bluuebunny/crossref_metadata_2025 huggingface dataset:
PSIII-4 Exploring the behavioral effects of glycerol supplementation in ruminally cannulated cows grazing wheat pasture
Authors: Campa-Madrid Sara E , Carrera Vinicio , Lucero Naomi , Ropp Kate E , Funk Micah , Perea Andres Ricardo , Spetter Maximiliano J , Soto-Navarro Sergio A
Published: September 2024

Energy intake and metabolism have a key role in the control of dry matter intake (DMI), fermentation processes, and grazing behavior of beef cattle, and is likely affected by intertwined relationships between forage availability and stage of maturity, offering of energy supplements and climate- and animal-related factors. Ruminally cannulated mixed-breed nonlactating cows [n = 9; initial body weight (BW) = 564.4 ± 101.6 kg] grazing wheat pasture were used in a split-plot design with the objectives of evaluating the effects crude glycerine supplementation and forage maturity on grazing behavior. Treatment was the main plot, and stage of forage maturity was the subplot. Treatments were unsupplemented control (CON) and crude glycerine supplementation (SUP). Crude glycerol (37.2% glycerol, DM basis) was offered at 0.11% of BW (DM basis) and dosed intraruminally via rumen cannula at 0700 and 1900 h daily. The stages of wheat pasture maturity were March (MAR; vegetative stage) and April (APR; early reproductive stage). All cows were fitted with LoRa WAN tracking collars, housing GPS and triaxial accelerometers and allowing real-time inspection of cow position and activity data through time. Hourly (d 10 and 23) and daily change of walking distance (m), activity index and budget for grazing, resting, and walking time (min) were analyzed with a repeated measure mixed model for the split-plot design. Walking distance (1,200 ± 13 m), activity index (10,006 ± 122), resting time (607 ± 5 min), grazing time (662 ± 8 min) and walking time (171 ± 8 min) were not affected (P ≥ 0.52) by crude glycerine supplementation or by stage of forage maturity (P ≥ 0.07), but varied (P < 0.001) by day and by hour of day, likely indicating circadian effects on meal frequency and duration associated with the hour of the day and forage depletion through time. Grazing behavior was more likely affected by climate, pasture, animal, and management variables and less affected by GLY dose. Results indicate that crude glycerine may be used in supplements for cattle grazing wheat pasture to increase energy intake and without adversely creating associative or substitution effects, grazing behavior or sacrificing pasture utilization.
PSIII-5 Characteristics of in-vitro digestibility of forage selected by cattle supplemented with crude glycerin while grazing wheat pasture
Authors: Carrera Vinicio , Campa-Madrid Sara E , Lucero Naomi , Ropp Kate E , Soto-Navarro Sergio A
Published: September 2024

Ruminally cannulated mix-breed cows (n = 9) were used in a split-plot design with the objective of evaluating the effects of crude glycerin supplementation on in-vitro rate of digestibility. Treatments were unsupplemented control (CON); and crude glycerin supplementation [SUP; 37.2% glycerin, dry matter (DM) basis] fed at 5% of expected forage intake (2.2% of BW). The wheat maturity stages occurred between mid-March (MAR) and early April (APR) representing the vegetative and early reproductive stage, respectively. Cows grazed in a single wheat pasture with supplements offered at 0700 and 1900 h daily. Each stage consisted of 13 d of adaptation to wheat pasture and SUP. On d 14 at 1200 h, cows were ruminally evacuated and allowed to graze for 60 min. Subsequently, grazed material obtained directly from the rumen via rumen cannula was incubated for 0, 3, 6, 12, 24, and 36 h in a Daisy incubator to estimate rate of in-vitro digestibility. Rate of digestibility was estimated using a non-linear regression of digestibility vs. time of incubation. A supplement × forage maturity interaction (P = 0.05) for in-vitro DM digestibility was detected. During MAR, in-vitro DM digestibility of forage was greater (P = 0.01) for masticates of SUP compared with CON fed cows (53.3 and 49.2 ± 1.97). However, during APR, in-vitro DM digestibility of forage was not affected (P = 0.86) by supplementation (42.7 and 44.8 ± 1.97). Rate of in-vitro DM digestibility of forage was greater (P = 0.04) for SUP than CON cows (2.43 and 4.53 ± 0.667). In-vitro digestibility and rate of digestibility of forage NDF were not affected by crude glycerin supplementation (P ≥ 0.13) or forage stage of maturity (P ≥ 0.10). Results indicate that crude glycerin can be added to supplement of cattle grazing wheat pasture to increase energy intake without negative impacts on characteristics of in-vitro digestibility, especially when introduced during the initial phase of wheat pasture maturity.
