, publisher={Oxford University Press (OUP)}, author={Davis, Matthew E and Poole, Rebecca K and Poore, Matthew H and Poole, Daniel H and Pickworth, Carrie L}, year={2019}, month={Jul}, pages={83–83} } @article{poole_womble_poore_poole_pickworth_2019, title={Effects of endophyte-infected tall fescue seed and protein supplementation on stocker steers: I. Growth performance and hemodynamic responses}, volume={97}, ISSN={0021-8812 1525-3163}, url={http://dx.doi.org/10.1093/jas/skz249}, DOI={10.1093/jas/skz249}, abstractNote={Abstract Fescue toxicosis is a multifaceted syndrome common in cattle grazing endophyte-infected tall fescue and is detrimental to growth and performance. Recent research has shown that supplementing protein has the potential to enhance growth performance in weaned steers. Therefore, the objective of this study was to evaluate the effect of supplemental CP on physiological parameters in stocker steers experiencing fescue toxicosis. Thirty-six weaned Angus steers (6 mo of age) stratified by weight (196.1 ± 3.6 kg) were assigned to a 2 × 2 factorial arrangement for 56 d: endophyte-free (EF) seed and 14% CP (EF-14; n = 9), EF seed and 18% CP (EF-18; n = 9), endophyte-infected (EI) seed and 14% CP (EI-14; n = 9), and EI seed and 18% CP (EI-18; n = 9). Steer growth and hemodynamic responses were collected weekly during ergot alkaloid exposure. On day 14 of the trial, iButton temperature data loggers were subcutaneously inserted in the lateral neck region to record hourly body temperature for 42 d. Data were analyzed using PROC MIXED of SAS with repeated measures. No differences were observed in DMI, BW, ADG, F:G, or BCS during the treatment period (P > 0.05). Hair shedding scores, rectal temperatures, surface temperatures, and respiration rates were greater in EI steers compared to EF steers regardless of supplemental CP (P < 0.05). However, subcutaneous body temperature was greater in EI-14 steers (37.94 °C) compared to other steer groups (37.60, 37.68, 37.72 ± 0.04 °C for EF-14, EF-18, and EI-18, respectively; P < 0.05). Prolactin concentrations tended to be greater in EF steers when compared to EI steers (P = 0.07). Heart rate and hematocrit were reduced for EI-18 steers compared to other steer groups (P < 0.05). Caudal artery diameter was reduced in EI-18 steers compared to EI-14 steers (2.60 vs. 2.75 ± 0.05 mm, respectively; P < 0.05) and caudal vein diameter was reduced in EI-18 steers (3.20 mm) compared to all other steer groups (3.36, 3.39, 3.50 mm for EF-14, EF-18, and EI-14, respectively; P < 0.05). However, there was no difference observed in systolic or diastolic blood pressure during the treatment period (P > 0.05). Based on the data, exposure to low to moderate levels of ergot alkaloids during the stocker phase had a negative impact on hemodynamic responses and supplemental CP had minimal impact to alleviate symptoms. Therefore, feeding additional protein above established requirements is not expected to help alleviate fescue toxicosis.}, number={9}, journal={Journal of Animal Science}, publisher={Oxford University Press (OUP)}, author={Poole, Rebecca K and Womble, Carrisa M and Poore, Matthew H and Poole, Daniel H and Pickworth, Carrie L}, year={2019}, month={Jul}, pages={3776–3785} } @article{poole_brown_poore_pickworth_poole_2019, title={Effects of endophyte-infected tall fescue seed and protein supplementation on stocker steers: II. Adaptive and innate immune function}, volume={97}, ISSN={0021-8812 1525-3163}, url={http://dx.doi.org/10.1093/jas/skz250}, DOI={10.1093/jas/skz250}, abstractNote={AbstractFescue toxicosis is a multifaceted syndrome common in cattle grazing endophyte-infected tall fescue that affects performance; however, little information is available pertaining to its effects on immunity. Recently, it has been shown that supplemental CP can improve performance in weaned steers postvaccination. Thus, the objective of this study was to evaluate the effect of supplemental CP on innate and adaptive immune responses in stocker steers chronically exposed to ergovaline. Angus steers (n = 12 pens; 3 steers/pen) were stratified by weight and assigned to a 2 × 2 factorial arrangement to examine crude protein levels of supplement (14% or 18%) and ergovaline exposure (0 or 185 μg ergovaline/kg BW/d via ground endophyte-free (EF) or endophyte-infected (EI) tall fescue seed, respectively) on immune response. Consumption of low to moderate concentration of ergovaline from EI tall fescue seed was sufficient to induce mild symptoms associated with fescue toxicosis. Blood samples were collected at day 0, 42, and 56 to evaluate infectious bovine rhinotracheitis (IBR) and bovine viral diarrhea virus (BVDV) type 1b titers following vaccine challenge. Additionally, serum cytokine concentrations were evaluated using Quantibody Bovine Cytokine Arrays on day 0, 28, and 42. Data were analyzed using PROC MIXED of SAS with repeated measures. Regardless of treatment, no differences were observed in IBR and BVDV-1b seroconversion following vaccine challenge (P > 0.05). Regardless of crude protein concentration, EI steers had greater concentrations of proinflammatory cytokines (TNF-α, IFN-γ, IL-1α), chemokines (CCL2, CCL4, MIG), anti-inflammatory cytokines (IL-2, -13, -15, -21), and various growth factors (FGF-1, IGF-1, VEGF-A) when compared to EF steers (P < 0.05). Furthermore, VEGF-A and IGF-1 concentrations were greater in EI-14 steers on day 28 compared to EI-18, EF-14, and EF-18 steers (P < 0.05), however, this difference was not observed on day 0 or 42 (P > 0.05). Based on these data, steers exposed to ergovaline have an increase in pro- and anti-inflammatory cytokines and supplemental CP had minimal impact to mitigate this response. However, in the current study, exposure to ergovaline had little to no effect on adaptive immunity and response to vaccination. Together, chronic exposure to ergovaline results in a hyperactive innate immune response, which may lead to an immuno-compromised animal.}, number={10}, journal={Journal of Animal Science}, publisher={Oxford University Press (OUP)}, author={Poole, Rebecca K and Brown, Alecia R and Poore, Matthew H and Pickworth, Carrie L and Poole, Daniel H}, year={2019}, month={Jul}, pages={4160–4170} } @article{mayberry_poole_newsome_khanal_poore_serao_poole_2019, title={Evaluation of cytokine response as an indicator of genetic resistance to fescue toxicosis in purebred Angus cattle.}, volume={97}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz053.102}, abstractNote={Abstract Fescue toxicosis is a multifaceted syndrome common in cattle grazing endophyte-infected tall fescue. However, varying responses among cattle potentially implies genetic tolerance to the syndrome. Therefore, the objective was to evaluate the cytokine response of cows deemed either tolerant or susceptible to endophyte-infected fescue. Angus cows, 2–4 yrs old, grazed endophyte-infected tall fescue at two locations for 13 weeks starting mid-April 2016. A post-hoc analysis of animal performance was utilized to designate cattle into either tolerant (n = 20) or susceptible (n = 20) groups, based on physiological responses (changes in ADG) to chronic exposure to endophyte-infected fescue. Blood samples collected on weeks 1, 7, and 13 were used to evaluate serum prolactin (PRL) concentration. Cytokine concentrations were evaluated via Quantibody Bovine Cytokine Arrays. Data were analyzed using PROC MIXED of SAS with repeated measures. There were no differences by location or week. Tolerant cows tended to have decreased overall PRL concentrations compared to susceptible cows (98.3 and 138.4 ng/mL, respectively; P = 0.08). G protein-coupled receptor associated sorting protein (GASP)-1, a down-regulator of G protein-coupled receptors including D2-dopamine receptor a regulator of PRL secretion, was greater in tolerant cows when compared to susceptible cows (4.7 and 4.2 ng/mL; P = 0.03). Vascular endothelial growth factor (VEGF)-A was greater in tolerant cows when compared to susceptible cows (0.5 and 0.2 ng/mL; P = 0.02). Finally, interleukin (IL)-4, an anti-inflammatory cytokine, tended to be greater in tolerant cows when compared to susceptible cows (2.2 and 0.8 ng/mL, respectively; P = 0.07). Based on these data, greater concentrations of GASP-1, VEGF-A, and IL-4 in tolerant compared to susceptible cattle may mitigate the detrimental effects of fescue toxicosis, including suppressed PRL and vasoconstriction, leading to improved animal performance in a fescue environment. Additionally, these cytokines may serve as potential biomarkers for determining an animal’s tolerance or susceptibility to negative effects associated with endophyte-infected tall fescue}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Mayberry, Kyle and Poole, Rebecca K. and Newsome, McKayla A. and Khanal, Piush and Poore, Matthew H. and Serao, Nick V. L. and Poole, Daniel H.