@article{llanes_whisnant_knox_farin_2019, title={Assessment of ovulation synchronization protocols in goats and use of pregnancy specific protein B (PSPB) enzyme linked immunsorbent assay (ELISA) to determine kid number at birth}, volume={67}, ISSN={["1879-0054"]}, DOI={10.1016/j.domaniend.2018.11.002}, abstractNote={The efficacy of several protocols for ovulation synchronization and timed artificial insemination (TAI) in goats was examined. In addition, the relationship between levels of pregnancy specific protein B (PSPB) during gestation assessed with a commercially available ELISA and the number of offspring at birth was determined. In Experiment 1, 70 does were randomized into four treatments: (1) breed by estrus [BBE], (2) 6-d treatment with a new [C6N], (3) once-used [C61], or (4) twice-used Controled Internal Drug Release (CIDR) device [C62)]. BBE does received two 15 mg doses of prostaglandin-F2α (PGF) at a 10-d interval and were bred 12 h after estrus onset. CIDR groups received a CIDR for 6 d with 15 mg PGF given at CIDR removal. TAI was performed 48 h after CIDR removal and does were given 50 μg GnRH. All does were inseminated with a single dose of frozen semen using a non-surgical, transcervical technique. Pregnancy rates for the BBE, C6N, C61 and C62 treatment groups were 39% ± 12%, 64% ± 12%, 77% ± 12% and 57% ± 12%, respectively, and did not differ. Reuse of CIDRs, even with reuse extending for a total of 21 d, was as effective as new CIDRs for synchronization of ovulation. In Experiment 2, 68 does were randomized into four treatments: (1) BBE, (2) C6N, (3) NC.Synch [NCS], (4) modified NCS [NCSM]. The BBE and C6N groups were as described for Experiment 1. The NCS and NCSM groups received 15 mg PGF on Day 1, 50 μg GnRH on Day 8 and 15 mg PGF on Day 15 (NCS) or Day 15.5 (NCSM). Does were bred by TAI at 72 h (NCS) or 60 h (NCSM) after the second PGF injection. All does in the NCS and NCSM groups received 50 μg GnRH at TAI. Pregnancy rates were 53% ± 12%, 30% ± 11%, 50% ± 11% and 41% ± 12% for does in the BBE, C6N, NCS and NCSM group, respectively, and did not differ. In Experiment 3, 62 does pregnant to TAI were bled at Days 48 and 85 post-insemination for PSPB. Data on kid numbers and birth weights were subsequently recorded. At Day 48 of gestation, PSPB levels for does birthing singletons were lower than for does birthing twins or triplets (25.0 ± 0.1a, 28.8 ± 0.1b and 30.7 ± 0b ng/mL, respectively, abP<0.05). At Day 85 of gestation, PSPB levels were progressively greater for does birthing singletons versus twins versus triplets (27.0 ± 0.1a, 28.5 ± 0.1b and 31.6 ± 0c ng/mL, abcP<0.05). In conclusion, PSPB concentrations detected using a commercially available ELISA at Day 48 or 85 of gestation could distinguish does carrying single versus multiple fetuses.}, journal={DOMESTIC ANIMAL ENDOCRINOLOGY}, author={Llanes, A. and Whisnant, C. S. and Knox, W. B. and Farin, C. E.}, year={2019}, month={Apr}, pages={54–62} }
 @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 PGF2α, 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 PGF2α 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 PGF2α 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 PGF2α 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 PGF2α 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 PGF2α 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{reis_huntington_hopkins_whisnant_paulino_2015, title={Herbage selection, intake and digestibility in grazing beef cattle}, volume={174}, ISSN={["1878-0490"]}, DOI={10.1016/j.livsci.2015.01.020}, abstractNote={The objectives of this study were to measure voluntary herbage intake in kg of dry matter (DM) per day and in proportions of plant species and components (leaf, stem, dead material) of nonlactating Angus cows under grazing conditions and compare DM herbage intakes to intakes of the same cows when they were nursing their calves. Twenty nonlactating Angus cows (50±12 mo of age, 525±55 kg weight) were selected from a larger herd to create 4 groups of 5 cows with average DM intakes that ranged from 11 to 15 kg/d during lactation. The cows were allocated for 28 d as a group on the pasture that contained 5540 kg DM/ha as tall fescue (Festuca arundinacea), bermudagrass (Cynodon dactylon var. Tifton-85), red clover (Trifolium pratense) and other plants. Pasture composition was measured by visual appraisal and manual separation of pasture clippings. Daily allocations provided approximately 2.5 kg DM/100 kg BW. Each cow was individually fed 0.82 kg supplement DM daily that contained 498 mg of the n-alkane dotriacontane (C32) and 448 mg hexatriacontane (C36) during the last 14 d. Fecal grab samples were collected from each cow during the last 5 d. Grazing intake (8.92±1.5 kg DM/d) was calculated for each cow from C32 intake and ratios of tritriacontane (C33):C32 in feces and did not differ (P=0.97) among cow groups. Individual cow intakes during lactation and after weaning, during grazing, were not correlated. Measured sward and calculated intake proportions of tall fescue (0.58 and 0.65), bermudagrass (0.38 and 0.33), and red clover (0.02 and 0.01) indicated cows selected slightly more tall fescue and less bermudagrass and red clover than was on offer. Manual separations of sward and calculated intake proportions of dead material and stem (0.89 and 0.95), green leaf (0.10 and 0.02) and other material (0.01 and 0.04) were similar. N-alkanes provided credible calculations of intake by grazing cows. Intakes of lactating cows did not predict their intake after weaning.}, journal={LIVESTOCK SCIENCE}, author={Reis, S. F. and Huntington, G. and Hopkins, M. and Whisnant, S. and Paulino, P. V. R.}, year={2015}, month={Apr}, pages={39–45} }
 @article{barnwell_farin_whisnant_alexander_farin_2015, title={Maternal serum progesterone concentration and early conceptus development of bovine embryos produced in vivo or in vitro}, volume={52}, ISSN={["1879-0054"]}, DOI={10.1016/j.domaniend.2015.03.004}, abstractNote={The hormone progesterone is essential for proper embryonic development. The objective of this study was to examine the relationship between recipient serum concentrations of progesterone, at the time of embryo transfer and at conceptus recovery, on conceptus development from in vivo- or in vitro-produced embryos. Embryos were produced in vivo by superovulation of Holstein cows (IVO; n = 17) or in vitro with either serum-containing (IVPS; n = 27) or serum-restricted medium (IVPSR; n = 34). Single grade I blastocysts from each embryo production system were transferred into heifers on day 7 of development. Conceptuses were recovered on day 17 of gestation and classified as complete, degenerated, or no conceptus. Compared with the IVO group, in vitro-produced embryos had more (P = 0.055) degenerated conceptuses (IVO, 0%; IVPS, 18.5%; and IVPSR, 20.6%). There were no differences in progesterone concentrations at the time of transfer when recipients received either male or female embryos (P > 0.05). Progesterone concentrations in recipients receiving in vivo-produced embryos were higher (P < 0.05; 3.74 ± 0.4 ng/mL; least-squares mean ± standard error of the mean) on day 7 compared with those receiving in vitro-produced embryos (IVPS, 2.4 ± 0.2; IVPSR, 2.58 ± 0.3 ng/mL). However, there was no difference in progesterone concentration on day 7 between treatment groups for heifers from which short conceptuses (≤194 mm) were recovered on day 17. In contrast, when longer (>194 mm) conceptuses were recovered on day 17, heifers receiving in vitro-produced embryos had lower (P = 0.05) serum concentrations of progesterone on day 7 compared with those receiving in vivo-produced embryos (IVPS, 2.2 ± 0.5; IVPSR, 2.3 ± 0.5; IVO, 3.9 ± 0.5 ng/mL). In conclusion, differences in autonomy may exist between in vitro- and in vivo-produced embryos during the period of conceptus elongation with in vitro-produced embryos relying more on intrinsic factors to influence elongation.}, journal={DOMESTIC ANIMAL ENDOCRINOLOGY}, author={Barnwell, C. V. and Farin, P. W. and Whisnant, C. S. and Alexander, J. E. and Farin, C. E.}, year={2015}, month={Jul}, pages={75–81} }