PSIII-11 Long-term effects of intra-articular lipopolysaccharide on markers of inflammation and cartilage metabolism in young Quarter Horses
Authors: Gualandri Cecilia R , Leatherwood Jessica L , Paris Brittany L , Moore Grace E , Pavel Lauren R , Arnold Carolyn E , Glass Kati G , Linne Paige K , Carter Maggie M , George James M , Martinez Rafael E , Wickersham Tryon A , Bradbery Amanda N
Published: September 2024

Intra-articular lipopolysaccharide (LPS) is an established model for inducing robust, transient inflammation and increasing cartilage metabolism for up to 24 h following administration. Currently, there is limited information evaluating the long-term effects of this gram-negative endotoxin on the intra-articular environment of young horses. Therefore, the objective of this study was to determine the lasting effects of a single administration of intra-articular LPS on synovial biomarkers of inflammation and cartilage metabolism over 35 wk. Quarter Horse yearlings [n = 10; body weight (BW) = 409 ± 24 kg; 619 ± 16 d of age; fillies, (n = 7) and geldings (n = 3), originating from a single herd were used to test the hypothesis that intra-articular inflammation and cartilage metabolism would not be elevated at 35 wk post-injection. Each horse had one randomly selected radiocarpal joint injected with 0.8 mL of a 0.5 ng LPS solution derived from Escherichia coli O55:B5 (INFL; Sigma-Aldrich, St. Louis, MO) and the contralateral joint received sterile lactated Ringer’s solution (CON) as a control. Synovial fluid was obtained on 0 (before injection of LPS), 2, and 35 wk following arthrocentesis. Synovial fluid samples were analyzed in duplicate for carboxypropeptide of type II collagen (CPII), collagenase cleavage neopeptide (C2C), chondroitin sulfate 846 epitope (CS846), and prostaglandin E2 (PGE2) by commercial ELISA (IBEX Pharm, Montreal, Quebec, CA and Arbor Assays, Ann Arbor, MI). Biomarkers were analyzed using PROC MIXED of SAS v9.4 with repeated measures (time). The model included treatment (CON, INFL), time (week), and treatment × time interaction as fixed effects. Synovial biomarkers PGE2, CPII, and CS846 changed over time (P < 0.01) regardless of LPS administration, increasing from 0 to 2 wk and declining to below baseline concentrations at wk 35. There was a treatment × time interaction (P ≤ 0.01) in which INFL joints had decreased catabolic C2C concentrations compared with CON joints at wk 35. Therefore, LPS administration did not increase cartilage metabolism and inflammation levels at 2 or 35 wk post-LPS induction, indicating no negative effects compared with the contralateral controls. This study supports using intra-articular LPS in young horses without negative long-term effects.
PSIII-14 Cotton gin byproduct in growing diets for beef steers
Authors: Huggins Michael J , Poore Matt H , Harmon Deidre
Published: September 2024

The purpose of this study was to evaluate the performance of beef cattle during the stocker phase when fed different concentrations of cotton gin byproduct (CGB). Angus steers [n = 50; initial body weight (BW) = 349 ± 66 kg) were stratified by BW and grouped in slatted floor pens (10 steers/pen). Steers were assigned randomly within pen (2 per pen) to one of five diets containing 0, 10, 20, 30, and 40% CGB (dry matter basis). Diets were balanced for protein and energy, and the steers were fed for 84 d. Steers were weighed on d -1, 0, 28, 56, 83, and 84 for the stocker phase with d -1 and 0, 83 and 84 averaged to give start and end BW. Following the growing period, steers were switched to the same finishing diet and fed for an additional 55 d prior to being transported to PA for harvest and carcass data collection. Data were analyzed using procMIXED of SASv9.4 to determine the significance of linear, quadratic, cubic, and quartic trends. During the growing phase, dry matter intake increased linearly (P = 0.0017) with 10.16, 11.23, 11.59, 11.86, and 11.96 kg/d for 0, 10, 20, 30, and 40% CGB, respectively. Average daily gain tended to increase (P = 0.0631) with a cubic trend, increasing with the first addition of CGB, declining at the intermediate levels, and then increasing again at the 40% level (1.34, 1.54, 1.36, 1.39, and 1.52 kg/d for 0, 10, 20, 30, and 40% CGB, respectively). Feed efficiency showed a similar cubic trend (P = 0.10) with 0.133, 0.138, 0.119, 0.117, and 0.128 for 0, 10, 20, 30, and 40% CGB, respectively. Within the finishing phase, average daily gain was significant (P = 0.026) as a quadratic trend with 1.54, 1.25, 1.18, 1.20, and 1.33 kg/d for 0, 10, 20, 30, and 40% CGB, respectively. Diets did not differ (P > 0.10) for dry matter intake (10.08 kg/d), feed conversion (8.31), or feed efficiency (0.130). Treatment did not influence (P > 0.10) marbling or other carcass measurements. Data suggest CGB supported good animal gains with only minor impact on feed intake and feed efficiency for stocker steers up to an inclusion rate of 40%.