}, year={2019}, month={Jul}, pages={45–46} } @article{khanal_sanglard_mayberry_sommer_poore_poole_serao_2019, title={Genes and functions associated with tolerance to fescue toxicosis in Angus cows}, volume={97}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz122.295}, abstractNote={Abstract The objective of this study was to identify differentially expressed genes (DEG) and functions associated with tolerance to fescue toxicosis (FT). Forty pregnant purebred Angus cows were selected based on their growth at two locations in North Carolina (Butner Beef Cattle Field Laboratory, BBFCL; Upper Piedmont Research Station, UPRS) and classified as either high tolerant (HT) or low tolerant (LT) to FT with 20 cows in each group balanced by location. Blood samples were collected on weeks 1, 5, 9, and 13 for RNA sequencing. Counts were analyzed using a negative binomial model including the effects of genetic group, location, time, all possible interactions of these effects, flow cell, covariate of RNA integrity number, and normalized library size as offset. Genotype-by-location-by-time interaction was evident with a high number (4,453) of DEG (q-value<0.1) between genetic groups on week 5 at UPRS compared to all other possible interactions. So further analyses were focused on week 5 at UPRS. The most significant upregulated genes in LT and HT animals were ENPP6 and MESP2, respectively, with log2 fold changes of 1.90 [95% confidence interval = 0.89, 2.92] q-value=0.005) and 0.91 [0.35, 1.47] (q-value=0.01), respectively. Other top 5 upregulated genes for HT animals were CTBS, CLDN19, SPDYC, HEYL, and SDC2, and for LT animals were OLIG1, IL13, ANXA13, ENSBTAG00000024188and CXCL13. Enrichment analysis (P < 0.05) showed that DEG between genetic groups have general functions, such as metabolic, biosynthetic, and catabolic processes, as well as DNA and RNA-related functions, such as translation, transcription, and repair. These findings helped characterizing the genetic basis of tolerance to FT in cattle. In addition, we identified genes that may serve as potential biomarkers for tolerance to FT}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Khanal, Piush and Sanglard, Leticia Pereira and Mayberry, Kyle and Sommer, Jeffrey and Poore, Matthew H. and Poole, Daniel H. and Serao, Nick V. L.}, year={2019}, month={Jul}, pages={167–167} } @misc{poole_poole_2019, title={Impact of Ergot Alkaloids on Female Reproduction in Domestic Livestock Species}, volume={11}, ISSN={["2072-6651"]}, DOI={10.3390/toxins11060364}, abstractNote={Fescue toxicosis is a multifaceted syndrome that elicits many negative effects on livestock consuming ergot alkaloids produced by endophyte-infected tall fescue. The economic losses associated with fescue toxicosis are primarily due to reproductive failure including altered cyclicity, suppressed hormone secretion, reduced pregnancy rates, agalactia, and reduced offspring birth weights. For decades, a multitude of research has investigated the physiological and cellular mechanisms of these reproductive failures associated with fescue toxicosis. This review will summarize the various effects of ergot alkaloids on female reproduction in grazing livestock species.}, number={6}, journal={TOXINS}, author={Poole, Rebecca K. and Poole, Daniel H.}, year={2019}, month={Jun} } @article{poole_devine_mayberry_eisemann_poore_long_poole_2019, title={Impact of slick hair trait on physiological and reproductive performance in beef heifers consuming ergot alkaloids from endophyte-infected tall fescue}, volume={97}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz024}, abstractNote={Fescue toxicosis is a multifaceted syndrome common in cattle grazing endophyte-infected tall fescue. The objective of this study was to evaluate the impact of the slick hair trait on physiological and reproductive parameters in heifers experiencing fescue toxicosis. Angus × Senepol heifers (n = 31) were blocked by weight (393.5 ± 17.3 kg) and phenotype relative to hair coat at birth, and randomly fed novel endophyte fescue (EN) or endophyte-infected fescue (EI) haylage in a total mixed ration for 91 d. Weekly measurements were collected to monitor heifer growth and response during ergot alkaloids exposure. Following 28 d of treatment, estrus was synchronized and heifers were inseminated. Ovary mapping and AI pregnancy rate were examined via transrectal ultrasonography. Blood samples were taken for genotyping: slick (S) or wildtype (W). Data were analyzed using repeated measures in PROC MIXED of SAS including fescue treatment (EN vs. EI), genotype (S vs. W), and sample collection time as main effects. Body condition scores were decreased for W heifers compared with S heifers (5.48 vs. 5.66, respectively; P < 0.0001). Surface temperature was greater for EI-W heifers (37.2 °C) compared with other groups (36.4, 36.6, 36.7 °C for EN-S, EN-W, EI-S, respectively; P < 0.05). Serum PRL concentrations were reduced for EI heifers compared with EN heifers (133.5 vs. 163.1 ng/mL, respectively; P < 0.05). The average number of 2 to 4 mm follicles were greater in EI-W heifers (13.8 follicles) compared with other groups (12.2, 10.6, and 11.1 for EN-S, EN-W, and EI-S, respectively; P < 0.0001). However, the average number of preovulatory follicles (≥9 mm) were reduced in EI-W heifers (0.52 follicles) compared with other heifer groups (0.94, 0.88, and 0.85 ± 0.04 for EN-S, EN-W, and EI-S, respectively; P < 0.05). Ovulatory follicle size was smaller in EI-W heifers compared with EN-W heifers (9.14 vs. 11.57 mm, respectively; P = 0.05). Corpus luteum area was reduced in EI-W heifers (235.1 mm2) compared with other heifer groups (297.2, 272.7, and 276.8 mm2 for EN-S, EN-W, and EI-S, respectively; P < 0.05). Concentrations of P4 were greater for EN heifers compared with EI heifers (2.7 vs. 1.8 ng/mL, respectively; P < 0.05). Pregnancy was not established in EI-W heifers (0%) compared with other heifer groups (37.5%, 57.1%, and 62.5% for EN-S, EN-W, and EI-S, respectively; P < 0.05). Overall, the slick hair mutation appears to aid in offsetting the physiological symptoms associated with fescue toxicosis and helps to improve reproductive performance.}, number={4}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Poole, Rebecca K. and Devine, Thomas L. and Mayberry, Kyle J. and Eisemann, Joan H. and Poore, Matt H. and Long, Nathan M. and Poole, Daniel H.}, year={2019}, month={Apr}, pages={1456–1467} } @article{davis_poole_poore_poole_pickworth_2019, title={Interaction of dietary protein and endophyte-infected Tall Fescue seed in stocker steers on finishing phase performance and carcass traits.