bluuebunny/crossref_metadata_2025 huggingface dataset:
200 Comparison of daily rotation and slow rotational grazing on ewe performance, parasite infestation, and soil
Authors: Bradley Kailey , Boyd Brooke , Garrison Lindsay , Higgins Morgan , Newton Robert , Vega Miranda , Gates Roger , Daniel Jay
Published: July 2019

Impact of grazing method on ewe performance, parasite infestation, and soil was examined using mature, non-lactating ewes divided into slow rotation (SR; n = 20) or daily rotation (DR; n = 20) groups. Pastures previously grazed by sheep were divided and soil sampled. Temporary electric fence provided daily pasture allocation for DR. Ewes had been adapted to temporary electric fence for two weeks. Both DR and SR were moved to new pasture at the same time. Ewes were weighed and fecal egg counts were conducted biweekly. On alternate weeks, ewes were body condition scored (BCS), FAMACHA scored, and dewormed if FAMACHA score was 4 or greater. After 10 weeks of grazing (June 1-August 10, 2018), final ewe weights and soil samples were collected. Body condition score, FAMACHA, fecal egg count, body weight, and soil test results were tested for effect of grazing group, date, and group by date interaction using procedures for repeated measures with JMP software (version 10, SAS Inst. Inc., Cary, NC). The FAMACHA scores were greatest on July 6 (P < 0.0001). BCS were greater on June 8 and 22 than July 6 and August 3 (P < 0.0001). Ewes were heaviest on June 1 and 15, lightest on July 27 and August 10 (P < 0.0001), and DR ewes were lighter than SR ewes on July 27 and August 10 (P < 0.0001). No effect of treatment, date, or treatment by date interaction on fecal egg count (P > 0.23) was detected. Soil organic matter decreased over the study (P = 0.0024), but organic matter change was less in DR than SR (P = 0.0092). DR did not influence parasitism, but may enhance soil organic matter.
203 Investing in parasite resistance in sheep
Authors: Burke Joan M , Miller James E
Published: July 2019

Genetic parasite resistance in sheep has become an important technology in the control of gastrointestinal nematodes (GIN) due to widespread anthelmintic resistant GIN. The USDA-ARS sheep flock in Booneville, AR, has been selecting for parasite resistance since 2012 through the use of estimated breeding values (EBVs) generated through the National Sheep Improvement Program (NSIP). Objective is to show value of resistance. Recently, replacement ewes (n = 69) and rams (n = 29) from the flock were offered for sale and a sale catalog with EBVs for growth, reproduction, and parasite resistance, and recent BW was available. There were 73 purchased by 13 buyers from 7 states. Of the ram lambs that sold, post-weaning fecal egg count (FEC) EBVs ranged from -29 to -100, but of the 17 ram lambs offered, only rams with values of -97 or better sold (-100 is the highest FEC EBV and values can reach > +500; the top 10% for breed are P < 0.001). For mature ewes sold, FEC EBVs ranged from 18 to -87 with higher prices offered to ewes with better FEC EBVs (P < 0.002). For all sheep, higher prices may have been offered for animals raised as multiples rather than singles (P = 0.05). Seedstock producers wishing to improve parasite resistance can benefit by using NSIP to increase resistance and sale price. The higher parasite resistance used by commercial producers will reduce the need for deworming lambs.
193 Tannins as antinutritive chemicals in red cedar
Authors: Lourencon Raquel , Hart Steven P , Gipson Terry A , Muir Jim P
Published: July 2019

Studies using goats to control red cedar (Juniperus virginiana) have shown that goats more readily consume red cedar at some locations while in other locations, they consume relatively little, but consume more during the winter. It was hypothesized that differences in red cedar intake may be caused by tannins acting as an antinutritive chemical. The purpose of this study was to characterize the levels and types of tannins in red cedar from different locations and seasons of the year. Thirty-seven samples of red cedar needles were obtained from four locations (LOC; Langston, OK; Midwest City, OK; Mannford, OK; Neosho, MO) at monthly intervals (SEA) over a 1-yr period. Needles were manually stripped from branches at approximately 1.5 m high from at least 25 plants at each location. Samples were refrigerated until analyzed for extractable condensed tannin (ECT) and total tannin (TOT) by procedure of Terrill et al. (1992). Data were analyzed by SAS GLM with main effects of LOC and SEA. ECT was significantly lower for Neosho (1.53%) than for Mannford (2.69%), Midwest City (2.79%), and Langston (2.37%), which were similar. ECT was lowest for Summer (1.76%), similar to Fall (1.85%) and both were significantly lower than for Winter (3.32%) and Spring (2.39%). TOT followed a similar pattern being highly correlated to ECT (R = 0.955; P < 0.001) and was significantly lower for Neosho (2.61%) than for Langston (3.79%), Mannford (3.81%) or OKC (4.15%). Total tannins were significantly higher in the winter (4.71%) than for the other seasons (Spring 3.64, Fall, 3.18% and Summer 2.87%). Tannins were lowest for Neosho where goats browsed red cedar most aggressively, killing >85% of the trees whereas goats killed <10% cedars at other locations. Tannins may be a significant antinutritive factor in red cedar, affecting consumption and degree of control
192 Terpenes as antinutritive chemicals in red cedar
Authors: Lourencon Raquel , Hart Steven P , Gipson Terry A , Adams Bob , Rassi Davila
Published: July 2019