PSIII-3 Evaluation of low-cost cow-side tests in developing a selective dry cow therapy program
Authors: Burner Carmen M , Callaway Todd R , Ryman Valerie E
Published: September 2024

Blanket dry cow therapy accounts for approximately one third of antibiotic use on dairies. Selective dry cow therapy (SDCT) is a management strategy that selects quarters or cows to be treated with antibiotics based on herd and/or cow-level criteria. Options for implementing SDCT include both cow-side tests (low-cost, rapid tests and higher cost culture-based SDCT) and historical data (algorithm-based SDCT), or a combination. Considerations made when exploring SDCT options include differences in diagnostic efficacy, cost, etc. The objective of this study is to evaluate the accuracy of common low-cost cow-side tests for diagnosing infection in the development of a SDCT program relative culture-based SCDT. In particular, the California Mastitis Test (CMT) and milk conductivity as measured by Mas-D-Tec were selected given their low input and per cow cost ($17 kit at < $0.10/cow and $400 device with negligible per cow cost, respectively). Late-lactation dairy cows (n = 47) at the University of Georgia Teaching Dairy were enrolled 48 h prior to dry off. On enrollment day, quarter milk samples were aseptically collected, tested utilizing CMT and milk conductivity was recorded. Milk samples were then plated on blood agar, following which, plates were evaluated for microbial growth 48 h later. Quarters were identified as bacteriologically infected or uninfected based on microbial growth. Cow-based SDCT, rather than quarter-based SDCT, was evaluated in this study. Overall, 23.40% of cows were infected at collection. Relative to culture-based selection, the sensitivity and specificity of CMT was 90.9% and 13.9% whereas the sensitivity and specificity conductivity was 81.8% and 27.8%. However, analysis indicated effects seen were not significant (P > 0.05). As a result of CMT and conductivity not yielding a significant effect, a third, yet more costly, cow-side test was evaluated. Selecting cows based on increased milk somatic cell count (SCC) is a central piece in algorithm-based SDCT. Relative to culture-based selection, SCC as a diagnostic indicator was significant (P = 0.01) with a sensitivity of 90.1% and specificity of 55.6%. The accuracy of SCC as a diagnostic tool was 63.8%. Additional data are needed to fully evaluate the applicability of CMT and conductivity as measured by the Mas-D-Tec, especially when considering the perceived economic benefits of implementing SCDT with rapid, low-cost cow-side tests. Utilization of SCC is a viable option given our findings however initial input costs (>$3,000), per cow screening costs ($3 to $12), and labor are all examples of barriers to implementation. In conclusion, the low-cost, rapid cow-side tests assessed in the current study were not effective as diagnostic tools for SDCT. Considering another cow-side test (SCC) may be necessary for producers interested in reducing antibiotic usage and costs. Dairy producers would realize a 45% decrease in dry cow therapy costs and 42% reduction in antibiotic use.