}, volume={97}, ISBN={1525-3163}, DOI={10.1093/jas/skz053.086}, abstractNote={Abstract Fescue toxicosis is a multifaceted disease that negatively impacts cattle. It was hypothesized that exposure to endophyte-infected fescue during the stocker phase affects finishing phase growth and carcass characteristics. Eight-month-old steers were sorted by weight and randomly assigned to receive one of four treatments for 56 days in confinement: endophyte-free seed (0 ug/ kg ergovaline) with either 18% (EF-18; n = 9) or 14% dietary protein (EF-14; n = 9) and endophyte-infected seed (500 ug/kg ergovaline) with 18% (EI-18; n = 9) or 14% dietary protein (EI-14; n = 9). Following fescue exposure calves were backgrounded on novel endophyte fescue pastures for 8 mo. At 18 mo, all steers were vaccinated, implanted, and reentered the feedlot for a 112 d growing phase and 52 d finishing phase. Body weight was recorded every 28 d and carcass data was collected at slaughter. Data were analyzed using the MIXED procedure of SAS for effects of BW, ADG, dressing percentage (DP), HCW, backfat, ribeye area (REA), KPH, USDA Yield grade (YG), and USDA Quality grade (QG). Statistical significance was determined at P > 0.05) HCW, BW, backfat, REA, DP, or QG. TheEI-14 had a greater ADG (1.69 kg/d) during the feedlot growing phase compared to the other treatment groups (1.53, 1.47, 1.55 for EI-18, EF-14, EF-18, respectively; P > 0.05). Steers stockered on 18% dietary protein had greater BW compared to steers previously fed at 14% (501.3±3.8 vs. 489.7±3.8; P = 0.0339). In addition, 18% protein in stocker diet resulted in greater KPH (2.3±0.2 vs. 1.78±0.2; P = 0.0129) and YG (3.4±0.1 vs. 3.0±0.1; P = 0.0168) compared with steers fed 14% dietary protein. Finishing growth and carcass characteristics were not affected by exposure to ergot alkaloids at weaning as much as dietary protein when cattle had a background period prior to feedlot entry}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Davis, Matthew E. and Poole, Rebecca K. and Poore, Matthew H. and Poole, Daniel H. and Pickworth, Carrie L.}, year={2019}, month={Jul}, pages={38–38} } @article{jackson_newsome_brown_poole_dudley_poore_poole_2019, title={Long term impact of ergot alkaloids on fetal heifer development and subsequent growth and reproductive performance.}, volume={97}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz053.103}, abstractNote={Abstract Previous studies from our laboratory have demonstrated physiological differences in mid-gestation cows grazing either endophyte-infected (EI) or endophyte-free (EF) tall fescue. The objective of this study was to investigate the effects of in utero exposure (TRT) of either EI or EF on heifer growth, reproductive tract development and onset of puberty. Pregnant Angus and SimAngus cows were blocked by age, BW, and breed; and then randomly assigned to graze either EF (n = 27) or EI (n = 27) pastures. At parturition, heifer birthweight was recorded and placental tissues were collected to assess placental characteristics. Heifer BW, height, frame score were recorded at weaning. Assessment of puberty via measurement of BW, BCS, reproductive tract scores (RTS) and pelvic area (PA) started at 10 mo of age. Data were analyzed using a MIXED procedure of SAS and examined for effects of TRT, sire, and age. Statistical significance was determined at P < 0.05 and a tendency at 0.05); however, there was a sire by treatment interaction for ADG during onset of puberty (P < 0.05). While TRT did not affect PA or RTS (P > 0.05) at 10 mo of age, sire significantly influenced RTS (P < 0.05) thus impacting of onset of puberty. While consumption of EI fescue impacts cow performance, calf birthweight, and ratio of cotyledon to placenta weight, it has minimal effect on postnatal growth and development through 10 mo of age. Further studies are needed to determine the impact on heifer reproductive performance.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Jackson, McKenzie Lane and Newsome, McKayla A. and Brown, Alecia R. and Poole, Rebecca K. and Dudley, Harrison B. and Poore, Matthew H. and Poole, Daniel H.}, year={2019}, month={Jul}, pages={46–46} } @article{ingram_poore_poole_2019, title={Renovating toxic-infected tall fescue pastures for profitability, animal performance, and soil health.}, volume={97}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz053.084}, abstractNote={Abstract Renovating toxic-infected tall fescue (TF) pastures to non-toxic infected tall fescue (NE) for profitability, animal and agronomic performance without compromising soil health is needed to transition to NE in the southeast U.S. Three renovation strategies were evaluated for impact on soil health, profitability, and animal and agronomic performance in a replicated field trial located in Bahama, NC. Strategies included: 1) control (C), 2) renovation to NE after one season of a single specie cover crop (1-SM), 3) renovation to NE after three seasons of a single specie cover crop (3-SM), and 4) renovation to NE after three seasons of a multi-specie cover crop (3-CM). Soil samples were taken prior to renovation to establish baseline soil health measurements for each strategy. Data were analyzed using proc GLM of SAS v9.4. Thirty-two Angus and Angus cross steers (initial BW 425 ± 27) were blocked by BW and randomly assigned to one of four treatments during the first season of renovation. Average daily gain for cattle grazing the first season of cover crops was greatest (P < 0.001) with 3-CM (0.8 kg/d), 3-SM (0.8 kg/d), in comparison to C and 1-SM (-0.1 kg/d). Gain per hectare differed among treatments (P < 0.001) with 3-SM and 3-CM being greater than C and 1-SM (179, 154, -24, -43 kg/ha, respectively). Within the two-month grazing period, yield different during the month of August (P < 0.001), with 3-SM being the highest (4511 kg/ha) in comparison to 3-CM (3275 kg/ha), 1-SM (2922 kg/ha), and C (2644 kg/ha), while yield was highest (P < 0.001) for 3-CM in September (2931 kg/ha) in comparison to all other treatments. Data suggests agronomic and animal performance for 3-CM and 3-SM were improved compared to C and could partially alleviate initial renovation costs.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Ingram, Sam and Poore, Matthew H. and Poole, Daniel H.}, year={2019}, month={Jul}, pages={37–38} } @article{ingram_poore_poole_2019, title={Renovating toxic-infected tall fescue pastures for profitability, animal performance, and soil health.}, volume={97}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz053.044}, abstractNote={Abstract Renovating toxic-infected tall fescue (TF) pastures to non-toxic infected tall fescue (NE) for profitability, animal and agronomic performance without compromising soil health is needed to transition to NE in the southeast U.S. Three renovation strategies were evaluated for impact on soil health, profitability, and animal and agronomic performance in a replicated field trial located in Bahama, NC. Strategies included: 1) control (C), 2) renovation to NE after one season of a single specie cover crop (1-SM), 3) renovation to NE after three seasons of a single specie cover crop (3-SM), and 4) renovation to NE after three seasons of a multi-specie cover crop (3-CM). Soil samples were taken prior to renovation to establish baseline soil health measurements for each strategy. Data were analyzed using proc GLM of SAS v9.4. Thirty-two Angus and Angus cross steers (initial BW 425 ± 27) were blocked by BW and randomly assigned to one of four treatments during the first season of renovation. Average daily gain for cattle grazing the first season of cover crops was greatest (P < 0.001) with 3-CM (0.8 kg/d), 3-SM (0.8 kg/d), in comparison to C and 1-SM (-0.1 kg/d). Gain per hectare differed among treatments (P < 0.001) with 3-SM and 3-CM being greater than C and 1-SM (179, 154, -24, -43 kg/ha, respectively). Within the two-month grazing period, yield different during the month of August (P < 0.001), with 3-SM being the highest (4511 kg/ha) in comparison to 3-CM (3275 kg/ha), 1-SM (2922 kg/ha), and C (2644 kg/ha), while yield was highest (P <0.001) for 3-CM in September (2931 kg/ha) in comparison to all other treatments. Data suggest agronomic and animal performance for 3-CM and 3-SM were improved compared to C and could partially alleviate initial renovation costs.