 @article{coffman_pinto_snyder_leisinger_cole_whisnant_2014, title={Antiluteogenic effects of serial prostaglandin F-2 alpha administration in cycling mares}, volume={82}, ISSN={["1879-3231"]}, DOI={10.1016/j.theriogenology.2014.07.038}, abstractNote={A single dose of PGF2α does not consistently induce luteolysis in the equine CL until at least 5 days after ovulation, leading to the erroneous assumption that the early CL is refractory to the luteolytic effects of PGF2α. We hypothesized that serial administration of PGF2α in early diestrus would induce a return to estrus similar to mares treated with a single injection in mid-diestrus, and fertility of the induced estrus would not differ. The objectives of the study were to evaluate the effects of the 2 approaches as reflected by: (1) concentrations of plasma progesterone; (2) interovulatory and treatment-to-ovulation intervals; (3) the proportion of mares pregnant after artificial insemination. The study consisted of a balanced crossover design in which 10 reproductively normal Quarter Horse Mares were exposed to 2 treatments on 2 consecutive reproductive cycles. At detected ovulation (Day 0), mares were randomly allotted to 1 of 2 treatment groups: I, mid-diestrus treatment, administration of a single 10-mg dose of dinoprost tromethamine (PGF2α) im on Day 10; II, early diestrus treatment, administration of 10-mg PGF2α im twice daily on Days 0, 1, and 2 and once daily on Days 3 and 4. Mares in estrus and with a follicle 35 mm or greater in diameter were artificially inseminated with at least 2 billion motile sperm from a fertile stallion. Pregnancy was defined as detection of a growing embryonic vesicle on 2 consecutive examinations approximately 14 days after ovulation. Serial plasma samples were collected throughout the study period, and concentration of plasma progesterone was determined by RIA. A mixed-model ANOVA for repeated measures was used to analyze hormonal data. Interovulatory and treatment-to-ovulation intervals were compared by a paired t test and fertility by a McNemar chi-square analysis. All mares in group I underwent luteolysis after PGF2α administration denoted by mean (±SD) concentration of plasma progesterone of 0.25 ± 0.21 ng/mL detected 2 days after treatment. In group II, mean concentration of plasma progesterone remained below 1.0 ng/mL during treatment and until the onset of the next estrus. The mean interovulatory interval in group I was 18.5 ± 2.0 days compared with 13.1 ± 3.7 days in group II (P < 0.01). Treatment-to-ovulation intervals were 8.5 ± 2.0 days and 13.1 ± 3.7 days for groups I and II, respectively (P < 0.05). In both groups, 9 of 10 mares were pregnant (P = 1.0). Serial PGF2α administration beginning at ovulation consistently prevented luteal function in 10 of 10 mares in the present study without adversely affecting pregnancy rate of post-treatment cycles.}, number={9}, journal={THERIOGENOLOGY}, author={Coffman, E. A. and Pinto, C. R. F. and Snyder, H. K. and Leisinger, C. A. and Cole, K. and Whisnant, C. S.}, year={2014}, month={Dec}, pages={1241–1245} }
 @article{chitwood_phillips_whisnant_tyndall_lashley_deperno_2014, title={Serum Leptin as an Indicator of Fat Levels in White-tailed Deer (Odocoileus virginianus) in the Southeastern USA}, volume={50}, ISSN={["1943-3700"]}, DOI={10.7589/2013-08-223}, abstractNote={Abstract Leptin is a hormone that plays a key role in regulating energy intake, appetite, and metabolism. In some mammals, leptin has been shown to circulate at levels proportional to body fat, which could make it useful for nonlethal evaluation of body condition. Leptin's usefulness for estimating fat levels (i.e., body condition) of white-tailed deer (Odocoileus virginianus) is unknown. We quantified serum leptin concentrations in a sample of free-ranging, female deer collected in July 2008 and March 2009 from coastal North Carolina, USA. We compared leptin concentrations with kidney fat index, femur marrow fat index, and kidney fat mass. Additionally, we assessed differences in leptin concentrations between the two seasons, lactating and nonlactating females, and gestating and nongestating females. Leptin concentrations were similar between seasons but were lower in lactating and gestating females. We did not detect significant relationships between leptin and the body fat metrics, indicating that leptin may have limited value for estimating fat reserves in white-tailed deer.}, number={4}, journal={JOURNAL OF WILDLIFE DISEASES}, author={Chitwood, M. Colter and Phillips, Shannon P. and Whisnant, Scott and Tyndall, James and Lashley, Marcus A. and DePerno, Christopher S.}, year={2014}, month={Oct}, pages={887–890} }
 @article{meyer_whitley_morrow_stikeleather_baird_rice_halbert_styles_whisnant_2013, title={Effect of physical and inhaled euthanasia methods on hormonal measures of stress in pigs}, volume={21}, number={5}, journal={Journal of Swine Health and Production}, author={Meyer, R. E. and Whitley, J. T. and Morrow, W. E. M. and Stikeleather, L. F. and Baird, C. L. and Rice, J. M. and Halbert, B. V. and Styles, D. K. and Whisnant, C. S.}, year={2013}, pages={261–269} }
 @article{bowdridge_knox_whisnant_farin_2013, title={NCSynch: A novel, progestagen-free protocol for ovulation synchronization and timed artificial insemination in goats}, volume={110}, ISSN={["1879-0941"]}, DOI={10.1016/j.smallrumres.2012.07.025}, abstractNote={The objective of this study was to compare overall pregnancy success achieved using a combined ovulation synchronization-timed artificial insemination (NCSynch-TAI) protocol with that obtained using estrus synchronization and artificial insemination (AI). Multiparous Boer and Boer-cross does (n = 132) were randomly assigned within age (year 1) or parity (years 2 and 3) to one of two treatments. Control does received 15 mg prostaglandin F (PGF; Lutalyse®) on days 1 and 10 of treatment. Estrus onset was checked twice daily with separately penned, intact bucks (year 1) or a vasectomized buck penned with the does (years 2 and 3). Control does were bred by AI 12 h after estrus onset using frozen semen. NCSynch-TAI does received 15 mg PGF on day 1 of treatment. Does received 50 μg GnRH (Cystorelin®) on day 8, and 15 mg PGF was given on day 15. On day 18, NCSynch-TAI does were appointment bred using frozen semen and received 50 μg GnRH at breeding. Pregnancy status was determined using transabdominal ultrasonagraphy with kidding rates also recorded. In year 1, 13 of 15 control does (87%) were detected in estrus with 8 pregnant to AI for an overall pregnancy rate of 53%. For NCSynch-TAI, 15 does were bred and 11 (73%) became pregnant. In year 2, 24 of 26 controls (92%) were detected in estrus with 19 pregnant to AI (73% overall pregnancy rate). For NCSynch-TAI, 26 does were bred and 20 (77%) became pregnant. In year 3, 21 of 25 controls (84%) were detected in estrus with 8 pregnant to AI (32% overall pregnancy rate). For NCSynch-TAI, 25 does were bred and 14 (56%) became pregnant. Across all years, the overall pregnancy rate for NCSynch-TAI does (45/66, 68%) did not differ (P = 0.075) compared to controls (35/66; 53%). Kidding rates for the two treatments (68% vs. 51%, respectively) also did not differ (P = 0.075). In summary, pregnancy success following the use of NCSynch-TAI was comparable to that obtained when does were bred based on detection of estrus.}, number={1}, journal={SMALL RUMINANT RESEARCH}, author={Bowdridge, E. C. and Knox, W. B. and Whisnant, C. S. and Farin, C. E.}, year={2013}, month={Feb}, pages={42–45} }