PSIII-15 Feeding patterns of yearling Angus bulls based on feed efficiency metrics
Authors: Katz Amelia R G , Huzzey Julie M , Dubowsky Jason P , McFarlane Zachary D
Published: September 2024

The study objective was to determine how feeding behavior relates to feed efficiency in yearling Angus bulls at the Cal Poly Bull test. Bulls (n = 102) were housed in four pens sorted according to initial body weight (BW; 460 ± 35, 407 ± 15, 374 ± 20, 323 ± 30; mean kg ± SD), resulting in 24 to 28 bulls/pen. Feeding behavior was monitored using an electronic feeding system (SmartFeed, C-Lock, Inc.) during an 85-d feed efficiency test. Four feeders in each pen were filled twice daily at approximately 0630 h and 1700 h. The number of visits to the feed bunk, visit duration, total feeding time, and hourly feed intake were determined from data collected from the feeding system. These data were summarized by hour in a 24-h period, across the 85-d period. Bulls were retrospectively classified into a high feed efficiency group (HIFE) and low feed efficiency group (LOFE) based on an assessment of their summed residual feed intake rank and their feed:gain ratio rank. Within each pen, 5 HIFE and 5 LOFE bulls were selected, resulting in 20 bulls/treatment used for the final analyses. Data were analyzed using the MIXED procedure in SAS 9.4. The model included the fixed effects of feed efficiency group (HIFE vs LOFE), hour (0 to 24), and the feed efficiency group × hour interaction. Bull within pen was considered a random effect and hour a repeated measure. LOFE bulls visited the bunk more frequently throughout the day during the entire testing period (P = 0.04). Differences between feed efficiency groups depended on hour and most differences were observed within 3 h of fresh feed delivery (P ≤ 0.02). A feed efficiency group × hour interaction (P < 0.001) indicated that LOFE bulls had longer feed bunk visit durations predominantly between fresh feed deliveries (P ≤ 0.048). LOFE bulls spent more time feeding throughout the entire day (P = 0.003) when compared with HIFE bulls. Feeding duration per hour was longer for LOFE bulls during the post-morning feeding period (7-h duration) and post-evening feeding period (4-h duration; P ≤ 0.045). More feed was consumed by LOFE bulls throughout the day (P < 0.001), particularly during the post-morning feeding period (P ≤ 0.05). Overall, bulls exhibiting decreased feed efficiency had different feeding behavior patterns in all behavioral categories than their more feed efficient counterparts, especially around feed delivery. Thus, more active bulls at the feed bunk were less feed efficient, and this behavioral pattern may be an important consideration in bull selection.
PSIII-13 Uncovering the genetic basis of cleft palate in Boer goats
Authors: Hoffmann Kenzy , Beever Jonathan E , Rowan Troy N
Published: September 2024

Cleft palate is a genetic deformity that can occur in several species, it is the result of the palate of the mouth not fully forming during gestation. This leaves an opening in the mouth that could extend to the nasal cavity, potentially causing the animal to be unable to eat or drink properly. This typically leads to the breeder euthanizing the animal shortly after birth. The objective of this study was to determine the genetic cause of cleft palate in Boer goats and to develop a diagnostic tool that allows producers to select against it. Blood samples (n = 15) were collected from three Boer goat herds. The samples represented six trios and one quad that included sire, dam, and affected kid(s). All affected kids were sired by the same male. Genomic DNA was extracted and used to generate libraries for whole genome sequencing. An average of 179.7 million reads were generated across all samples (range from 151.2 million to 224.4 million reads) resulting in approximately 10X genome coverage per sample. After sequencing, quality filtering was performed using a nextflow pipeline modeled after the germline short variant discovery best practices workflow from the Genome Analysis Toolkit (GATK) software. After filtering, reads were mapped to the Saanen_v1 reference genome. The pipeline called 18,867,792 variants across the 15 samples. Variants were processed using Ensembl Variant Effect Predictor (VEP) to identify potentially high-impact mutations that may be causal. Additional analyses will be used to refine this list of candidate variants for this condition.