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Ingram, Sam and Poore, Matthew H. and Poole, Daniel H.}, year={2019}, month={Jul}, pages={20–20} } @article{smith_poole_mayberry_newsome_dudley_poole_2019, title={Timing of progesterone exposure effects pregnancy rates following fixed time artificial insemination in postpartum beef cows.}, volume={97}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz053.098}, abstractNote={Abstract Advancements in reproductive technologies have improved pregnancy rates in postpartum cows; however, undesirable consequences leading to reduced fertility still occur. Thus, the objectives were to determine if presence of a corpus luteum (CL) at the start of estrous synchronization (AIM1) or if the length of proestrus (interval from progesterone removal to a GnRH-induced LH surge; AIM2) alters fixed timed artificial insemination (FTAI) pregnancy rates. Cycling postpartum cows (n = 285) at two locations were synchronized using the CO-Synch+CIDR® FTAI protocol. Ultrasonographic measurements of luteal area were recorded at CIDR insertion. To determine the impact of proestrus length, cows were randomly assigned to either undergo CIDR removal at the time of PGF2a injection (long proestrus, n = 145), or CIDR removal 24 hours post PGF2a injection (short proestrus, n = 140). Blood samples were collected at CIDR insertion and at insemination for progesterone (P4) analysis. Pregnancy status to FTAI was assessed using ultrasonographic diagnosis at 30 d post insemination. Data were analyzed using a MIXED procedure of SAS and examined for effects of length of proestrus, P4 concentration, luteal area, sire, location, and age. Statistical significance was determined at P0.05) pregnancy rates. Pregnancy rates were greater in cows with >1 ng/mL P4 compared to cows with 0.05). Cows > 4 y old had higher AI pregnancy rates compared to 2–3 y cows (70.2±7.4 vs. 51±5.8%, respectively; P > 0.05). Based on these data, incorporating a presynchronization program to ensure the presence of a functional CL at the start of a FTAI protocol may improve pregnancy success in postpartum beef cows.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Smith, Anna L. and Poole, Rebecca K. and Mayberry, Kyle and Newsome, McKayla A. and Dudley, Harrison B. and Poole, Daniel H.}, year={2019}, month={Jul}, pages={43–44} } @article{smith_poole_mayberry_newsome_dudley_poole_2019, title={Timing of progesterone exposure effects pregnancy rates following fixed timed artificial insemination in postpartum beef cows.}, volume={97}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skz053.195}, abstractNote={Abstract Advancements in reproductive technologies have improved pregnancy rates in postpartum cows; however, undesirable consequences leading to reduced fertility still occur. Thus, the objectives were to determine if presence of a corpus luteum (CL) at the start of estrous synchronization (AIM1) or if the length of proestrus (interval from progesterone removal to a GnRH-induced LH surge; AIM2) alters fixed timed artificial insemination (FTAI) pregnancy rates. Cycling postpartum cows (n = 285) at two locations were synchronized using the CO-Synch+CIDR® FTAI protocol. Ultrasonographic measurements of luteal area were recorded at CIDR insertion. To determine the impact of proestrus length, cows were randomly assigned to either undergo CIDR removal at the time of PGF2a injection (long proestrus, n = 145), or CIDR removal 24 hours post PGF2a injection (short proestrus, n = 140). Blood samples were collected at CIDR insertion and at insemination for progesterone (P4) analysis. Pregnancy status to FTAI was assessed using ultrasonographic diagnosis at 30 d post insemination. Data were analyzed using a MIXED procedure of SAS and examined for effects of length of proestrus, P4 concentration, luteal area, sire, location, and age. Statistical significance was determined at P 0.05) pregnancy rates. Pregnancy rates were greater in cows with >1 ng/mL P4 compared to cows with 0.05). Cows > 4 y old had higher AI pregnancy rates compared to 2–3 y cows (70.2±7.4 vs. 51±5.8%, respectively; P > 0.05). Based on these data, incorporating a presynchronization program to ensure the presence of a functional CL at the start of a FTAI protocol may improve pregnancy success in postpartum beef cows.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Smith, Anna L. and Poole, Rebecca K. and Mayberry, Kyle and Newsome, McKayla A. and Dudley, Harrison B. and Poole, Daniel H.}, year={2019}, month={Jul}, pages={85–85} } @article{womble_poole_poole_pickworth_2018, title={142 Impact of Protein Supplementation on Physiological Response of Steers Consuming Endophyte-Infected Tall Fescue Seed.}, volume={96}, ISSN={0021-8812 1525-3163}, url={http://dx.doi.org/10.1093/jas/sky027.142}, DOI={10.1093/jas/sky027.142}, abstractNote={Fescue toxicosis in beef cattle is caused by consumption of ergot alkaloids produced by endophyte-infected tall fescue and results in chronic decreases in productivity and growth performance. It was hypothesized that protein supplementation may have a positive effect on the physiological responses of growing steers consuming ergot alkaloids. In this study, 36 weaned steers (196.1 ± 3.6 kg) were used in a 2 x 2 factorial arrangement of treatments to evaluate physiological responses to chronic exposure to ergot alkaloids via fescue seed and dietary protein. Steers were blocked by weight and randomly assigned to one of four treatment groups for 56 d: endophyte-free seed diet (0 ppm ergovaline) with 14% CP (EF-14), endophyte-free seed diet with 18% CP (EF-18), endophyte-infected seed diet (500 ppm ergovaline) with 14% CP (EI-14), and endophyte-infected seed diet with 18% CP (EI-18). Steers were fed at a calculated rate of 2.35% BW to achieve similar intake among treatment groups. Weekly physiological measurements were collected to evaluate the steers’ responses to the diets. On d 14, iButton temperature data loggers were subcutaneously inserted in the lateral neck region to record hourly body temperature. Steers received the bovine viral diarrhea types 1 and 2 and infectious bovine rhinotracheitis vaccines on d 28, then were administered booster vaccines on d 42. Data were analyzed using the MIXED procedure in SAS with repeated measures. Statistical significance was determined at P < 0.05 and a tendency at 0.05 < P < 0.10. The DMI expressed as % BW and kg per day was uniform across treatments. No differences were observed in BCS, BW, and ADG among treatment groups. However, the EI-14 steers had a less efficient F:G ratio compared to other treatment groups (6.18, 5.6, 5.7, 5.5 for EI-14, EI-18, EF-14, EF-18, respectively; P < 0.05). In contrast to previous studies, hair coat score and hair coat shedding score were not different among treatment groups (P > 0.05). The EI-18 steers had a lower heart rate compared to other groups (88.0, 98.0, 93.2, 94.8 beats per minute for EI-18, EI-14, EF-14, EF-18, respectively; P < 0.05). Meanwhile, EI steers had higher rectal temperatures and respiratory rates starting on d 35 of the feeding period compared to EF steers (P < 0.05). Diurnal rhythms in subcutaneous body temperatures varied among treatment groups throughout the feeding period (P < 0.05). Overall, physiological responses to fescue toxicosis were minimal in the growing steers.