At some research sites goats aggressively consumed red cedar (Juniperus virginiana) throughout the year, while at other sites goats consumed little cedar, although they consumed more cedar in winter. It was hypothesized that differences in red cedar intake may be caused by terpenes. The purpose of this study was to measure terpenes in cedar needles at different locations and times of the year. Ninety-one samples of red cedar needles were obtained from four locations (Langston, OK; Midwest City, OK; Mannford, OK; Neosho, MO) at monthly intervals over a 2-yr period. Needles were manually stripped from branches at approximately 1.5 m high from at least 25 plants at each location. Sixty grams of cedar needles were extracted by steam distillation for 2 h. Some samples were exhaustively extracted for a further 6 h to calculate recovery (45.7%). Two mL of diethyl ether were added, containing 1 mg/mL of methyl decanoate (internal standard), samples were vortexed and the ether was dried with a stream of nitrogen. Samples were subjected to gas chromatography for terpenes. The total amount of terpenes (mg/g DM) was calculated as the sum of peak areas/peak area of the internal standard x 2 mg internal standard/ 0.457/ dried weight of cedar needles. Months were categorized as season. Data were analyzed using the SAS GLM procedure with factors of season, year, and location. Neither season (P > 0.8) nor location (P > 0.25) nor the interaction (P > .9) were significant factors determining total terpene content of red cedar. Concentration of total terpenes for Langston was 20.8, Mannford 18.4, Neosho 15.2, and OKC 18.6 mg/g DM. Concentration by season was Fall 17.1, Spring 18.6, Summer 17.5, and Winter 19.7 mg/g DM. Total terpene concentration does not seem to be a factor affecting red cedar consumption by goats.
195 Sperm motion characteristics of ram semen liquid-stored in a milk egg yolk extender at four temperatures
Authors: Wildeus Stephan , O’Brien Dahlia
Published: July 2019

Varying temperatures have been used for liquid storage of ram semen and that of other species. This study evaluated motility characteristics of ram semen stored at 5, 10, 15, and 20°C for up to 96 h. Two ejaculates were collected and pooled from each of 6 rams using an artificial vagina and evaluated for motility and concentration. Samples were extended in ultra-high temperature pasteurized skim milk and egg yolk (10% v/v) containing penicillin and streptomycin, diluted to 250 million sperm/mL, and packaged in 0.5 mL straws. Semen was held at 32°C during processing, and straws placed in 500 mL jars for storage at 5°C (refrigerator), 10 and 15°C (refrigerated water bath) and 20°C (air conditioned room temperature). Cooling rates were 0.04, 0.25, 0.44, and 0.02 °C/min, and final temperatures reached after 672, 83, 36, and 567 min in the four storage environments, respectively, with cooling rates faster in a liquid than air environment. Straws from individual rams were removed at 6, 24, 48, 72 and 96 h of storage and analyzed with a computer-assisted sperm analyzer after warming to 36°C. Data were analyzed for the effect of storage time, temperature, and their interaction on sperm motion characteristics. Sperm motion characteristics were not affected over time during storage at 5 and 10°C. At 15°C motility parameters decreased in a curvilinear (P < 0.05) relationship with time (progressive motility: 52.6 to 29.7%; rapid motility: 36.5 to 16.5%), and at 20°C in linear (P < 0.001) relationship (progressive motility: 51.9 to 13.1%; rapid motility: 36.1 to 6.3%). Circular motility decreased (P < 0.05) with increasing temperatures after 72 and 96 h of storage, while local motility was not affected by storage temperature and time. Results suggest storage at 10°C may be a viable alternative to storage at 5°C as retention of motility was similar.
197 Utilization of Katahdin rams with lower fecal egg count estimated breeding values improves parasite resistance and fitness traits of progeny
Authors: Weaver Andrew R , Wright Donald L , Greiner Scott P , Bowdridge Scott A
Published: July 2019

Genetic selection for internal parasite resistance in sheep is a valuable tool to mitigate effects of parasitism especially when significant within breed variability exists. To better understand the mechanism underpinning this variability, a divergent mating scheme was established. Katahdin rams (n = 4) were selected based on their estimated breeding value (EBV) for fecal egg count (FEC) and grouped as numerically high (HiFEC; n = 2) or low (LoFEC; n = 2). Rams were randomly mated to Katahdin ewes at the Southwest Virginia Agriculture Research and Extension Center. Lambs were born mid-March and managed as one group, then weaned in mid-June. Lambs were transported to the WVU Animal Sciences Farm where they were randomly allocated to four pens with even distribution of sire and sex. All lambs (n = 109) were infected with 10,000 H. contortus L3 and the infection persisted for 5 weeks. Weights, FEC, and packed cell volume (PCV) were collected weekly. Statistical analysis was performed using the Mixed Model procedure and repeated measures in SAS with fixed effects of sire group. Weaning FEC was numerically greater for HiFEC-sired lambs vs. LoFEC-sired lambs (2914 vs. 1821 eggs/g; respectively). However, death loss for HiFEC-sired lambs tended to be almost twice that of LoFEC-sired lambs (20% vs. 11%, P = 0.09; respectively). Weaning weights did not differ. Fecal egg count from the prepatent to patent period was greater in HiFEC vs. LoFEC-sired lambs (210 vs. 34 eggs/g; P = 0.05). Packed cell volume was numerically lower in HiFEC-sired lambs. There were no differences in post-weaning growth, ultrasound fat thickness, or loin depth in lambs from divergent sire groups. These data indicate that utilizing LoFEC EBV sires reduces FEC and improves disease resistance in progeny without affecting growth or carcass traits
136 Reflections on the foundational scientific knowledge of undergraduate animal science students: a three-year study
Authors: Thomas Lauren R , Powell Jeremy G , Kegley Elizabeth B , Jogan Kathleen
Published: July 2019