 @article{spears_whisnant_huntington_lloyd_fry_krafka_lamptey_hyda_2012, title={Chromium propionate enhances insulin sensitivity in growing cattle}, volume={95}, ISSN={["1525-3198"]}, DOI={10.3168/jds.2011-4845}, abstractNote={Thirty-six Angus and Angus×Simmental heifers, averaging 291 kg, were used to determine the effects of dietary Cr, in the form of Cr propionate (Cr Prop), on glucose metabolism and serum insulin concentrations following glucose administration. Heifers were stratified by body weight (BW) within a breed and randomly assigned to treatments. Treatments consisted of 0, 3, 6, or 9 mg of supplemental Cr/d from Cr Prop. Based on dry matter (DM) intakes, the daily doses of Cr were equivalent to 0.47, 0.94, and 1.42 mg of supplemental Cr/kg of DM. Heifers were individually fed a corn silage-based diet at a level of 2% of BW. Each heifer was also fed 0.45 kg of a ground corn supplement daily that served as a carrier for supplemental Cr. Glucose tolerance tests were performed on d 44 of the study. Glucose was infused via jugular catheters at a level of 0.45 g/kg of BW(0.75) over a course of 1 to 2 min. Blood samples were collected at -10, 0, 5, 10, 15, 30, 45, 60, 90, 120, 150, and 180 min relative to glucose dosing for glucose and insulin determination. Area under the glucose response curve was lower (1,603 vs. 1,964 mg/dL per minute) in heifers supplemented with Cr from 0 to 45 min following glucose challenge. Serum insulin concentrations were lower in Cr-supplemented heifers than in controls following glucose infusion. The molar ratio of insulin to glucose was also lower in Cr-supplemented heifers relative to controls. Serum insulin and serum insulin to glucose ratios did not differ among heifers supplemented with 3, 6, or 9 mg of Cr/d. Results indicate that Cr Prop supplementation increased tissue sensitivity to insulin in growing heifers. Based on insulin sensitivity, Cr requirements (as Cr Prop) of growing heifers can be met by supplementing with 3 mg of Cr/d or 0.47 mg of Cr/kg of DM.}, number={4}, journal={JOURNAL OF DAIRY SCIENCE}, author={Spears, J. W. and Whisnant, C. S. and Huntington, G. B. and Lloyd, K. E. and Fry, R. S. and Krafka, K. and Lamptey, A. and Hyda, J.}, year={2012}, month={Apr}, pages={2037–2045} }
 @article{kick_tompkins_flowers_whisnant_almond_2012, title={Effects of stress associated with weaning on the adaptive immune system in pigs}, volume={90}, ISSN={["0021-8812"]}, DOI={10.2527/jas.2010-3470}, abstractNote={This study was designed to investigate the effects of weaning age on specific components of the adaptive immune system in pigs. Twenty-three crossbred pigs were randomly assigned to 1 of 3 treatments: weaning at 14 (14D, n = 8), 21 (21D, n = 7), or 28 (28D, n = 8) d of age. Peripheral blood samples, obtained when pigs were 13, 15, 20, 22, 27, 29, and 35 d of age, were analyzed for peripheral blood cell percentages and concentrations of neutrophils, lymphocytes, T cell subsets, mature B cells, and plasma cortisol concentrations. For each of the 3 groups, weaning increased plasma cortisol concentrations (P < 0.001) and reduced BW percentage change (P < 0.017). Lymphocyte concentrations displayed a treatment effect for the 14D (P = 0.074) and 28D (P = 0.014) groups. Albeit inconsistent, lymphocyte concentrations were less in weaned pigs on the day after weaning than in pigs remaining on the sow or weaned at a younger age. Specifically, mature B cells (CD21(+)) and CD4(+)CD8(+) cells decreased (P < 0.05) after weaning at 28 d of age. Other differences occurred among treatments; however, the differences apparently were not associated with weaning. Based upon the immunological measures used in the present study, there was not an explicit benefit to the adaptive immune system for any weaning age. Early weaning did not negatively affect the adaptive immunological competence of pigs as determined by changes in populations of immune cells.}, number={2}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Kick, A. R. and Tompkins, M. B. and Flowers, W. L. and Whisnant, C. S. and Almond, G. W.}, year={2012}, month={Feb}, pages={649–656} }
 @article{velie_cassady_whisnant_2012, title={Endocrine response to acute stress in pigs with differing backtest scores}, volume={145}, ISSN={["1878-0490"]}, DOI={10.1016/j.livsci.2012.01.008}, abstractNote={In an attempt to quantify a pig's behavioral reaction to stress, pigs in previous studies were subjected to a backtest. Pigs scoring high on the backtest were thought to have a greater reaction to stress than those scoring lower on the test. To further understand this reaction eighty-eight gilts from 19 L were tested twice using the backtest. Gilts with the greatest (n = 15, High) and least (n = 15, Low) total time struggling were then selected for acute stress challenges. Pigs, in two replicates, were fitted with jugular cannulas at approximately 150 d of age. An acclimation time of 24 h was given between cannulation, testing and between tests. Blood samples were collected at 10 time points (− 60, − 30, 0, 5, 10, 15, 30, 60, 90, and 120 m relative to the application of the stressor). Pigs were challenged with 0.11 mol/kg BW of corticotropin releasing hormone (CRH) (n = 9 High, n = 9 Low) injected through the cannula to test the proposed model. The first stressor was snaring the pig with a nose-snare for 1 min (n = 10 High, n = 9 Low). The second stressor was depriving the pigs of feed for 24 h followed by placing feed next to the pig but out of reach (n = 6 High, n = 7 Low). Plasma samples were assayed for cortisol, epinephrine, and norepinephrine. Data were analyzed using a model including fixed effects of time, replicate, and group (High or Low) and all two-way interactions. In response to the CRH challenge, cortisol levels peaked at 10 m and returned to basal levels by 90 m. Least squares means response in norepinephrine of the High exceeded Low at 5 m by 376 ± 99 pg/mL. Cortisol, epinephrine, and norepinephrine response to snaring was similar. Cortisol peaked at 10 m and epinephrine and norepinephrine at 5 m. The response to feed deprivation failed to exceed basal levels. Response to the CRH challenge demonstrated the appropriateness of the model and that High and Low pigs were equally capable of responding. The biological significance of differences between High and Low groups in norepinephrine levels at 5 m following snaring is unknown.}, number={1-3}, journal={LIVESTOCK SCIENCE}, author={Velie, B. D. and Cassady, J. P. and Whisnant, C. S.}, year={2012}, month={May}, pages={140–144} }