}, number={suppl_1}, journal={Journal of Animal Science}, publisher={Oxford University Press (OUP)}, author={Womble, C M and Poole, R K and Poole, D H and Pickworth, C L}, year={2018}, month={Mar}, pages={75–76} } @article{poole_womble_pickworth_poole_2018, title={41 “Effect of Protein Supplementation on Immune Response of Weaned Steers Consuming Endophyte-Infected Tall Fescue Seed”.}, volume={96}, ISSN={0021-8812 1525-3163}, url={http://dx.doi.org/10.1093/jas/sky027.041}, DOI={10.1093/jas/sky027.041}, abstractNote={Fescue toxicosis is a multifaceted disease that negatively impacts growth and performance. Cattle grazing endophyte-infected fescue have a depressed immune response to vaccinations. Therefore, the goal of this study was to evaluate the impact of protein supplementation on weaned calves’ physiological and immune responses while consuming an ergot alkaloid toxin (i.e. ergovaline) commonly produced by endophyte-infected tall fescue. Thirty-six naïve beef steers (196.1 ± 3.6 kg) were blocked by weight and randomly assigned to receive one of four treatments in a total mixed ration (TMR): endophyte-free seed (0 ppm ergovaline) and 18% protein supplementation (EF-18; n=9), endophyte-free seed and 14% supplementation (EF-14; n=9), endophyte-infected seed (500 ppm ergovaline) and 18% supplementation (EI-18; n=9), and endophyte-infected seed and 14% supplementation (EI-14; n=9). Diameter of caudal artery and vein were recorded weekly by ultrasound. On d14 of the feeding trial, iButton® temperature data loggers were inserted in the lateral neck region to hourly record the subcutaneous body temperature. On d28, steers were vaccinated against infectious bovine rhinotracheitis (IBR) and bovine viral diarrhea (BVD) types 1 and 2 viruses. Steers received a booster two weeks later (d42). Blood samples were collected at d0, 42, and 56 to evaluate titers to IBR and BVDV1b. Data were analyzed using PROC MIXED of SAS with repeated measures. A treatment interaction was observed with EI-14 steers experiencing vasodilation of the caudal artery (27.4 mm2) in comparison to other steer groups (P<0.05; 26.8, 26.1, 25.8 ± 0.5 mm2 for EF-18, EF-14, and EI-18, respectively). A similar effect of greater caudal vein diameters was observed in EI-14 steers (35.0 mm2) when compared to other steer groups (P<0.05; 33.6, 32.8, 32.0 ± 0.6 mm2 for EF-18, EF-14, and EI-18, respectively). Subcutaneous body temperature was higher in EI-14 steers compared to EF-14 steers after the vaccination (P<0.05; 38.0 and 37.7 ± 0.1 °C, respectively) and booster (P<0.05; 37.9 and 37.6 ± 0.1 °C, respectively). A tendency was observed in the seroconversion of IBR and BVDV1b antibody titers with a greater seroconversion in EI-18 steers compared to EF-18 steers (P=0.09; 66.7 and 44.4 ± 9.2% for IBR and P=0.08, 66.7 and 48.2 ± 7.5% for BVDV1b, respectively), no differences were observed when compared to other steer groups. Overall, a unique response was observed in steers consuming ergovaline as a result of protein supplementation, with 14% protein effecting blood flow and 18% protein having a potential impact on the animal’s immune response.}, number={suppl_1}, journal={Journal of Animal Science}, publisher={Oxford University Press (OUP)}, author={Poole, R K and Womble, C M and Pickworth, C L and Poole, D H}, year={2018}, month={Mar}, pages={21–22} } @article{monn_poole_mackey_mayberry_dudley_alley_poole_2019, title={A two-injection prostaglandin F-2 alpha presynchronization treatment decreases pregnancy rates of cycling replacement beef heifers}, volume={3}, ISSN={["2573-2102"]}, DOI={10.1093/tas/txy136}, abstractNote={Abstract Improving artificial insemination (AI) pregnancy rates in replacement heifers improves the genetic advancement within a herd. Heifers that have completed at least three estrous cycles prior to breeding have greater pregnancy rates compared to acyclic females. Therefore, it was hypothesized that a presynchronization treatment program consisting of two injections of prostaglandin F2α (PGF2α) prior to the start of the CO-Synch + 5 d CIDR protocol would initiate earlier attainment of puberty and more estrous cycles prior to AI, thus increasing AI pregnancy rates. All heifers were managed the same at two locations over the course of 2 yr. Heifers were randomly assigned to receive either the two-injection PGF2α presynchronization treatment (PreSynch; n = 105) or no presynchronization (Control; n = 106) prior to the start of estrous synchronization. On the first day of the trial, reproductive tract scores (RTSs), pelvic areas, body condition scores, and weights were collected on all heifers. All heifers were synchronized with the CO-Synch + 5 d CIDR protocol and fixed-time artificially inseminated with semen from a bull of known fertility. Blood samples were collected three consecutive times at 7 d intervals starting 45 d prior to estrous synchronization to determine the onset of puberty via analyzing progesterone concentrations. Pregnancy status to AI was assessed using ultrasonography diagnosis at approximately 30 and 60 d post insemination. Data were analyzed using PROC MIXED of SAS and reported as least square mean. The PreSynch treatment decreased AI pregnancy rates (52.2% vs. 38.1 ± 6.3% for Control vs. PreSynch, respectively; P = 0.06) and did not result in earlier attainment of puberty in beef heifers (P > 0.05). The PreSynch treatment did not impact pregnancy rates in heifers with an RTS of 3 or 4 (P > 0.05). However, PreSynch heifers with an RTS of 5 had decreased pregnancy rates (68.3% vs. 46.9 ± 10.1% for Control vs. PreSynch, respectively; P < 0.05). Finally, PreSynch heifers with increased body condition of 6 had decreased pregnancy rates when compared to Control heifers (37.5% vs. 62.5 ± 11.6%, respectively; P < 0.05). On the basis of these data, implementation of heifer breeding soundness examination at least 3 wk prior to the start of the breeding season may be beneficial for selecting replacement females; however, presynchronization with prostaglandins immediately prior to estrous synchronization will negatively affect AI pregnancy rates in cycling pubertal heifers.}, number={1}, journal={TRANSLATIONAL ANIMAL SCIENCE}, author={Monn, Ruby E. and Poole, Rebecca K. and Mackey, J. Christopher and Mayberry, Kyle J. and Dudley, Harrison B. and Alley, Mark and Poole, Daniel H.}, year={2019}, month={Jan}, pages={456–463} } @article{poole_lyons_poole_poore_2018, title={Ergot alkaloids induce vasoconstriction of bovine uterine and ovarian blood vessels}, volume={96}, ISSN={["1525-3163"]}, DOI={10.1093/jas/sky328}, abstractNote={Fescue toxicosis is a syndrome that impairs growth and reproduction in cattle grazing endophyte-infected tall fescue [Lolium arundinaceum [(Schreb.].) Darbysh)] in the United States, resulting in approximately $1 billion in annual economic loss in species that utilize this forage resource. Approximately 90% of tall fescue contains an endophytic fungus (Epichloë coenophiala) that produces ergot alkaloids. Ergot alkaloids cause vasoconstriction and reduced blood flow to the extremities; however, it remains unknown how blood flow to the reproductive organs is affected in cattle. Therefore, the objective of this study was to determine if ergot alkaloids from endophyte-infected tall fescue reduce blood flow to the reproductive organs, thus hindering reproductive function. Angus heifers (n = 36) naïve to ergot alkaloids were placed in Calan gates and randomly assigned to receive either endophyte-infected fescue seed (E+) or noninfected fescue seed (E-; control) in a total mixed ration for 63 d. Weekly measurements were taken to monitor heifer growth and response to ergot alkaloid exposure. Reproductive measurements, including ovarian structures, uterine and ovarian vessel diameter, and hormone concentrations were determined after heifers were synchronized using the standard