In 2015, the University of Arkansas Department of Animal Science developed a strategy for assessing student-learning outcomes within its undergraduate teaching program. The first recognized outcome states that students will demonstrate foundational scientific knowledge in the general animal science disciplines of physiology, genetics, nutrition, muscle foods, and production animal management. Subsequently, a 58-item assessment tool was developed for direct assessment of student knowledge—focusing primarily on freshmen and senior students. Over the past 3 academic calendar years, 381 students (196 freshmen, 48 sophomores, 19 juniors, 113 seniors, 5 graduates) were assessed, either during an introduction to animal science course or by appointment with outgoing seniors majoring in animal science. Scores were categorized using demographic data collected at the beginning of the assessment tool. Comparison categories included academic class, major, and general student background (rural or urban). Data analysis were performed using the Glimmix procedure of SAS, with student serving as the experimental unit and significance set at P ≤ 0.05. Generally speaking, animal science majors performed better (P < 0.01) than students from other majors, and students with a rural background performed better (P < 0.01) than their urban-backgrounded peers. Overall, senior assessment scores averaged 23-percentage points greater (P < 0.01) than freshmen assessment scores, and the average scores for freshmen and seniors were 43% and 66% respectively. In regards to student performance within each discipline, there was an average improvement of 24 percentage points between freshmen and seniors in all of the measured disciplines except for muscle foods, which only saw a 10-percentage point improvement between the two classes. While the overall improvement in scores is indicative of increased student knowledge, the department would like to see greater improvement in all discipline scores for seniors majoring in animal science.
135 Developing foundational courses to support undergraduate student success in animal science departmental core curriculum
Authors: Dunlap Kathrin A , Early Lonisa , Fowler Debra , Wickersham Tryon A
Published: July 2019

Today’s student population comes from highly diverse cultural and socio-economic backgrounds, entering college with a range of life experiences and professional aspirations. The selection of and success upon entering a major is highly influenced by those factors. As society has progressed, the principle purposes of the animal science discipline have remained intact, but the industry scope has expanded as has the range of background knowledge and experience of students entering the major. To address these changes a data-driven, student-centered curriculum study was conducted. Stakeholder (comprised of industry members, faculty, current and former students) surveys (n = 289) served as a foundational component of the study. Survey responses revealed the existence of a gap between student knowledge and skills and faculty expectations upon entering disciplinary core courses, which were deemed necessary to gain proficiency in areas identified by industry stakeholders. To address that gap, collaborative efforts between Animal Science Department faculty and members of the University Center for Teaching Excellence, as well as findings from the data generated as part of the curriculum redesign process, were used to identify two new courses for development: Farm Animal Biosystems and Livestock Production Systems. Each course incorporates departmental learning outcomes, assessments, and specified teaching methods into their syllabi. Furthermore, they illustrate a novel approach to addressing the disparity in student background knowledge and skills. Rather than assuming a standardized level of skill and addressing only gaps in knowledge or vice versa, key areas have been identified and separated for individualized focus in order to provide students with a solid foundation in both the scientific and applied components of the discipline. Successful completion of these courses will enable students to enter the specialized disciplinary core classes with a more uniform knowledge base, thus promoting success throughout the curriculum
137 Impact of Career Development Events on motivation to major in animal science
Authors: Chumbley Steven , Russell Mark R , Garza Sarah
Published: July 2019