 @article{lefrapper_walston_whisnant_2010, title={Comparison of Various Extenders for Storage of Cooled Stallion Spermatozoa for 72 Hours}, volume={30}, ISSN={["1542-7412"]}, DOI={10.1016/j.jevs.2010.02.007}, abstractNote={Abstract Multiple extenders have been developed to preserve cooled stallion semen. Comparisons of some extenders have been made but there is need for further research in this area. Extenders tested included EZ Mixin (Animal Reproduction Systems, Chino, CA), Kenney's, Universal (NASCO, Fort Atkinson, WI), EquiPro, EquiPro CellGuard (Minitube of America, Verona, WI), and INRA 96 (IMV, Maple Grove, MN). Semen was collected and each ejaculate was divided and extended in each of the aforementioned extenders and stored at 4°C. Motility measures were determined using computer-assisted sperm analysis at 0, 24, 48, and 72 hours after collection. Samples were evaluated for total motility, progressive motility (PM), straight-line velocity, curvilinear velocity, straight-line distance, and curvilinear distance. Total motility and PM decreased over time in storage (P}, number={4}, journal={JOURNAL OF EQUINE VETERINARY SCIENCE}, author={LeFrapper, L. and Walston, L. and Whisnant, C. S.}, year={2010}, month={Apr}, pages={200–204} }
 @article{hammam_whisnant_elias_zaabel_hegab_abu-el naga_2010, title={Effect of media, sera and hormones on in vitro maturation and fertilization of water buffalos (Bubalus bubalis)}, volume={9}, DOI={10.3923/javaa.2010.27.31}, number={1}, journal={Journal of Animal and Veterinary Advances}, author={Hammam, A. M. and Whisnant, C. S. and Elias, A. and Zaabel, S. M. and Hegab, A. O. and Abu-El Naga, E. M.}, year={2010}, pages={27–31} }
 @article{reynolds_elias_whisnant_2010, title={Effects of feeding pattern on ghrelin and insulin secretion in pigs}, volume={39}, ISSN={["1879-0054"]}, DOI={10.1016/j.domaniend.2010.02.006}, abstractNote={Ghrelin is a peptide hormone that has been implicated in the regulation of feed intake, but little is known about its secretion in pigs. Hence, the effect of feeding pattern on the regulation of ghrelin secretion was tested. In experiment 1, barrows were allotted randomly into 1 of 2 groups, (1) ad libitum fed (CONT) and (2) limited access to feed (once per day, MEAL). Blood samples were taken through jugular catheters every 15 min for 6 h after 7 d on the experimental feeding regimen. Plasma concentrations of ghrelin and insulin were determined by radioimmunoassay. Ghrelin concentrations in the MEAL pigs were elevated before feeding and declined after feeding (P < 0.01). No pattern in plasma ghrelin concentrations was observed in the CONT pigs, but ghrelin concentrations were lower than in the MEAL group. Insulin concentrations were greater in CONT pigs (P < 0.01) during most of the sampling and increased after feeding in the MEAL pigs (P < 0.01). In experiment 2, the treatments were the same as in experiment 1; however, the amount of feed was increased in the MEAL group so that their daily intake was similar to the CONT pigs. Ghrelin concentrations in the MEAL group were again elevated before the meal and declined afterward (P < 0.01). Insulin but not glucose concentrations were negatively correlated with ghrelin. Once-per-day feeding resulted in increased plasma concentrations of ghrelin, which decreased after feeding. Ghrelin may be involved in the regulation of feed intake in pigs.}, number={2}, journal={DOMESTIC ANIMAL ENDOCRINOLOGY}, author={Reynolds, C. B. and Elias, A. N. and Whisnant, C. S.}, year={2010}, month={Aug}, pages={90–96} }
 @article{sauve_huntington_whisnant_burns_2010, title={Intake, Digestibility, and Nitrogen Balance of Steers Fed Gamagrass Baleage Topdressed at Two Rates of Nitrogen and Harvested at Sunset and Sunrise}, volume={50}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2009.02.0105}, abstractNote={ABSTRACT}, number={1}, journal={CROP SCIENCE}, author={Sauve, A. K. and Huntington, G. B. and Whisnant, C. S. and Burns, J. C.}, year={2010}, pages={427–437} }
 @article{farin_dowdall_hicks_farin_whisnant_2009, title={SUBCUTANEOUS ADMINISTRATION OF FOLLICLE STIMULATING HORMONE FOR SUPEROVULATION OF HOLSTEIN COWS}, volume={21}, ISSN={["1031-3613"]}, DOI={10.1071/RDv21n1Ab293}, abstractNote={
Follicle stimulating hormone (FSH) is usually administered in a series of intramuscular (IM) injections to induce multiple ovulations for embryo production in cattle and other species. The objective of this study was to determine the superovulatory response of dairy cows to subcutaneous (SC) administration of FSH using a reduced number of injections in combination with a progesterone-releasing device. Eighteen non-lactating Holstein cows initially received 25 mg Prostaglandin F2α IM (PGF; Lutalyse; Pfizer Animal Health, Groton, CT, USA) on Day –7. All cows then received an intravaginal progesterone-releasing device (CIDR-B, 1.38 mg progesterone; Pfizer Animal Health) on Day 0, and 100 μg GnRH IM (Cystorelin; Merial Ltd, USA) on Day 2. Cows were randomly assigned to receive a total of 400 mg (20 mL) of FSH (Folltropin-V; Bioniche Animal Health, USA) either by IM injection (IM Group, n = 9 cows) given at 12 h intervals on Days 4 (60 mg, 60 mg), 5 (55 mg, 55 mg), 6 (45 mg, 45 mg) and 7 (40 mg, 40 mg), or by SC injection (SC Group, n = 9 cows) given at 24 h intervals on Days 4 (140 mg), 5 (140 mg) and Day 6 (120 mg). On Day 7, CIDR-B inserts were removed and cows received two 25 mg PGF IM injections given 12 h apart. Cows were artificially inseminated at 12 and 24 h after standing estrus. Blood samples were obtained from all cows at 0, 2, 4, 8, 12, 24, 36, 48, 60, 72, and 84 h after the first FSH injection for determination of serum FSH concentrations. Ovarian follicles and CL were monitored using ultrasonography on Days 4, 7, and 16. Embryos were recovered non-surgically on Day 16 (7 days after estrus). The effects of treatment on follicular response and embryo yield were analyzed by Wilcoxon test, and the response of cows to treatment was analyzed by chi-square test. The effects of treatment on concentrations of serum FSH were analyzed using ANOVA for repeated measures. There was no effect (P > 0.05) of route of FSH administration on the concentrations of serum FSH at any time point. The superovulatory response of cows to treatment, defined as greater than 2 CL per cow, did not differ (P > 0.05) between the IM (77.8%, 7/9 cows) and SC (88.9%, 8/9 cows) Groups. There was also no difference (P > 0.05) between the IM and SC Groups for the number of 5 to 10 mm follicles prior to FSH treatment (mean ± SEM; 0.6 ± 0.2 v. 0.9 ± 0.4), the total number of follicles after FSH treatment (12.4 ± 1.6 v. 12.7 ± 2.2) or the number of CL at embryo recovery (6.4 ± 1.5 v. 10.4 ± 2.1). Similarly, there were no differences (P > 0.05) between the IM and SC Groups for total number of oocytes/embryos (5.6 ± 2.6 v. 13.0 ± 4.3), transferable embryos (Grade 1, 2, 3; 3.0 ± 1.4 v. 6.1 ± 2.9) or Grade 1 embryos (2.9 ± 1.4 v. 4.3 ± 2.5). In conclusion, administration of FSH using 3 SC injections in combination with a progesterone-releasing device was an effective method for superovulation of Holstein cows.