CO-Synch + 7 d CIDR protocol to ensure all measurements were collected at the same stages of the estrous cycle (0, 4, 10, and 17 d). Data were analyzed using repeated measures in PROC MIXED of SAS. Average daily gain was decreased for the E+ group (0.8 kg/d) compared to control heifers (1.0 kg/d). Body condition scores tended to be greater in control heifers compared to the E+ group (P = 0.053). Additionally, hair coat and hair shedding scores were greater in E+ heifers compared to controls (P < 0.05). Heart rate, rectal temperature, respiration rate, and blood pressure did not differ between treatments (P > 0.05). Vasoconstriction was observed in the caudal artery, but not the caudal vein, in heifers consuming the E+ fescue seed (P < 0.05). No differences were observed in antral follicle counts, corpus luteum area or circulating progesterone concentrations in E+ heifers compared to controls (P > 0.05). There was a significant decrease in the diameter of arteries and veins servicing the ovary and uterus on day 10 and 17 of the estrous cycle. Reduction in blood flow to the reproductive organs during critical times in the estrous cycle may contribute to the reduced ovarian function and pregnancy rates associated with fescue toxicosis.}, number={11}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Poole, Daniel H. and Lyons, Sarah E. and Poole, Rebecca K. and Poore, Matt H.}, year={2018}, month={Nov}, pages={4812–4822} } @article{mayberry_khanal_poore_serao_poole_2018, title={Evaluation of Angus Calf Performance Based on Dams Tolerance or Susceptibility to Fescue Toxicosis.}, volume={96}, ISSN={["1525-3163"]}, DOI={10.1093/jas/sky027.103}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Mayberry, K. and Khanal, P. and Poore, M. H. and Serao, N. V. L. and Poole, D. H.}, year={2018}, month={Mar}, pages={55–55} } @article{newsome_monn_mayberry_poole_young_poore_poole_2018, title={Grazing Novel or Endophyte-Infected Tall Fescue during Mid-Gestation Impacts Cow Performance.}, volume={96}, ISSN={["1525-3163"]}, DOI={10.1093/jas/sky027.025}, abstractNote={Consumption of endophyte-infected tall fescue results in poor reproductive performance. The objective of this study was to examine physiological changes in pregnant cows grazing tall fescue to develop a better understanding of the factors that contribute to the poor reproductive performance attributed to fescue toxicosis. Pregnant Angus and Simmental-Angus cows were blocked by age (2–3, 4–7, and >7 y), BW, and breed; and then randomly assigned to graze either novel (E-; <5% infection rate; n=27) or endophyte-infected tall fescue (E+; 79.5% infection rate; n=27). Weekly BW, BCS, hair coat scores (HCS), and hair shedding scores (HSS) were collected from mid-April through July when ergot alkaloid concentrations are greatest in the forage. Blood samples were collected to measure progesterone concentrations. Forage samples were taken every 2 wks to determine forage quality and composition. Data were analyzed using the MIXED procedure of SAS with repeated measures examined for effects of age, treatment (E- or E+) and time. Statistical significance was determined at P<0.05 and a tendency at 0.05
7 y) cows having higher scores when compared to younger cows (6.0, 6.1, and 5.7, respectively; P<0.05). The HCS and HSS were greater in cows on E+ pastures compared to cows on E- pastures (P<0.05). The HSS were greater in the >7 y cows (2.69) compared to other age groups (2.40, 2.51, for 2–3 and 4–7 y, respectively, P<0.05) on E+ pastures, whereas no age differences in HCS were observed in cows on E- pastures. By d21 of the grazing period, cows on E- pastures displayed a greater ability to shed hair compared to cattle on E+ pastures (P<0.0001), which continued throughout the remainder of the grazing period. Progesterone concentrations in E+ cows (3.75 ng/ml) were decreased throughout the grazing period compared to E- cows (6.53 ng/mL, P<0.05). The impact of reduced progesterone concentrations, greater HCS and HSS and tendency for decreased ADG in cows grazing E+ during mid-gestation, compared to cows grazing E-, on calf development remains unknown.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Newsome, M. A. and Monn, R. E. and Mayberry, K. and Poole, R. K. and Young, Z. and Poore, M. H. and Poole, D. H.}, year={2018}, month={Mar}, pages={13–13} }
@article{monn_shea_mayberry_freeman_poole_poore_2018, title={Implementing Shade and Slick Hair Phenotypes Improves Heifer Performance}, volume={96}, ISSN={["1525-3163"]}, DOI={10.1093/jas/sky027.150}, abstractNote={Studies have shown that proper regulation of body temperature is essential for optimum productivity in cattle. The objective of this pilot study was to determine if the shade provided by silvopasture or incorporation of the slick hair phenotype improves beef heifer performance. Senepol cross beef heifers (n=12) were blocked by hair coat phenotype, either slick or normal, and randomly assigned to graze shaded or non-shaded pastures from May through October. During this grazing period, BCS, hair coat scores (HCS), hair shedding scores (HSS) and fly counts were recorded every 2 wk. Additionally, heifers were weighed at the beginning and end of the grazing period to determine ADG. On d 112 of the grazing period, iButton® temperature data loggers were attached to CIDR-blanks to record vaginal body temperature every 15 min for 14 d. Data were analyzed using the MIXED procedure of SAS with repeated measures examined for effects of hair coat phenotype, pasture (shaded or non-shaded) and time on ADG, HSS, HCS, fly count, and body temperature. Statistical significance was determined at P < 0.05. HCS, but not HSS, were greater in the normal hair phenotype heifers compared to heifers with the slick phenotype. Incorporation of shade lowered HCS of normal hair coat heifers, but not heifers with the slick hair phenotype (P < 0.05). Heifers with the slick hair phenotype in non-shaded pastures had decreased HSS compared to heifers with the normal hair phenotype (P < 0.05). A greater ADG was observed in heifers with the slick phenotype compared to normal hair phenotype (0.46 and 0.36 Kg/d, respectively; P < 0.05) as well as those cattle that were permitted shade compared to those without shade (0.48 and 0.33 Kg/d, respectively; P < 0.05). Fly counts were greatest in normal haired cattle (101.5 ± 27.6) in non-shaded pastures compared to the other animal groups (62.1,64.9, and 51.2 for slick in non-shaded, normal and slick in shaded pastures, respectively; P < 0.05). Heifers grazing in non-shaded pastures displayed a greater body temperature compared to those cattle permitted access to shade (P < 0.05). The combination of greater body temperatures, fly counts, HCS and HSS during the grazing period negatively impacted the growth performance of heifers in non-shaded pastures with the normal hair phenotype compared to the other animal groups.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Monn, R. E. and Shea, T. P. and Mayberry, K. and Freeman, S. R. and Poole, D. H. and Poore, M. H.}, year={2018}, month={Mar}, pages={79–80} }