Previous research has shown that motivated youth typically select activities that incorporate existing interests and may influence their career choices. Involvement in the National FFA provides opportunities for youth to develop skills and knowledge through events known as Career Development Events (CDEs). These events are designed to motivate students and encourage leadership and career development. The purpose of this study was to determine the impact of participation in CDEs on student motivation and preparation to major in animal science. The study was guided by a researcher-developed instrument, measuring motivation and preparation on a Likert-type scale of 1–5. The sample population was junior (13%) and senior (87%) animal science majors at a southern Hispanic serving institution, enrolled within an advanced animal nutrition course. The instrument had a Cronbach’s alpha posttest reliability of .883, with inter-reliability of .610 for preparation and .887 for motivation. The sample population consisted of 24 students, of which 50% identified as Hispanic and 31% as Caucasian. Out of the 24, 16 had participated in CDEs, resulting in a response rate of 67%.The overall mean scores for motivation were 3.85 (SD= 1.20) and 3.79 (SD = 0.72) for preparation (Scale of 1–5). The highest mean scores were found within the motivation statements, “Competing in CDEs influenced my decision to major in animal science” (M = 4.0) and “Competing in CDEs motivated me to attend college” (M = 3.94). The highest scores for preparation were found within the statement “Competing in CDEs prepared me to be successful in my chosen career” (M = 4.13). Females were found to have higher mean scores overall, with students identifying as Caucasian having a higher mean score over Hispanic students and Seniors scoring slightly higher. Overall the scores were moderate and showed a need for continued study in this area.
56 The efficacy of extended-release eprinomectin for the reduction of horn flies, face flies, and fecal egg counts of parasitic nematodes in replacement beef heifers
Authors: Landers Sophia F , Tucker Christopher , Powell Jeremy G , Wray Eva , Cauble Reagan , Lester Toby D
Published: July 2019

The purpose of this study was to evaluate the efficacy of extended-release eprinomectin against horn flies, face flies, and fecal egg counts of parasitic nematodes in crossbreed replacement beef heifers. Fifty-four heifers were randomly placed into three treatment groups (n = 18 heifers/treatment). Group 1 was administered the labeled dosage of extended-release eprinomectin at the onset of fly season (day 0). Group 2 acted as the negative control. Group 3 received the anthelmintic injection once a quarter of the heifers in the group reached the threshold treatment level for horn flies (n = 200 flies/animal; day 41). All cattle were separately pastured for the duration of the study. Throughout the study, nematode infections were measured via fecal egg counts while horn and face flies were visually monitored. Evaluation of pregnancy status was recorded at the conclusion of the study (day 144). Due to the high number of face flies, heifers were treated with insecticide dusts twice during the study (day 54 and 69). Group 1 averaged a fecal egg count of (2.3), group 2 (7.4), and group 3 (9.1) (day 111). Low egg counts for all treatment groups reflected minimal parasite burden which likely had little effect on treatment groups. Extended release eprinomectin had little influence on face flies given that all groups were above threshold at days 40, 48, and 54. At study conclusion, horn fly population was lower (P < 0.05) for group 1 (405.6) compared to group 2 (680.6) and group 3 (680.6). Conception rates were greater (P < 0.05) in group 1 (89%) compared to the control heifers (56%) and group 3 exhibited an intermediate rate (72%). Results indicate that although treatment with extended-release eprinomectin did not decrease the face fly burdens, it did have an effect on fecal egg counts, horn fly burdens, and subsequent pregnancy status at the conclusion of the study
48 Impact of weaning strategy on beef cow performance
Authors: Worthington Mary Clarke , Ott Grace C , Poore Matthew H , Pickworth Carrie L
Published: July 2019

It has been shown that physiologic stress in beef cattle can impact animal performance. Weaning stress is recognized as a major stress in a calf’s life. However, less is known of its impacts on the dam or developing fetus, as the dam is at the end of the second trimester at weaning. Therefore, the objective was to investigate the impact of weaning stress on cow performance. A total of 240 cows from two locations were assigned to one of three weaning strategies: abrupt removal of the calf on d 0 (n = 80), d 7 cow-calf fenceline contact (n = 81), and late weaning on d 84 (n = 79). Cows averaged 16 and 24 weeks of gestation on d 0 and d 84 respectively. Weights and BCS were obtained monthly. Behavioral observations occurred over the week before and after weaning for each weaning period. Five late-wean cows per location were milked on d 14 and d 70 to estimate milk yield throughout the late wean period. Data were analyzed using the MIXED procedure of SAS with BW and BCS utilizing repeated measures. Means are declared different at P ≤ 0.05. The ADG over the course of the study was lower (P < 0.05) for the late weaned cows compared to the abrupt weaned cows. This was also reflected by change in body condition where late weaned cows dropped from a 5.7 to a 4.9 (P < 0.05) over the 105 d. Milk production in late weaned cows decreased over time (6.0 and 4.4 kg/d for d 14 and 70, respectively; P = 0.05). Energy expenditure for lactation may have contributed to the drop in BCS of the late weaned compared with the non-lactating cows and could compromise third trimester growth of calf in utero. The results of this study warrant further exploration of the effect of weaning stress on dams and their developing fetuses.
46 Species-specificity in metmyoglobin reduction
Authors: Bechtold Emily , Suman Surendranath , Mohanty Smita , Mazumder Suman , Krishnan Sadagopan , Nerimetla Raja
Published: July 2019