PSV-18 Relationships between serum insulin-like growth factor 1 and cortisol in growing steers to beef production and palatability
Authors: Wesolowski Lauren T , Semanchik Pier L , Simons Jessica L , Carson Chloey P , DiSilvestro Adrianna N , Earnhardt-San Audrey L , Riley David R , Perry George A , Long Charles R , Machado Tanner J , Randel Ronald D , Welsh Thomas H , White-Springer Sarah H
Published: September 2024

Beef cattle breed and temperament are known to impact beef production; however, the physiological pathways linking stress and growth to palatability are not well understood. To test the hypothesis that live animal circulatory cortisol and insulin-like growth factor 1 (IGF1) would be related to temperament, production efficiency, and palatability, Brahman and Angus steers were classified as calm (n = 13 Angus; n = 12 Brahman), intermediate (n = 11 Angus; n = 10 Brahman), or temperamental (n = 12 Angus; n = 12 Brahman) based on their pen score and exit velocity at weaning. Serum samples collected at 10, 13, and 18 mo of age were evaluated for cortisol and IGF1 concentrations. Steers were maintained on grass pasture until they were moved to a feedlot after the 13-mo collection and provided a growing ration. Following the 18-mo collection, steers were sent to a commercial abattoir. Data were analyzed using linear models in SASv9.4 with breed, age, temperament, and all interactions as fixed effects and age as a repeated effect with animal(breed) as the subject. Relationships between variables were assessed with Pearson correlation coefficients. Calm Angus had greater IGF1 than temperamental Angus (P = 0.02) while intermediate Brahman had greater IGF1 than calm or temperamental Brahman (P ≤ 0.02). Temperamental Brahman had greater cortisol concentrations than calm and intermediate Brahman and temperamental Angus (P ≤ 0.01). In Angus, IGF1 concentrations decreased from 10 to 13 mo and from 13 to 18 mo (P ≤ 0.0006). In contrast, Brahman IGF1 concentrations increased with age to be greater at 13 and 18 mo than 10 mo (P ≤ 0.0001). Angus also had greater serum IGF1 than Brahman at 10 mo, but Brahman had greater IGF1 than Angus at 13 and 18 mo (P ≤ 0.0007). In 10 mo Brahman, IGF1 was positively correlated with animal body weight (BW) and average daily gain (P ≤ 0.005). IGF1 in 10 and 13 mo Brahman was also positively correlated with marbling (P ≤ 0.03). IGF1 in 13 mo Angus was positively correlated with Warner-Bratzler shear force (P = 0.02). Cortisol concentrations in Angus were greater at 10 and 13 mo than at 18 mo (P ≤ 0.004) leading to 10 mo Angus having greater cortisol concentrations than Brahman of the same age (P = 0.05). In Angus, at 10, 13, and 18 mo, cortisol was positively correlated with animal BW and hot carcass weight (P ≤ 0.05). At 10 and 13 mo, cortisol was positively correlated with ribeye area in Angus (P ≤ 0.005). These data suggest that serum IGF1 in Brahman is related to growth and lipid metabolism, and tenderness in Angus. However, cortisol concentrations have a more prevalent relationship with Angus growth and subsequently beef production. This project was supported by USDA NIFA Award #2021-67015-33392.
PSV-11 Significance of specialty protein ingredients in feeding programs for broiler chickens on nitrogen utilization and excretion- A meta-analysis
Authors: Njeri Felix M , Ellis Jennifer L , Kiarie Elijah
Published: September 2024

The utility of specialty protein ingredients (SPI) in feeding programs for broiler chickens is premised on poor utilization of conventional vegetable proteins (CVP). The SPI includes ingredients of animal origin such as processed animal proteins (PAP), insect proteins (IP) and further processed conventional vegetable proteins (PCVP) characterized with greater concentration of crude protein/amino acids, and low anti-nutritional factors. The objective of this study was to apply meta-analysis approach of published studies that incorporated SPI to provide insights into their effectiveness on nitrogen utilization and excretion in broiler chickens. The data were retrieved from Web of Science, PubMed, ScienceDirect, hand searching and cross-referencing, and resulted in 44 publications meeting inclusion criteria such as being a broiler study and treatments diets being isocaloric and isonitrogenous Model development was performed in PROC GLIMMIX of SAS and treated the study as a random effect. The SPI protein source (PAP, IP, and PCVP), bird age (starter 0 to 14 d, grower 14 to 24 d and finisher 25 to 42 d), nitrogen intake and level were the main X variables of interest, while outcome (Y) variables explored included nitrogen excretion, nitrogen retention, nitrogen efficiency, average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR). To address heterogeneity in sample size and errors between treatment means from different studies, the WEIGHT statement in PROC GLIMIXX was employed to weight variables using the inverse of their squared variance. The inclusion or rejection of models developed was based on the evaluation of root mean square prediction error and concordance correlation coefficient. Comparatively, the slopes of PAP, IP and PCVP (soybean meal) linearly reduced and quadratically (P < 0.05) increased ADG during the starter phase against their respective controls. The extent ADG was greatest with intake of PCVP followed by PAP. During the grower phase, ADG was highest for PAP, followed by IP with PCVP being the least (P < 0.05). However, PCVP had the greatest ADG during the finisher phase (P < 0.05). On nitrogen excretion, provision of PAP during the stater phase increased the nitrogen excretion while it reduced the excretion during the grower and finisher phase (P < 0.05) relative to control. The intake of IP up to 10% inclusion reduced nitrogen excretion only during the starter and grower phase (P < 0.05) when compared with respective controls. The intake of PCVP reduced nitrogen excretion in all growth stages compared with respective controls (P < 0.05). In conclusion specialty proteins (PAP and PCVP) and insect protein at an inclusion level of < 10%, were effective ways of reducing nitrogen excretion while improving growth performance. Combining these strategies may have a synergistic effect.