Supported by USDA Animal Health Formula Funds and the State of North Carolina.

}, number={1}, journal={REPRODUCTION FERTILITY AND DEVELOPMENT}, author={Farin, P. W. and Dowdall, K. M. and Hicks, J. E. and Farin, C. E. and Whisnant, C. S.}, year={2009}, pages={243–244} }
 @article{rose_tucker_willard_williams_fuquay_ryan_whisnant_2008, title={Evaluation of hormone treatments in a modified ovulation synchronization protocol in dairy heifers}, volume={7}, number={2}, journal={Journal of Animal and Veterinary Advances}, author={Rose, C. and Tucker, W. B. and Willard, S. T. and Williams, A. and Fuquay, J. and Ryan, P. L. and Whisnant, C. S.}, year={2008}, pages={154–159} }
 @article{schramme_pinto_davis_whisnant_whitacre_2008, title={Pharmacokinetics of carbetocin, a long-acting oxytocin analogue, following intravenous administration in horses}, volume={40}, ISSN={["0425-1644"]}, DOI={10.2746/042516408X334343}, abstractNote={Summary}, number={7}, journal={EQUINE VETERINARY JOURNAL}, author={Schramme, A. R. and Pinto, C. R. F. and Davis, J. and Whisnant, C. S. and Whitacre, M. D.}, year={2008}, month={Nov}, pages={658–661} }
 @article{stahlhut_whisnant_lloyd_baird_legleiter_hansen_spears_2006, title={Effect of chromium supplementation and copper status on glucose and lipid metabolism in Angus and Simmental beef cows}, volume={128}, ISSN={["1873-2216"]}, DOI={10.1016/j.anifeedsci.2005.11.002}, abstractNote={Pregnant Angus (n = 83) and Simmental (n = 69) cows were blocked by age into three blocks and then randomly assigned by breed to one of two free choice mineral supplements to determine effects of dietary Cr and Cu status on glucose metabolism and blood metabolites in beef cows. Supplements consisted of: (1) control (no supplemental Cr) and (2) 40 mg Cr/kg of mineral (from Cr picolinate). Mineral supplements were formulated to contain all minerals typically supplemented to cattle diets with the exception of Cu. The study began approximately 75 days prepartum, at which time half of the cows in each treatment received a 25 g Cu oxide needle bolus. Blood was collected from 36 cows on days 28, 58, 97 (approximately 20-day postpartum), 155, 210, and 279 for plasma glucose and non-esterified fatty acid (NEFA) determination. Chromium supplementation reduced (P<0.05) plasma glucose concentrations. Plasma glucose concentrations were also affected by breed × Cu bolus (P<0.05). In non-Cu supplemented cows, plasma glucose levels were higher (P<0.05) in Angus versus Simmental cows. In cows receiving a Cu bolus, plasma glucose levels were similar between breeds. Plasma NEFA concentrations were affected by time (P<0.01), Cr × Cu bolus (P<0.05), Cr × time (P<0.01), and Cr × block (P<0.01). On days 97 and 155, plasma NEFA concentrations were lower (P<0.01) in cows receiving Cr relative to control cows. Chromium supplementation reduced (P<0.01) plasma NEFA concentrations in 2 and 3 and 4 and 5-year-old cows but not in older cows, relative to control cows in those blocks. Chromium supplemented cows had lower (P<0.05) plasma NEFA concentrations than control cows that did not receive a Cu bolus. No differences in plasma NEFA concentrations occurred between treatments in cows that received a Cu bolus. At approximately 1-month prepartum and 1-month postpartum, 12 cows were cannulated in their jugular vein and glucose tolerance tests (GTT) were conducted. Cows used in GTT received 0.15 g of glucose/kg body weight as a 500 g/L dextrose solution. Chromium supplemented cows had lower plasma glucose (P<0.01), serum insulin (P<0.05) and NEFA (P<0.01) concentrations following the GTT conducted prepartum versus control cows. Clearance rates for glucose were not affected by treatment. In the postpartum GTT, plasma glucose was affected by an interaction between Cr supplementation and Cu status, as Cr supplemented cows that received a Cu bolus had higher (P<0.001) plasma glucose after glucose administration than cows not supplemented with Cu. No differences in plasma glucose occurred between control cows regardless of Cu status. Chromium supplemented cows had lower (P<0.05) serum insulin concentrations 10–45 min after glucose administration versus control cows. Results indicate that plasma glucose is lower in cows receiving supplemental Cr, and that an interaction between Cr and Cu status may alter glucose metabolism.}, number={3-4}, journal={ANIMAL FEED SCIENCE AND TECHNOLOGY}, author={Stahlhut, H. S. and Whisnant, C. S. and Lloyd, K. E. and Baird, E. J. and Legleiter, L. R. and Hansen, S. L. and Spears, J. W.}, year={2006}, month={Jun}, pages={253–265} }
 @article{stahlhut_whisnant_spears_2006, title={Effect of chromium supplementation and copper status on performance and reproduction of beef cows}, volume={128}, ISSN={["1873-2216"]}, DOI={10.1016/j.anifeedsci.2005.11.003}, abstractNote={Pregnant Angus (n = 83) and Simmental (n = 69) cows were blocked by age into three age blocks and then randomly assigned by breed within a block to one of two free choice mineral supplements to determine effects of dietary Cr and Cu status on performance and reproduction of beef cows. Supplements consisted of: (1) control (no supplemental Cr) and (2) 40 mg Cr/kg of mineral (from Cr picolinate). Mineral supplements were formulated to contain all minerals typically supplemented to cattle diets with the exception of Cu. The study began approximately 75 days prepartum, at which time half of the cows in each treatment received a 25 g Cu oxide needle bolus. Blood was collected from 36 cows on days 0, 28, 58, 97 (approximately 20 days postpartum), 155, 210, and 279, and from 36 calves on days 196 and 279 for plasma Cu determination. Liver biopsies were taken on days 0 and 279 to determine initial and final liver Cu concentrations in cows. Plasma Cu concentrations were affected by Cu bolus × time (P < 0.05), breed × time (P < 0.01), and breed × bolus (P < 0.01) interactions in cows, and by a treatment × time interaction (P < 0.05) in calves. Liver Cu concentrations were affected by breed × time (P < 0.01) and Cu bolus × time (P < 0.05) in cows. Cows receiving a Cu bolus had higher (P < 0.05) plasma Cu on day 97, and higher (P < 0.05) liver Cu on day 279 relative to cows that did not receive a bolus. Simmental cows had lower (P < 0.01) plasma Cu at day 28 and at subsequent sampling days, and lower (P < 0.01) liver Cu on days 0 and 279 than Angus cows. Simmental cows that received a Cu bolus had higher (P < 0.01) plasma Cu concentrations than Simmentals that did not receive supplemental Cu. Supplemental Cr resulted in higher (P < 0.05) plasma Cu concentrations in calves on day 279 versus controls. Overall body weight loss and body weight loss postpartum in cows was affected by breed (P < 0.05) and treatment × block (P < 0.01). Overall and postpartum body weight loss was lower in Angus cows (P < 0.05). Chromium supplementation reduced (P < 0.01) overall and postpartum body weight loss in 2 and 3 years old cows, but not in older cows. Cows supplemented with Cr tended (P < 0.06) to have higher pregnancy rates than controls. Calf birth weights and weaning weights were not affected by Cr or Cu bolus. Results indicate that Cr supplementation may improve fertility and decrease postpartum body weight loss especially in young beef cows.}, number={3-4}, journal={ANIMAL FEED SCIENCE AND TECHNOLOGY}, author={Stahlhut, H. S. and Whisnant, C. S. and Spears, J. W.}, year={2006}, month={Jun}, pages={266–275} }