Myoglobin is the primary sarcoplasmic protein responsible for meat color. Previous research has reported that myoglobin oxidation is species-specific. Metmyoglobin reducing activity is an inherent property to limit myoglobin oxidation. However, limited research has determined species specificity in metmyoglobin reducing properties. The objective of current study was to compare metmyoglobin reducing properties of eight different species such as beef, porcine, bison, deer, emu, equine, goat, and sheep in vitro. Myoglobin was isolated from eight different species via ammonium sulfate precipitation. The pH of the myoglobin was adjusted by passing through a column pre-calibrated with 50 mM phosphate buffer at pH 5.6. All species myoglobin were converted to metmyoglobin, and the metmyoglobin reduction was determined by two different approaches, non-enzymatic metmyoglobin reducing activity (NMRA) and oxidation-reduction potential (ORP). In the first method, NADH (electron donor), EDTA, and methylene blue (electron carrier), were added in a cuvette and increase in absorbance at 582 nm was monitored using a UV-Vis spectrophotometer. In the second method, the ability of the heme to get reduced was determined using an RedoxSys analyzer, in which electron was directly transferred to heme. The NMRA and ORP experiments were replicated five times. The data were analyzed using the Mixed Procedure of SAS, with species as the fixed effect. There were species-specific differences (P < 0.05) in NMRA and ORP. Bovine myoglobin had the greatest (P < 0.05) NMRA compared with sheep, equine, goat, deer, bison, pork, and emu. There were no differences (P > 0.05) in NMRA among equine, goat, deer, bison, pork, and emu. ORP studies indicated that beef and porcine myoglobins had the greatest ability to get reduced (P < 0.05) compared with other species. Hence, use of different techniques and approaches will help to elucidate the mechanistic basis of metmyoglobin reduction.
54 Digestibility of forages in ruminally cannulated Jersey steers supplemented with liquid glycerol on a wheat straw forage diet
Authors: Soto Itzel A , Boyd Jamie
Published: July 2019

The purpose of this study was to determine the impact of supplementation of glycerol at a rate of 15% of DMI on forage digestibility on a diet of mature wheat hay. Forages tested included bermuda hay, wheat hay, alfalfa hay, and sorghum sudan hay. Samples were ground through a 2mm screen and placed in Ankom forage in-situ bags. Samples were run in triplicate to reduce error and increase statistical significance. Two ruminally cannulated steers were used in a 2x2 Latin square design for the study with ad libitum access to wheat hay and water. Animals were housed in a dry lot pen for the study. Diets offered were Control = wheat hay and Treatment= control + glycerol at 15% of daily DMI. The study consisted of 2 three-week periods. Each period had a 2-week standardization followed by a 1-week test period. During the test period, forage bags were placed in each steer for 0 h, 48 h, 72 h, 96 h, and 144 h for fermentation. At the end of the incubation period, bags were collected and cold shocked to stop microbial digestion. The samples were then dried at 55°C and stored for later analysis for NDF. A significant impact on NDFdig by treatment (P < 0.0001) was observed. NDFdig was 59.2% w/ glycerol versus control at 49.13% overall. In addition, there was a significant difference between steers (P = 0.0001) on glycerol treatment (51.95% versus 66.45% NDFdig between steer A and B), indicating difference in ruminal population efficiency between individual animals. No significant difference (P = 0.98) between steers on the control treatment was observed. Implications of this study are the inclusion of dietary glycerol in the diet of ruminants on a low-quality forage diet may increase energy level and improve ruminal digestibility and animal response may be dependent on the unique ruminal environment of individual animals.
52 Timing of progesterone exposure effects pregnancy rates following fixed timed artificial insemination in postpartum beef cows
Authors: Smith Anna L , Poole Rebecca K , Mayberry Kyle , Newsome McKayla A , Dudley Harrison B , Poole Daniel H
Published: July 2019

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.
5 Effect of feeding time on behavioral and stress responses in gestation sows under isocaloric conditions
Authors: Manu Hayford , Lee S H , Huang Q , Pangeni D , Keyes M C , Cairns J , Baidoo S K
Published: July 2019

Investigated the effect of feeding time on behavior and stress responses in pregnant sows under isocaloric conditions. Eighteen sows (Landrace × Yorkshire); BW 248.6 ± 2.8 kg; parity 3.30 ± 0.39); were blocked by parity and randomly assigned to 1 of 3 feeding times. Corn-soybean meal-based diet was fed once at: 0730 (Control, T1), 1130 (T2), and 1530 h (T3). On average, sows received 7190 kcal ME d−1 during gestation from 2.25 kg of diet formulated to contain SID Lys/ME of 1.71 g/Mcal. Saliva samples were collected every 2 h for 12 h in stalls on d 52 of pregnancy and assayed for cortisol using ELISA technique. Behavior data were collected 24 h for 7 d from d 53 of gestation by affixing a Remote Insights ear tag to each sow after 21 d adaptation period. Each sow had 120,960 data points categorized into: “Active,” “Feed” or “Dormant”. Data were analyzed using GLIMMIX procedure of SAS 9.4. Statistical significance was set at P ≤ 0.05, and a trend as 0.05 < P ≤ 0.10. Sow was the experimental unit. A 24 h area under the curve (AUC) was estimated by trapezoidal summation method. Adjustment for multiple comparisons was based on Tukey Kramer’s method. Sows fed daily at 0730 had both lower feeding and total activity compared with sows fed at 1130 h (P < 0.02) but similar to sows fed at 1530 h (P > 0.05). Feeding sows at 1130 h daily resulted in reduced cortisol AUC compared with 1530 h fed sows (P < 0.04) but similar to sows fed at 0730 h (P > 0.05). In conclusion, feeding sows daily at 1130 resulted in increased feed and total activity but reduced cortisol concentration, suggesting that elevated sow activity might not necessary indicate activation of hypothalamic-pituitary-adrenal (HPA) axis.
11 Use of pressure mat gait analysis in measuring pain following normal parturition in dairy cows
Authors: Kleinhenz Michael , Gorden Patrick , Burchard Michael , Ydstie Joshua , Coetzee Johann
Published: July 2019