PSV-3 Lifetime plasma concentration of select trace minerals in broiler chickens hatched from broiler breeders fed hydroxychloride or organic sources of zinc, copper, and manganese
Authors: Bakhshalinejad Reza , Torrey Stephanie , Kiarie Elijah
Published: September 2024

The objective was to investigate the effects of feeding broiler breeders (BB) hydroxychloride (HC) or organic (OR) sources of zinc (Zn), copper (Cu), and manganese (Mn) from 42 to 63 wk of age (woa) on plasma concentration of trace minerals (TM) in offspring at hatch through to 42 d of life (Table 1 to 4). A total of 408 ♀ Ross 708 and 48 ♂ Yield Plus cockerels were placed in pens (17 ♀ and 2 ♂) and allocated to one of two diets: 1) HO, a blend of 80% HC and 20% OR sources, and 2) OR, 100% OR sources. In total, 2,160 eggs (90 eggs from each pen replicate) were collected and labelled by BB pen at 46, 52 and 62 woa and incubated. Upon hatching, chicks were sexed, weighed, and placed in 24 pens (40 birds/pen) within BB diet identification. For offspring phase, one-half of chicks from BB fed HO or InO were fed HC and the other half were fed inorganic (InO) sources of Zn, Cu and Mn, effectively creating 4 treatments for offspring phase (n = 6; 3 pens per sex). There were no BB diets effects (P > 0.05) on plasma concentration in hatchlings (Table 5, 6). However, BB age effect was such that plasma of hatchlings of 54- and 62-wk-old BB exhibited increased concentrations of Zn, Cu, and Mn compared with those from 46-wk-old parents (P < 0.0001; Table 6-7). Additionally, female hatchings displayed greater Cu concentrations in plasma compared with males (P = 0.024). Broiler chickens fed HC exhibited greater plasma Zn, Cu, and iron on d 21 compared with the other groups (P < 0.05) while 42-d chickens fed HC diet exhibited increased concentrations of Mn and iron compared with the other groups (P < 0.05). Forty-two-d old broiler chickens from 62-wk-old breeders exhibited greater TM concentrations compared with those from younger parents (P < 0.0001). The findings provide valuable insights for enhancing TM supplementation in BB diets to enhance the plasma concentrations of Zn, Cu, and Mn in offspring. Notably, hatchlings fed with HC as a source of Zn, Cu, and Mn exhibited increased concentrations of these minerals through 42 d.
PSV-19 Uncovering breed-origin allele effects and their role in thermotolerance through genome-wide association study in Brangus cattle
Authors: Zayas Gabriel A , Rojas Camila Santos , Hernandez Aakilah , Rodriguez Eduardo E , Beard Ashley , Rafiq Fahad , Davila Kaitlyn Sarlo , Mateescu Raluca
Published: September 2024

In subtropical and tropical environments, beef cattle production faces significant challenges due to heat stress, affecting animal welfare and productivity. To mitigate these effects, producers have turned to crossbreeding and the development of composite breeds like Brangus, which combine the desirable carcass and meat quality traits of European taurine cattle with the thermotolerance of Indicine breeds. However, the genetic underpinnings of thermotolerance in these composite populations are not well understood, owing to the complex nature of measuring related traits and the genetic intricacies arising from crosses of distinct populations. This study aims to identify key quantitative trait loci (QTL) related to thermotolerance, employing an approach that integrates genetic markers alongside the marker’s breed of origin of alleles (BOA) in Brangus heifers. Data were collected on histological sweat gland area (SWA), hair length (HL), and thermal stress slope as a measure of the increase in body temperature from a low to a high temperature-humidity index (TSS), from 2,233 Brangus heifers genotyped with the 250K functional chip. BOA was determined using LAMP-LD software, using Angus and Brahman cattle from the University of Florida’s multibreed Angus-Brahman project as a reference population. We conducted a genome-wide association study (GWAS) incorporating BOA-specific effects, revealing several genes with BOA-specific effects. Notably, the CGGBP1 gene exhibited a significant effect on TSS only when alleles originated from Brahman. Conversely, the PLK1 gene was significant for TSS when alleles originated from Angus. Both CGGBP1 and PLK1 interact with heat shock proteins during heat stress, these findings reveal different genetic mechanisms for controlling internal body temperature. For HL, a significant Brahman-specific effect was found near the PRLR gene, which is known as the gene controlling the SLICK hair phenotype in Criollo cattle. For SWA, an Angus-specific significant association was found with the PDE4D gene. PDE4D interacts with the cAMP pathway which regulates sweat gland growth and sweat production. These findings underline the genetic complexity of thermotolerance in composite cattle and the crucial role of BOA in identifying key QTL. The study offers novel insights into the genetic mechanisms of thermotolerance, providing a foundation for breeding strategies aimed at improving heat resilience in cattle in subtropical and tropical environments.