@article{gadsby_nipper_faircloth_m. d'annibale-tolhurst_chang_farin_sheldon_poole_2017, title={Toll-like receptor and related cytokine mRNA expression in bovine corpora lutea during the oestrous cycle and pregnancy}, volume={52}, ISSN={["1439-0531"]}, DOI={10.1111/rda.12940}, abstractNote={ContentsImproving our understanding of the mechanisms controlling the corpus luteum (CL) and its role in regulating the reproductive cycle should lead to improvements in the sustainability of today's global animal industry. The corpus luteum (CL) is a transient endocrine organ composed of a heterogeneous mixture steroidogenic, endothelial and immune cells, and it is becoming clear that immune mechanisms play a key role in CL regulation especially in luteolysis. Toll‐like receptors (TLR) mediate innate immune mechanisms via the production of pro‐inflammatory cytokines, especially within various tissues, although the role of TLR within CL remains unknown. Thus, the objectives of this study were to characterize TLR mRNA expression in the CL during the oestrous cycle and in pregnancy (day 30–50), and to examine the role of TLR signalling in luteal cells. Corpora lutea were collected at various stages of the cycle and pregnancy and analysed for TLR and cytokine mRNA expression. In addition, luteal cells were cultured with the TLR4 ligand (lipopolysaccharide, LPS) for 24 h to evaluate the role of TLR4 in regulating luteal function. Toll‐like receptors 1, 2, 4, 6, tumour necrosis factor alpha (TNF), interferon gamma (IFN‐G), and interleukin (IL)‐12, mRNA expressions were greatest in regressing CL compared with earlier stages (p < .05), whereas no change was observed for IL‐6 mRNA expression. Cytokine mRNA expression in cultured luteal cells was not altered by LPS. Based on these data, one or more of the TLRs found within the CL may play a role in luteolysis, perhaps via pro‐inflammatory cytokine mRNA expression.}, number={3}, journal={REPRODUCTION IN DOMESTIC ANIMALS}, author={Gadsby, J. E. and Nipper, A. M. Tyson and Faircloth, H. A. and M. D'Annibale-Tolhurst and Chang, J. and Farin, P. W. and Sheldon, I. M. and Poole, D. H.}, year={2017}, month={Jun}, pages={495–504} }
@article{poole_ocon-grove_johnson_2016, title={Anti-Mullerian hormone (AMH) receptor type II expression and AMH activity in bovine granulosa cells}, volume={86}, ISSN={["1879-3231"]}, DOI={10.1016/j.theriogenology.2016.04.078}, abstractNote={Anti-Müllerian hormone (AMH) produced by granulosa cells has previously been proposed to play a role in regulating granulosa cell differentiation and follicle selection. Although AMH receptor type II (AMHR2) dimerizes with a type I receptor to initiate AMH signaling, little is known about the regulation of AMHR2 expression in bovine granulosa cells and the role of AMH in follicle development. The primary objectives of this study were to: (1) characterize AMHR2 expression in granulosa cells during follicle development; (2) identify factors that regulate AMHR2 mRNA expression in granulosa cells; and (3) examine the role of AMH signaling in granulosa cell differentiation and proliferation. Bovine granulosa cells were isolated from 5- to 8-mm follicles before selection and deviation, as well as from 9- to 12-mm and 13- to 24-mm follicles after selection. Analyses revealed that expression of AMHR2 was greater in 5- to 8-mm follicles compared with 13- to 24-mm follicles (P < 0.05). Granulosa cells treated with bone morphogenetic protein 6 (BMP6) or BMP15, but not BMP2, significantly increased AMHR2 expression when compared with control cultured cells (P < 0.05). In addition, expression of AMH was greater in granulosa cells cultured with BMP2, BMP6, or BMP15 when compared with controls (P < 0.05). Finally, treatment with recombinant human AMH, in vitro, inhibited CYP19A1 expression in a dose-related (10–100 ng/mL) fashion, and reduced granulosa cell proliferation at 48 and 72 hours (P < 0.05). Results from these studies indicate that AMH signaling plays a role in both regulating granulosa cell proliferation and preventing granulosa cells from 5- to 8-mm follicles from undergoing premature differentiation before follicle selection.}, number={5}, journal={THERIOGENOLOGY}, author={Poole, Daniel H. and Ocon-Grove, Olga M. and Johnson, Alan L.}, year={2016}, month={Sep}, pages={1353–1360} }
@article{lyons_shaeffer_drewnoski_poore_poole_2016, title={Effect of protein supplementation and forage allowance on the growth and reproduction of beef heifers grazing stockpiled tall fescue}, volume={94}, ISSN={["1525-3163"]}, DOI={10.2527/jas.2015-9969}, abstractNote={Stockpiled tall fescue can provide adequate winter forage for beef cattle, although unsupplemented replacement heifers may display marginal performance before breeding. The objective of this study was to determine if protein supplementation and/or additional forage improves growth and reproductive performance of replacement heifers grazing stockpiled fescue. Cattle averaging 272 ± 1.59 kg were stratified by BW and then randomly assigned to 1 of 4 plots within a pasture replication. Treatment combinations were assigned in a 2 × 2 factorial arrangement and included 1) a conservative forage allocation ("normal," targeting 85% forage use) and mineral supplement (normal forage allocation with mineral supplement [FM]), 2) normal forage allocation with protein tub (FT), 3) more liberal forage allocation ("extra," targeting 70% forage use) and mineral supplement (extra forage allocation with mineral supplement [EM]), and 4) "extra forage allocation with protein tub (ET). Treatments were administered for 8 wk from early November to early January. Heifers were fed fescue hay for 1 wk before breeding in late January. Heifers were synchronized with the 7-d CO-Synch + controlled internal drug release device protocol and inseminated in late January. Heifers were checked for pregnancy by ultrasonography at 35 and 90 d after AI. Main and interaction effects between the 2 treatments were determined. Total supplement intake was greater for protein tub than mineral supplement (0.36 vs. 0.11 kg·heifer·d, respectively; < 0.0001), and the additional dietary protein in the tub groups resulted in greater serum urea N concentrations ( < 0.0001; 8.15 vs. 10.4 mg/dL for mineral and protein tub, respectively). Forage utilization efficiency was greater for normal than extra forage allocation (74.7 vs. 65.8%, respectively; < 0.0001). Main effects of both treatments on ADG were significant ( < 0.0001; 0.28, 0.43, 0.43, and 0.51 kg·heifer·d for FM, FT, EM, and ET, respectively). There was an interaction effect of the 2 treatments on change in BCS ( < 0.05; 0.12, 0.10, 0.18, and 0.31 for FM, FT, EM, and ET, respectively). Reproductive tract scores, pelvic area, and AI pregnancy rates were not different between treatments ( > 0.05). Overall, feeding a protein supplement or providing extra forage increased gain and interacted to increase BCS but did not have an effect on reproductive performance. Supplementing with protein and providing extra forage are strategies that can increase gain in heifers, which could aid heifers in reaching puberty before estrous synchronization.}, number={4}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Lyons, S. E. and Shaeffer, A. D. and Drewnoski, M. E. and Poore, M. H. and Poole, D. H.}, year={2016}, month={Apr}, pages={1677–1688} }
@article{pickworth_bell_greene_whisnant_poole_2017, title={Site of PGF 2α injection does not alter effectiveness of the Select Synch + controlled internal drug release and timed artificial insemination protocol}, volume={87}, ISSN={0093-691X}, url={http://dx.doi.org/10.1016/j.theriogenology.2016.08.018}, DOI={10.1016/j.theriogenology.2016.08.018}, abstractNote={Beef Quality Assurance programs have contributed to significant improvements in the wholesomeness of beef available for consumption. Injection site blemishes in the round have declined since the promotion of administering intramuscular injections in the neck. Unfortunately, many producers continue to administer estrus synchronization (ES) drugs in the rump. The objective of this study was to compare the effectiveness of injection site of PGF 2α , in ES protocols, on steroid hormone concentrations and pregnancy rates. A Select Synch + 7-day controlled internal drug release ES protocol was conducted with the site of PGF 2α injection alternated between neck and rump in beef cattle (n = 312) at the Ohio State University Agricultural Technical Institute and North Carolina State University. Blood samples (n = 