Research investigating the pain of normal parturition is lacking as there are few objective methods for measuring pain. The objective of this research was to describe the gait of cows following eutocia using pressure-mat gait analysis; and determine if meloxicam alters the gait of cows. Twenty Holstein cows within 26 h of unassisted calving were enrolled into the study. Treatment groups included: 1) post-partum cows administered meloxicam (MEL; n = 10); and 2) post-partum cows administered placebo (PLBO; n = 10). Meloxicam was administered by oral bolus at 1 mg/kg within 26 hours of calving. Placebo cows were given an oral bolus of dry whey powder within 26 hours of calving. A commercially available floor mat-based pressure/force measurement system was used to compare ambulation between treatment groups. Cows were walked across the mat before treatment administration, and 2, 4, 6, 8, 12, 24, 48 and 72 hrs post-treatment. The percent of total force, percent total contact pressure, and percent total impulse of the rear limbs was calculated. Outcome measures were statistically analyzed using repeated measures, with the cow serving as the experimental unit. Cows in the MEL group placed 48.9% (95% CI: 47.4 – 50.5%) of total force on the rear limbs compared to 46.3% (95% CI: 44.7 – 47.9%) in PLBO cows (P = 0.02). Total impulse on their rear limbs for the MEL cows was 50.5% (95% CI: 48.6 – 52.4%) compared to 46.7% (95% CI: 44.8 – 48.7%) for the PLBO cows (P = 0.01). No differences in contact pressure of the rear limbs was observed (P = 0.27). The PLBO cows had a longer gait 101.3 cm (95% CI: 95.9 – 106.6 cm) versus 90.8 cm (95% CI: 85.4 – 96.1 cm) (P = 0.03). These findings show meloxicam treated cows have altered weight distribution to the rear limbs as measured by pressure mat gait analysis, suggesting meloxicam may effectively treat post-partum pain.
12 A multimodal approach for piglet pain management after tail docking
Authors: Viscardi Abbie V , Turner Patricia
Published: July 2019

Millions of piglets on commercial production farms are tail docked each year to reduce the incidence of tail biting. While this procedure is known to be painful, piglets in the United States are often not provided analgesia or anesthesia for pain relief. The objectives of this study were to assess a multimodal approach to managing tail docking pain in piglets, using 0.4 mg/kg meloxicam (MEL), 0.04 mg/kg buprenorphine (BUP), and Maxilene® (MAX). The effectiveness of each drug and drug combination was evaluated using behavioral indicators, vocalization, and facial grimace analysis. This study also assessed whether male and female piglets responded differently to pain or pain treatments. Four-day-old piglets from 14 litters (n = 165 total) were used and piglets within a litter were randomly assigned to one of six possible treatments: MEL, BUP, MEL + BUP, MEL + BUP + MAX, no treatment (tail docked control), or sham (non-tail docked control). Treatments were administered intramuscularly (MEL, BUP) or topically on the tail (MAX) 20 min prior to tail docking. Piglets administered MEL + BUP and BUP demonstrated significantly fewer pain behaviors than piglets in the MEL and no treatment group (p < 0.05). MEL + BUP + MAX and BUP piglets also grimaced significantly less than piglets in the no treatment group (p < 0.05). There were no significant differences in emitted vocalizations between the analgesia-treated piglets and the no treatment group, and both injection and tail docking elicited piglet vocalizations of similar frequency, power, and energy (P > 0.05). There were no significant differences in behavior, facial grimacing or emitted vocalizations between male and female piglets. All treatment groups with buprenorphine were able to alleviate tail docking-associated pain, suggesting that opioid administration is highly effective for managing piglet pain.
13 Effect of housing cow-calf pairs on dry lots vs pasture on calf performance and behavior
Authors: Neira Lucas T , Cooney Ashley E , Chapple Wesley P , Meteer William T , Shike Daniel W
Published: July 2019