PSV-1 Trio-binning Assemblies of the Duroc and Landrace swine breeds
Authors: Ackerson Leland K , Kuhn Kristen , Gondro Cedric , Jiang Jicai , Maltecca Christian , Rohrer Gary A , Rosen Benjamin D , Smith Timothy , Tuggle Christopher K , Huang Wen
Published: September 2024

The current swine reference genome, based on a single Duroc individual, has contributed to many significant advances but also carries limitations in many applications. Reference alleles receive substantial bias from alignment-based approaches. Additionally, structural DNA variants are difficult to identify and represent relative to the linear reference genome. As a result, DNA variants more likely to affect complex quantitative traits are understudied and warrant further investigation. In this study, a trio-binning approach was utilized to produce haplotype-resolved assemblies of a Duroc x Landrace hybrid. The Duroc sire and Landrace dam were sequenced via short-read technology (Illumina), and the hybrid offspring was sequenced via long-read technology (PacBio HiFi). A total of 117 Gb HiFi data was produced, equivalent to approximately 47X coverage of the swine genome. Two highly contiguous and high-quality assemblies were produced using hifiasm. The assembled maternal (Landrace) and paternal (Duroc) genomes had a contig N50 of 76.7 Mb and 55.0 Mb, respectively, both of which surpass that of the current reference genome Sscrofa11.1 (48.2 Mb). Furthermore, the maternal and paternal genomes contained 113.6 Mb and 116.0 Mb of novel sequences relative to the reference, respectively. The Benchmarking Universal Single-Copy Orthologue (BUSCO) scores were approximately 96%, indicating high completeness. The computed assembly QVs were found to be >Q40. Compared with short-read technology, whole genome mapping identified substantially more large SVs (> 50bp). These haplotype-resolved assemblies and additional existing assemblies will serve as the basis for the production of a swine pangenome.
PSV-15 Evaluating the relationship between subcutaneous backfat thickness and sperm morphology in young beef bulls
Authors: Smith Molly , Aguilar Jorge Octavio Solano , Nyhuis Grace , Henry Francine M , Stewart Lawton , Duggin Jason , Fontes Pedro
Published: September 2024

Literature indicates that high-energy diets can lead to reductions in both sperm motility and morphology in bulls. This study aimed to investigate the relationship between individual variation in subcutaneous backfat thickness (SCBF) and sperm morphology in young beef bulls exposed to the same diet. We hypothesized that bulls with excessive subcutaneous fat thickness have increased sperm morphology defects compared with bulls with adequate subcutaneous backfat thickness. Historical data collected from yearling Bos taurus beef bulls (n = 557) enrolled in a bull development program were used in an observational retrospective cohort study to test this hypothesis. Over the course of 5 yr, bulls in two locations were developed according to industry standard practices, and performance was evaluated over 84 d with a 21-d adaptation period. At the end of the performance evaluation period, a carcass ultrasound was performed to evaluate ribeye area, SCBF, and intramuscular fat. Furthermore, breeding soundness examinations (BSE) were performed according to the Society of Theriogenology guidelines within 40 d after carcass ultrasonography. Bulls that failed the BSE for reasons unrelated to semen quality were excluded from this study. Within each year, bulls were ranked based on SCBF and classified as top 10% (TOP; n = 55), middle 80% (MID; n = 446), and bottom 10% (BTM;n = 56) for SCBF. Initial body weight (BW) was greater (P < 0.01) in TOP bulls compared with MID and BTM (Table 1). Off-test BW was also greater in TOP compared with MID and BTM bulls (P < 0.01). In contrast, average daily gain and scrotal circumference did not differ between