75) were collected at controlled internal drug release insertion and at the time of artificial insemination (AI) to determine if progesterone (P4) and estrogen (E2) concentrations varied due to PGF 2α injection site. All cattle were confirmed pregnant by ultrasonography at approximately 30 and 90 days after insemination in North Carolina and approximately 70 days after insemination in Ohio. Data were analyzed as randomized complete block designs in PROC GLIMMIX with animal as the experimental unit. Differences were declared significant at P < 0.05. Site of PGF 2α injection, in either the neck or rump, did not affect (P > 0.05) overall conception rates in response to AI (58.4% and 55.6%, respectively). Altering PGF 2α injection site did not impact P4, E2 concentrations, or the P4:E2 ratio at AI (P > 0.05). However, cattle inseminated after displaying estrus had greater (P < 0.05) pregnancy rates than timed AI (67.8 vs. 47.5%, respectively). First service conception rates and pregnancy rates were consistent with previous reports. Overall, altering the location of the PGF 2α injection during ES did not change circulating hormone concentrations at AI or pregnancy rates; therefore, cattle producers should follow Beef Quality Assurance guidelines when administering ES protocols.}, journal={Theriogenology}, publisher={Elsevier BV}, author={Pickworth, C.L. and Bell, L.M. and Greene, W. and Whisnant, C.S. and Poole, D.H.}, year={2017}, month={Jan}, pages={161–166} }
@article{muth-spurlock_poole_whisnant_2016, title={Comparison of pregnancy rates in beef cattle after a fixedtime Al with once-or twice-used controlled internal drug release devices}, volume={85}, ISSN={["1879-3231"]}, DOI={10.1016/j.theriogenology.2015.09.019}, abstractNote={The use of fixed-time artificial insemination (FTAI) provides producers with numerous benefits including the use of superior genetics, shorter breeding and calving seasons, and a more uniform calf crop. However, the cost of implementing FTAI protocols is one of the several drawbacks hindering their use in the beef industry. Potential injection-site lesions from intramuscular injections of the hormones necessary for estrus synchronization are also a cause of concern for carcass quality. The objectives of this experiment were to (1) determine whether or not a twice-used controlled internal drug release (CIDR) device would be effective in an FTAI protocol without adversely affecting pregnancy rate and (2) whether or not the subcutaneous administration of PGF2α affects pregnancy rate. Nulliparous females (n = 99) between 13 and 27 months of age and multiparous cows (n = 43) between 48 and 74 months of age were synchronized for estrus using the 7-day CO-Synch + CIDR protocol. The females were randomly assigned to one of the two treatments: (1) a once-used CIDR (control) or (2) a twice-used CIDR device (treatment) incorporated into their synchronization protocol. The females were also randomly assigned to have their injection of PGF2α administered either intramuscularly or subcutaneously. Blood was taken in a random subset of nulliparous females (n = 52) just before device removal and assayed for concentration of progesterone. The concentration of progesterone was higher (P = 0.01) in the animals that received once-used CIDR devices than that in those received twice-used CIDR devices (3.4 ± 0.5 and 1.4 ± 0.5 ng/mL, respectively). There was no significant effect of parity (P = 0.82), artificial insemination technician (P = 0.60), PGF2α administration (P = 0.83), or treatment (P = 0.67) on pregnancy rates to artificial insemination which were 75.4 ± 6.0% and 71.7 ± 6.4%, for animals that received once- and twice-used CIDR devices, respectively. This study provides evidence that although concentration of progesterone is decreased in animals treated with a twice-used CIDR device, there is still a sufficient release of progesterone from the device to effectively synchronize estrus without adversely affecting the fertility of a herd.}, number={3}, journal={THERIOGENOLOGY}, author={Muth-Spurlock, A. M. and Poole, D. H. and Whisnant, C. S.}, year={2016}, month={Feb}, pages={447–451} }
@article{ndiaye_poole_walusimbi_cannon_toyokawa_maalouf_dong_thomas_pate_2012, title={Progesterone effects on lymphocytes may be mediated by membrane progesterone receptors}, volume={95}, ISSN={0165-0378}, url={http://dx.doi.org/10.1016/j.jri.2012.04.004}, DOI={10.1016/j.jri.2012.04.004}, abstractNote={Luteal cell-induced proliferation of T lymphocytes devoid of the nuclear progesterone receptor (PGR) is inhibited by progesterone. Functional effects of progesterone on bovine lymphocytes and the expression of membrane progesterone receptors (mPRs) alpha (PAQR7), beta (PAQR8), gamma (PAQR5), and progesterone receptor membrane component 1 (PGRMC1) mRNA were analyzed in corpus luteum (CL) and lymphocytes. Progesterone and a cell-impermeable progesterone conjugate caused a dose-dependent decrease in IL2 receptor α-subunit (IL2RA) mRNA and an increase in interleukin 2 (IL2) mRNA concentrations in cultured PBMCs. In luteal tissues, concentrations of PAQR7 and PAQR8 mRNA were lower in CL collected on day 11 compared with day 18, whereas PGRMC1 and PGR mRNA were greater on day 11 than on day 18. The mRNA of all three PAQRs and PGRMC1 were detected in bovine T lymphocytes, but not in B cells/monocytes. Progesterone increased intracellular Ca(++) and reduced the phosphorylation of zeta-chain-associated protein kinase 70 (Zap70). A specific, saturable, and single progesterone binding site with a steroid specificity characteristic of mPRs was demonstrated by saturation and competitive binding assays using T lymphocyte membranes, and PAQR7 receptors were localized on the plasma membranes by immunofluorescence. Thus, progesterone induces specific and rapid functional effects on T lymphocytes in the absence of PGR. The mPRs are potential intermediaries of the cell-surface actions of progesterone because they are expressed in lymphocytes, the actions of progesterone are mimicked by a cell-impermeable form of progesterone, and specific, saturable progesterone binding, which is characteristic of mPRs, is present on lymphocyte membranes.}, number={1-2}, journal={Journal of Reproductive Immunology}, publisher={Elsevier BV}, author={Ndiaye, Kalidou and Poole, Daniel H. and Walusimbi, Sadhat and Cannon, Matthew J. and Toyokawa, Koji and Maalouf, Samar W. and Dong, Jing and Thomas, Peter and Pate, Joy L.}, year={2012}, month={Sep}, pages={15–26} }
@article{lingenfelter_dailey_inskeep_vernon_poole_rhinehart_yao_2008, title={Microarray analysis of gene expression in granulosal cells from persistent follicles in cattle}, volume={104}, ISSN={0378-4320}, url={http://dx.doi.org/10.1016/j.anireprosci.2007.07.014}, DOI={10.1016/j.anireprosci.2007.07.014}, abstractNote={Granulosal cells form highly specialized membrane connections with the oocyte and each other, allowing the passage of regulatory molecules and metabolites between cells. Gene expression changes in granulosal cells may adversely affect oocyte competence resulting in early embryonic loss. The present study was conducted to analyze global gene expression profiles in granulosal cells from persistent ovarian follicles in cows. Cows were assigned randomly to two groups: growing follicles on day 8 and persistent follicles on day 15 of the estrous cycle (estrus=day 0). Cows in the persistent follicle group received progesterone from CIDR-B devices on days 4 through 13. Granulosal cells were collected from both growing and persistent follicles and used in a direct comparison microarray experiment using a bovine long oligo array representing approximately 8400 known genes. Analysis of the microarray data revealed up-regulation of 272 genes (M-value>or=0.9) and down-regulation of 203 genes (M-value