The objectives were to analyze the effects of housing cow-calf pairs in dry lots (DL) or pasture (PAST) on calf performance and behavior through the receiving phase. Simmental × Angus (n = 108; 87 ± 11.5 d postpartum) spring-calving cows were stratified by age, BW, BCS, and calf sex and allotted to six groups. Cows were limit-fed a ration consisting of corn silage, dried distillers grain, corn stalks, dry rolled corn (DRC), and soybean hulls to meet protein and energy requirements. Calves had ad libitum access to same diet in an adjacent pen. Calves on PAST were rotationally grazed with free-choice mineral. After weaning (177 ± 11.5 d of age) all calves were fed a diet consisting of corn silage, wet distiller grains, DRC, and grass hay during the receiving phase (42 d). At the age 87, 142, 177, 198, and 219 ± 11.5 d, BW was measured. Hair coat score (HCS) and dirt score (DS) were measured on d 0 and d 90. Calf behavior was observed after feedlot arrival. Average daily gain, DMI and feed efficiency were also analyzed. The data were analyzed using the MIXED procedure of SAS. Dry-lot calves had greater (P < 0.01) BW and ADG prior to weaning. Calves from PAST had lower (P < 0.01) DS and greater (P < 0.01) HCS at weaning. Upon feedlot arrival, more (P < 0.01) DL calves were walking and had increased (P < 0.01) vocalizations. Calves from PAST had greater (P < 0.01) ADG, DMI as a percent of BW, and gain:feed than DL calves during the receiving phase. Calves raised in a dry lot had greater BW and ADG prior to weaning, but PAST calves had fewer behavioral signs of stress and greater growth performance in feedlot.
21 Issues of sow lifetime productivity from an international perspective: from research to production level
Authors: Bortolozzo Fernando , Ulguim Rafael , Mellagi Ana Paula , Mallmann Andre L , Bernardi Mari
Published: July 2019

Sow longevity is defined as the time elapsed from gilt entry into the breeding herd until her removal as a result of culling or death. Increasing herd retention rate is important to improve sow lifetime productivity. Higher removal rate implies an increase in the percentage of young females in the herd, a category with lower production potential and a higher risk of early culling. Systematic gilt replacement is required for genetic gain, but it is essential to achieve a retention rate that allows the sows to reach their maximum production potential in the later parities. In this way, it is important to evaluate the reasons for removal and death in order to establish strategies for reducing involuntary culling and controlling mortality rate. Although reproductive failures persist as the main culling cause, its expressivity has been apparently reduced. To improve sow retention rate, management intervention should start during gestation with a focus on improving the replacement gilt’s weight at birth. Ensuring adequate colostrum intake is critical for achieving targeted pre-wean and post-wean growth rate. In addition, approaches that improve gilt body development during the post-weaning phase and up to first breeding are key steps to reducing culling for structural problems and low reproductive performance. In this sense, the use of gilt development units allows a regulated flow of replacement gilts that meet the required parameters recommended by the different genetic suppliers. Because locomotor disorders are frequent reasons for early culling, inspection and maintenance of the animal facilities should be prioritized in all phases of rearing gilts and sows. The opportunity to reduce sow mortality, culling for poor reproduction, and structural failure resides in the ability to translate new research discoveries on gilt birthweight, growth, and body measures into improved lifetime pig production to the 3rd parity.
19 Overview of the National Pork Board replacement gilt feet and leg evaluation trial
Authors: Stock Joseph D , Supakorn China , Calderon Diaz Julia A , Rothschild Max F , Stalder Kenneth J
Published: July 2019

Replacement gilt feet and leg conformation traits are subjectively evaluated at early ages (150 d) in order to select acceptable replacements. The objectives of this study were to: 1) evaluate replacement gilt feet and leg conformation (FLC) using subjective and objective measurement methods, 2) estimate objective joint angle changes over two parities, and 3) evaluate the effect of three diets differing in standardized ileal digestible (SID) lysine concentrations on FLC traits using the objective evaluation method. Crossbred Large White × Landrace gilts (n = 641) were used. Gilts were moved to GDU at 77 days-of-age and randomly allotted to three ad libitum fed dietary treatments providing similar ME but differing in SID lysine concentrations (low, medium, and high) during the grow-finisher period. All animals received common gestation and lactation diets. Feet and leg conformation traits were evaluated at 100 d, 200 d, 1st litter (392 ± 25 d) and 2nd litter (548 ± 49 d) weaning events. Subjective evaluation was done on a scale from 1 to 5. Data were analyzed using mixed linear model methods. The majority of gilts received the intermediate score (i.e. 3) when joint angles were subjectively evaluated. No differences (P ≥ 0.05) were observed for knee, front pastern and hock objective joint angles between subjective scores assigned. Differences in subjectively evaluated rear pastern (P < 0.05) were observed, where objective joint angles associated with scores of ≤ 2 and 3 were lower than score of ≥ 4. There was no interaction between dietary treatment and objective evaluation time-period for any FLC traits studied (P > 0.05). Females with greater knee, hock, front and rear pastern objective joint angles at 100 d of age, continued to have greater joint angles (0.2 ± 0.04 degrees; P < 0.001) later in life. Front and rear pastern joint angles decreased (P < 0.001) and hock joint angles increased from 100 d to end of study (P < 0.001).
32 Functional annotation of livestock genomes: chromatin structure and regulation of gene expression
Authors: Foissac Sylvain , Djebali Sarah , Munyard Kylie , Vialaneix Nathalie , Rau Andrea , Acloque Herve , Lagarrigue Sandrine , Giuffra Elisabetta
Published: July 2019