 @article{hansen_spears_lloyd_whisnant_2006, title={Feeding a low manganese diet to heifers during gestation impairs fetal growth and development}, volume={89}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(06)72477-8}, abstractNote={A study was conducted to examine the effects of low dietary Mn on growth performance of pregnant heifers and fetal development of their offspring. Twenty pregnant Angus (n = 9) and Simmental (n = 11) heifers averaging 17 mo of age and 447.6 kg of initial body weight were used in the 267-d study. Heifers were selected from a previous study examining the effects of supplemental Mn on growth and reproductive performance of heifers. Ten pregnant heifers per treatment from the control (analyzed at 15.8 mg of Mn/kg of DM) and supplemental Mn (50 mg/kg of DM) treatments were randomly selected at the conclusion of the previous study to continue on their respective dietary treatments through gestation and early lactation. Serum cholesterol for the 267-d period was not affected by treatment. Whole-blood Mn concentration of heifers on d 267 was not affected by treatment. Whole-blood Mn concentration at birth was lower in calves born to control heifers than in those born to supplemented heifers. Calves born to control heifers weighed less at birth than those born to heifers receiving supplemental Mn. Calves born to control heifers suffered from varying signs of Mn deficiency, including superior brachygnathism, unsteadiness, disproportionate dwarfism, and swollen joints. Results suggest that feeding gestating heifers a diet containing 16.6 mg of Mn/kg of DM is not adequate for proper fetal development. Supplementation of 50 mg of Mn/kg of DM to the control diet was sufficient to overcome any signs of Mn deficiency in calves.}, number={11}, journal={JOURNAL OF DAIRY SCIENCE}, author={Hansen, S. L. and Spears, J. W. and Lloyd, K. E. and Whisnant, C. S.}, year={2006}, month={Nov}, pages={4305–4311} }
 @article{hansen_spears_lloyd_whisnant_2006, title={Growth, reproductive performance, and manganese status of heifers fed varying concentrations of manganese}, volume={84}, ISSN={["0021-8812"]}, DOI={10.2527/jas.2005-667}, abstractNote={An experiment was conducted to examine the effects of dietary Mn on growth, reproductive performance, and Mn status of beef heifers. Eighty Angus (n = 40) and Simmental (n = 40) heifers, averaging 249 kg, were stratified by BW within a breed and randomly assigned to 1 of 4 treatments providing 0 (control), 10, 30, or 50 mg of supplemental Mn/kg of DM from MnSO(4). Heifers were individually fed a diet containing cottonseed hulls, corn gluten feed, citrus pulp, and ground corn, and the control diet contained 15.8 mg of Mn/kg of DM by analysis. Average daily gain, DMI, and G:F for the 196-d period were not affected by Mn supplementation. Control heifers had reduced (P = 0.04) liver Mn when contrasted with the 3 levels of supplemental Mn. Serum cholesterol was greater (P = 0.001) in Angus compared with Simmental heifers over the course of the 196-d experiment but was not affected by treatment. Dietary Mn did not significantly affect measures of reproductive performance. Results of this study indicate that 15.8 mg of Mn/kg of diet DM should be adequate for growth, onset of estrus, and conception of beef heifers.}, number={12}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Hansen, S. L. and Spears, J. W. and Lloyd, K. E. and Whisnant, C. S.}, year={2006}, month={Dec}, pages={3375–3380} }
 @article{oliver_touchette_coalson_whisnant_brown_oliver_odle_harrell_2005, title={Pigs weaned from the sow at 10 days of age respond to dietary energy source of manufactured liquid diets and exogenous porcine somatotropin}, volume={83}, DOI={10.2527/2005.8351002x}, abstractNote={Previous research indicates that the neonatal pig does not alter feed intake in response to changes in the energy density of manufactured liquid diets. Also, the limited response of IGF-I to exogenous porcine ST (pST) previously observed in young pigs may be influenced by the source of dietary energy. Our objectives were to 1) determine the effect of a high-fat (HF; 25% fat and 4,639 kcal/kg ME; DM basis) or low-fat (LF; 2% fat and 3,481 kcal/kg ME; DM basis) manufactured liquid diet on pig performance; and 2) determine whether the limited response to exogenous pST in young pigs depends on the source of dietary energy. Two replicates of 60 pigs (n = 120; barrows and gilts distributed evenly), with an initial BW of 4,207 +/- 51 g, were weaned from the sow at 10 d of age and used in a randomized complete block design. Pigs were assigned by BW to one of six pens. Diets were formulated to provide a constant lysine:ME ratio and were fed on a pen basis for a duration of 9 d. On d 5, barrows and gilts within a pen were assigned randomly to receive either 0 or 120 microg of pST.kg BW(-1).d(-1) for 4 d. Pigs gained 336 +/- 9 g/d, which resulted in an ending BW of 7,228 +/- 120 g, regardless of dietary treatment (P > 0.15). Pigs fed the LF diet consumed 17% more DM per pen daily than pigs fed the HF diet (2,777 +/- 67 vs. 2,376 +/- 67 g/d, P < 0.01), but calculated ME intake did not differ between dietary treatments (P > 0.20). The G:F was 24% greater in HF- than in LF-fed pigs (P < 0.01). Plasma urea N concentrations were higher in the HF-fed pigs (11.0 +/- 0.6 mg/dL) than in pigs fed the LF diet (6.2 +/- 0.6 mg/dL; P < 0.05). Treatment with pST increased circulating IGF-I (P < 0.01) and decreased PUN (P < 0.01) concentration 32 and 25%, respectively, regardless of dietary treatment (P > 0.30). Circulating leptin averaged 1.8 +/- 0.1 ng/mL and was not affected by dietary treatment (P > 0.35) or pST (P > 0.40). These results suggest that the ST/IGF axis is responsive in the young pig and the increase in circulating IGF-I and growth is independent of the source of dietary energy. Also, young pigs respond to a lower energy density liquid diet with increased feed intake, without altering growth performance, apparently utilizing a mechanism other than circulating leptin.}, number={5}, journal={Journal of Animal Science}, author={Oliver, W. T. and Touchette, K. J. and Coalson, J. A. and Whisnant, C. S. and Brown, J. A. and Oliver, S. A. M. and Odle, J. and Harrell, R. J.}, year={2005}, pages={1002–1009} }
 @article{walker_robison_whisnant_cassady_2004, title={Effect of divergent selection for testosterone production on testicular morphology and daily sperm production in boars}, volume={82}, DOI={10.2527/2004.8282259x}, abstractNote={The objective of this study was to characterize correlated responses in testicular morphology and daily sperm production to divergent selection for testosterone production. Duroc boars from high and low lines (HTL and LTL, respectively) divergently selected over 10 generations for testosterone production in response to a GnRH challenge followed by random selection were used. Testicular tissues were sampled from all available males of generation 20 (HTL, n = 46; and LTL, n = 13). Volume densities for Leydig cells, seminiferous tubules, and Sertoli cells were estimated along with sperm production. The HTL boars had greater volume densities of Leydig cells than did LTL (P < 0.01). Volume density of seminiferous tubules tended to differ between lines (P < 0.07), but Sertoli cell volume densities did not differ (P < 0.27). Sperm production traits, adjusted for age, did not differ significantly between lines. Body, testicular, and epididymal weights were recorded for boars from HTL (n = 82) and LTL (n = 44) from generations 20 and 21. After adjustment for BW, average paired testicular weights for HTL and LTL were 417 and 457 g (P < 0.01), respectively. Epididymal weights, adjusted for BW, were heavier for HTL (P < 0.01) than for LTL. To demonstrate that the selection lines still differed for testosterone production, lines were evaluated in generation 21. Endogenous testosterone production of the HTL (n = 54) and LTL (n = 44) testosterone production line averaged 49.0 ng/mL and 27.8 ng/mL (P < 0.01), respectively. Plasma FSH concentrations did not differ between lines (P < 0.30). Selection for testosterone production in response to a GnRH challenge was an effective method of changing testosterone concentrations, testicular size, epididymal weight, and volume density of Leydig cells. However, daily sperm production per gram of testes was unchanged. Based on the results of this study, selection for testosterone production is not recommended as a method of increasing sperm production in pigs.}, number={8}, journal={Journal of Animal Science}, author={Walker, S. and Robison, O. W. and Whisnant, C. S. and Cassady, J. P.}, year={2004}, pages={2259–2263} }
 @article{willard_gandy_bowers_graves_elias_whisnant_2003, title={The effects of GnRH administration postinsemination on serum concentrations of progesterone and pregnancy rates in dairy cattle exposed to mild summer heat stress}, volume={59}, ISSN={["0093-691X"]}, DOI={10.1016/S0093-691X(02)01232-3}, abstractNote={The objective of this study was to evaluate whether administration of GnRH postinsemination would improve reproductive performance in heat-stressed dairy cattle. Estrous cycles of Holstein cows were synchronized using the OvSynch protocol and cows were artificially inseminated. Cows were then administered the following treatments: control (no GnRH; n=37), GnRH (100 microg) on Day 5 (GnRH-D5; n=34), or GnRH (100 microg) on Day 11 (GnRH-D11; n=34) postinsemination. Cows were provided access to both fans and sprinklers, and environmental data was collected hourly. Rectal temperatures and blood samples were obtained from cows on Days -9, -2, 0 (AI) and on alternate days from Day 5 to Day 19 postinsemination. Blood serum was collected for the analysis of progesterone (P(4)) by RIA. In a subset of cows (n=6/treatment) ultrasonography was performed on alternate days from Day 5 to Day 19 postinsemination to assess numbers of corpora lutea (CL) and CL cross-sectional areas. Pregnancy status of cows was confirmed at Day 30 postinsemination. Environmental data indicated that cows experienced mild heat stress during the trials (mean daily THI=73-77). Serum P(4) was greater (P<0.05) after Day 9 for GnRH-D5 cows and after Day 15 for GnRH-D11 cows through Day 19 postinsemination. The number of CLs present for GnRH-D5 cows was greater (P<0.05) on Day 17 than in either the control or GnRH-D11 treatment groups. On Day 17 postinsemination, both the GnRH-D5 and GnRH-D11 cows were observed to have greater (P<0.05) total CL tissue area than control cows. The interval from insemination to when serum P(4) returned to <1 ng/ml (i.e. luteolysis and return to estrus) did not differ (P>0.10) among treatment groups. Control cows (19%) tended to exhibit lower pregnancy rates (P<0.08) compared to the GnRH-D5 and GnRH-D11 treatment groups combined (35%). In summary, the treatment of heat-stressed dairy cows with GnRH postinsemination (Day 5 or 11) results in the appearance of more CL tissue, increased serum concentrations of P(4) and a tendency toward greater pregnancy rates.}, number={8}, journal={THERIOGENOLOGY}, author={Willard, S and Gandy, S and Bowers, S and Graves, K and Elias, A and Whisnant, C}, year={2003}, month={Apr}, pages={1799–1810} }
 @article{whisnant_harrell_2002, title={Effect of short-term feed restriction and refeeding on serum concentrations of leptin, luteinizing hormone and insulin in ovariectomized gilts}, volume={22}, ISSN={["0739-7240"]}, DOI={10.1016/S0739-7240(01)00126-6}, abstractNote={Ovariectomized gilts were either placed on full feed (FF) or restricted to one-third of the full feed amount (RST) for 7 days. Blood samples were taken through jugular catheters every 15 min for 4 h at the end of the 7-day period. Then dietary treatments were reversed and 7 days later samples were taken as before. Serum concentrations of leptin, insulin and luteinizing hormone (LH) were determined by radioimmunoassay. LH pulse frequency and mean serum leptin and insulin concentrations were lower (P<0.01) in RST than FF gilts. Reversal of treatment reversed the patterns of hormone secretion. These results confirm previous observations that feed restriction can inhibit pulsatile LH secretion and also decrease leptin and insulin secretion.}, number={2}, journal={DOMESTIC ANIMAL ENDOCRINOLOGY}, author={Whisnant, CS and Harrell, RJ}, year={2002}, month={Apr}, pages={73–80} }