Improving the functional annotation of animal genomes is a key challenge in bridging the gap between genotype and phenotype, thus enabling predictive biology. Regarding livestock production, major outcomes are expected from a better understanding of the genetic architecture underlying quantitative traits. As part of the Functional Annotation of ANimal Genomes action (FAANG: www.faang.org), the FR-AgENCODE project generated omics data to improve the reference annotation of the cattle, pig, goat and chicken genome. High-throughput molecular assays have been performed on tissues/cells relevant to immune and metabolic traits. From two males and two females per species (pig, cattle, goat, chicken), strand-oriented RNA-seq gene expression and ATAC-seq chromatin accessibility assays were performed on liver and two PBMC-sorted T-cell types (CD4+ and CD8+). Chromosome Conformation Capture (in situ Hi-C) was also carried out on liver samples. About 4,000 samples have been collected at the INRA biorepository and registered at the EBI BioSamples registry. More than 80% of the planned experiments could be completed, generating ~11.5 billions of sequencing reads over the 3 assays. While most (50–80%) RNA-seq reads mapped to annotated exons, thousands of novel transcripts were found, with ~60K mRNAs and ~22K lncRNAs in cattle. Differentially expressed genes between cell types were enriched for immunity- or metabolism-related terms, and differentially accessible chromatin regions were identified as potential regulatory sites. Interestingly, correlations between gene expression and promoter accessibility across samples were skewed towards both positive and negative values, suggesting distinct regulatory mechanisms of gene expression. These patterns have been further investigated using human data from the Epigenome Roadmap Mapping Consortium. Altogether, this study illustrates the interest of a coordinated effort to tackle the genome-to-phenome challenge and provides a useful resource to the community. Availability: www.fragencode.org.
35 Applying GGP-F250 genotypes to elucidate the biochemical basis for animal variation in meat quality attributes
Authors: King Andy , Shackelford Steven , Wheeler Tommy
Published: July 2019

Understanding the biological factors regulating animal variation in meat quality traits continues to challenge meat scientists. Meat scientists have studied the impacts of numerous intrinsic and extrinsic variables on meat quality traits. Often, component traits, known to directly contribute to the trait of interest, have been utilized to determine the mechanisms by which these impacts are made. However, only a limited amount of the variation in these traits is explained by component traits, indicating that a significant knowledge gap exists. The rise of genotyping assays for functional alleles provides an opportunity to further understanding of the biological basis of meat quality traits. For example, lean color is the primary factor utilized by consumers in making purchasing decisions. Cuts from some carcasses discolor rapidly and must be discounted or discarded. Component traits (reducing ability and oxygen consumption) generally explains a total 30 to 40% of the variation in lean color stability. A genome-wide association study (GWAS) was conducted using GGP-F250 genotypes from 2,476 steers representing crosses of 18 beef breeds that had been phenotyped for lean color change during simulated retail display. The GWAS identified 417 single nucleotide polymorphisms (SNP) explaining the heritable variation (0.45). Identified genes included genes coding for reductases and cytochromes as well as mitochondrial genes, which are consistent with conventional wisdom regarding lean color stability. However, other genes identified are related to muscle contraction, action potential mediation, calcium binding, actin binding, stress response, and apotosis. In addition, gene ontology analysis indicates 128 genes contributing to metabolic processes, with 74 being associated with nucleobase containing compound metabolic processes. Thus, these results suggest novel mechanisms, which have not been previously studied in detail in relation to lean color stability. This approach provides a means to increase understanding of the biological regulation of meat quality traits.
36 A large multi-breed reference panel and maximizes genotype imputation accuracy in cattle
Authors: Rowan Troy , Hoff Jesse L , Crum Tamar , Taylor Jerry F , Schnabel Robert , Decker Jared E
Published: July 2019

The use of array-based SNP genotyping in the beef and dairy industries has produced an astounding amount of medium-to-low density genomic data in the last decade. While low-density assays work exceptionally well in the context of genomic prediction, they are less useful in mapping and causal variant discovery. This project focuses on maximizing imputation accuracies to the marker set of two high-density research assays, the Illumina Bovine HD, and the GGP-F250 which contains a large proportion of rare and potentially functional variants (~850,000 total SNPs). This 850K SNP set is well-suited for both imputation to sequence-level genotypes and direct downstream analysis. For testing, 310 animals from multiple breeds, all with observed HD and F250 genotypes, were downsampled to various commercial chip densities ranging from 8K–130K markers. We use both well-established and novel measures of imputation accuracy to categorize precisely where, why, and how imputation errors are made. These metrics provide insights into downstream interpretation and identify situations where caution should be exercised when analyzing imputed variants. We find that a large multi-breed composite imputation reference comprised of 36,131 samples with either HD and F250 genotypes significantly increases imputation accuracy compared to a standard within-breed reference panel, particularly at low minor allele frequencies. Breed composition information for each animal in our testing panel allowed us to identify how a breed’s representation in the reference panel affects the imputation accuracy of both purebred and admixed animals. Starting chip density also impacts imputation accuracy, but gains appear to plateau at around 50,000 markers. The addition of the F250’s rare variation to the reference panel increased the imputation accuracy of rare variants from the HD assay by an average of 4.32%. We expect this low MAF content from the F250 to have a similar positive impact on rare variant imputation at the sequence level. Early work using 850K imputed data in genomic predictions has shown substantial increases in both chip heritability and prediction accuracies. Using a large multi-breed reference and the best practices identified through this work will maximize imputation accuracies in virtually all cattle populations, particularly ones that are highly admixed with little or no available pedigree information.