 @article{whisnant_burns_2002, title={Evaluation of steroid microspheres for control of estrus in cows and induction of puberty in heifers}, volume={58}, ISSN={["0093-691X"]}, DOI={10.1016/S0093-691X(02)00942-1}, abstractNote={Two trials were designed to test whether a single treatment with a microsphere formulation of progesterone (P) could simulate the luteal phase of the estrous cycle and lead to estrus and subsequent luteal development. The first experiment was to characterize the pattern of serum P concentrations and estrus in cows treated with a microsphere formulation (P+E) that contained 625 mg P and 50 mg estradiol (E). Four cows with palpable corpora lutea were treated with 25 mg prostaglandin F2 α. Each cow was given P+E (i.m.) 12 h later. Tail vein blood samples were taken on Days 1 and 2 following P+E treatment and then three times weekly for 24 days. Serum P increased from 0.8±0.1 ng/ml at P+E treatment to 4.7±0.6 ng/ml on Day 1, declined gradually to 4.1±0.3 ng/ml on Day 7 and then declined more rapidly to 0.6±0.1 ng/ml on Day 13. Treated cows showed estrus 16.25±0.7 days after P+E treatment. Thereafter, serum P increased beginning on Day 20 after P+E treatment, as expected following estrus. In Experiment 2, Angus and Simmental heifers (10.5–11.5 months of age) were administered i.m. either the vehicle (controls), E (50 mg), P (625 mg) or P+E (n=13 per group). While treatment with E resulted in behavioral estrus (1–2 days after treatment) in each treated heifer, it did not (P>0.5) initiate estrous cycles as indicated by subsequent increased serum P. In contrast, the P and P+E treatments increased (P<0.05) the proportion (11/13) of heifers that showed estrus by 21 days after treatment followed by elevated serum P. We conclude that the microsphere formulation of P simulated the pattern of serum P concentrations during the luteal phase of the estrous cycle and initiated estrous cycles in peripubertal heifers with or without E.}, number={6}, journal={THERIOGENOLOGY}, author={Whisnant, CS and Burns, PJ}, year={2002}, month={Oct}, pages={1229–1235} }
 @article{whisnant_pagels_daves_2001, title={Effectiveness of a commercial early conception factor test for use in cattle}, volume={17}, ISBN={1080-7446}, DOI={10.15232/s1080-7446(15)31568-0}, abstractNote={The purpose of this study was to test the effectiveness of a commercially available early pregnancy test in cows. The test early conception factor (ECF™) was designed to distinguish between open and pregnant cows by detection of a protein present in blood serum or milk of pregnant cows. All tests were conducted on blood serum according to instructions of the manufacturer. Blood samples were taken via tail vein puncture between 6 and 15 d post-insemination from 67 Holstein or Jersey cows. Serum was placed in a test cassette and the results recorded after 2 h by three independent observers. Ultrasonography was performed on d 25 to 30 post-insemination, or rectal palpation was performed 35 to 42 d post-insemination by experienced personnel. These results were compared with the test results. The test results corresponded with the results of the ultrasound or rectal palpation 51% of the time. Of the 49% that disagreed, 25% were diagnosed pregnant by the ECF test but were found to be open by ultrasound or palpation, and 24% were diagnosed open by the test and found to be pregnant by ultrasound or palpation. These results suggest that the test does not perform at the necessary level of accuracy.}, number={1}, journal={Professional Animal Scientists}, author={Whisnant, C. S. and Pagels, L. A. and Daves, M. G.}, year={2001}, pages={51} }
 @article{reed_whisnant_2001, title={Effects of monensin and forage: concentrate ratio on feed intake, endocrine, and ovarian function in beef heifers}, volume={67}, ISSN={["1873-2232"]}, DOI={10.1016/S0378-4320(01)00118-X}, abstractNote={The objective of this study was to determine the effects of monensin (M) and altered forage:concentrate ratio (F:C) on feed intake, hormonal profiles, and ovarian function in beef heifers. Four ruminally cannulated heifers were maintained in metabolism crates and fed twice daily. Diets contained 0 or 200 mg per day M in diets of 70:30 (high forage, HF) or 30:70 (high concentrate, HC) F:C. Diets were limit fed to achieve isocaloric intake of calculated ME. Monensin supplementation had no effect on feed intake, but heifers fed HF had greater refusals compared with heifers fed HC (P<0.005). Serum insulin, progesterone, and estradiol concentrations did not differ between diets or treatments (P>0.10). Diet and/or treatment tended to alter the size or number of follicles on either or both ovaries. Monensin resulted in more waves of follicular development per estrous cycle with HF diets, but fewer with HC diets (P<0.07). The interovulatory interval, lifespan of the corpus luteum, and the size of the dominant follicle in the first two follicular waves were not different due to diet or treatment. However, the HC diet tended to produce a larger ovulatory follicle compared with the HF diet (HF=12.25, HC=13.5; P<0.08). We conclude that feeding monensin affects estradiol secretion and a higher proportion of concentrates alters ovarian dynamics, which could affect fertility in beef heifers.}, number={3-4}, journal={ANIMAL REPRODUCTION SCIENCE}, author={Reed, BK and Whisnant, CS}, year={2001}, month={Sep}, pages={171–180} }
 @article{melton_zaunbrecher_yoshizaki_patino_whisnant_rendon_lee_2001, title={Expression of connexin 43 mRNA and protein in developing follicles of prepubertal porcine ovaries}, volume={130}, ISSN={["1879-1107"]}, DOI={10.1016/S1096-4959(01)00403-1}, abstractNote={A major form of cell-cell communication is mediated by gap junctions, aggregations of intercellular channels composed of connexins (Cxs), which are responsible for exchange of low molecular weight (<1200 Da) cytosolic materials. These channels are a growing family of related proteins. This study was designed to determine the ontogeny of connexin 43 (Cx43) during early stages of follicular development in prepubertal porcine ovaries. A partial-length (412 base) cDNA clone was obtained from mature porcine ovaries and determined to have 98% identity with published porcine Cx43. Northern blot analysis demonstrated a 4.3-kb mRNA in total RNA isolated from prepubertal and adult porcine ovaries. In-situ hybridization revealed that Cx43 mRNA was detectable in granulosa cells of primary follicles but undetectable in dormant primordial follicles. The intensity of the signal increased with follicular growth and was greatest in the large antral follicles. Immunohistochemical evaluation indicated that Cx43 protein expression correlated with the presence of Cx43 mRNA. These results indicate that substantial amounts of Cx43 are first expressed in granulosa cells following activation of follicular development and that this expression increases throughout follicular growth and maturation. These findings suggest an association between the enhancement of intercellular gap-junctional communication and onset of follicular growth.}, number={1}, journal={COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY}, author={Melton, CM and Zaunbrecher, GM and Yoshizaki, G and Patino, R and Whisnant, S and Rendon, A and Lee, VH}, year={2001}, month={Aug}, pages={43–55} }