experimental groups (P = 0.35 and P = 0.65, respectively). TOP bulls had greater (P < 0.01) SCBF compared with MID and BTM, and MID bulls had greater (P < 0.01) SCBF compared with BTM bulls. Similar results were observed for intramuscular fat (P < 0.01) and ribeye area (P < 0.01). Percentage of normal sperm cells was greater in both BTM and MID bulls compared with TOP bulls (P < 0.01). Additionally, percentage of primary abnormalities tended (P = 0.07) to be greater in TOP bulls compared with BTM and MID. There were no differences in the percentage of secondary abnormalities between experimental groups (P = 0.45). There was a tendency (P = 0.07) for a greater percentage of TOP bulls to fail the BSE compared with MID and BTM bulls. Moreover, there was a positive linear relationship (P = 0.01) between SCBF and the probability of failing the BSE. In summary, elevated SCBF in bulls exposed to the same diet was associated with an increase in sperm morphological abnormalities and tended to increase the percentage of bulls failing the BSE.
PSVI-17 Effects of maternal nutrition during gestation on second parity F2 offspring growth and organ weights
Authors: Summers Cheyenne S , Reiter Amanda S , Tillquist Nicole M , Barnello Nicholas M , Voggu Santhi Priya , Carter Rachel E , Kawaida Mia Y , Govoni Kristen E , Zinn Steven A , Reed Sarah A
Published: September 2024

Maternal diet influences offspring growth, but the impact of granddam diet on subsequent generations is less explored. We hypothesized that granddam diet would influence second parity F2 offspring growth. The objective of this study was to determine the influence of granddam diet on second parity F2 offspring growth, morphometric measurements, and organ weights. To determine the impact of poor maternal nutrition of F0 dams on second parity offspring of F1 ewes, multiparous Dorset ewes (F0, n = 46) were fed 100% (control), 60% (restricted), or 140% (over) of NRC requirements from d 30 of gestation until parturition. The F1 ewes (n = 37) were bred at 16 to 19 mo of age to one of two related Dorset rams to generate the first parity F2 generation. The following breeding season, F1 ewes (n = 30) were bred to the same rams to generate the second parity F2 generation offspring (n = 58; F2-2), which were identified as CON F2-2 (n = 6 ewes, 12 rams), RES F2-2 (n = 6 ewes, 12 rams), or OVER F2-2 (n = 9 ewes, 13 rams) corresponding to the diets of the F0 granddams. F2-2 offspring body weights (BW) were recorded weekly from birth (d 0) to d 28, every 14 d until d 126, and every 28 d until d 266 of age. Hip height (HH), crown rump length (CRL), heart girth (HG), and body condition score (BCS) were measured at d 0 and d 120 of age. Rams were necropsied at d 284 ± 0.23. Data were analyzed with R Studio with P ≤ 0.05 considered significant and 0.05 < P ≤ 0.10 considered a tendency. Granddam diet and offspring sex were included in the model with animal ID as a random effect where appropriate. On d 210 and d 238, CON F2-2 tended to weigh 6.8% and 6.3% less, respectively, than OVER F2-2 (P = 0.07) but were not different than RES F2-2 at d 210 (P = 0.55) or d 238 (P = 0.15). We did not detect an effect of granddam diet on HH (P = 0.28), CRL (P = 0.31), or HG (P = 0.62) at birth. At d 120, ewes had 3.1% shorter CRL (P = 0.07) and weighed 9.4% less (P = 0.003) than rams. Immediately before necropsy, CON F2-2 rams tended to have 5.9% less BCS compared with RES F2-2 rams (P = 0.07) and 5.6% less BCS than OVER F2-2 rams (P = 0.10). At necropsy, granddam diet did not influence organ weight. Overfed and restricted granddam diet may increase BW and BCS of second parity, second generation offspring, which provides evidence that maternal diet has multigenerational effects on offspring.
PSVI-5 Bacteriophage biocontrol of avian pathogenic Escherichia coli in laying hens does not produce collateral effects on the cecal microbiota
Authors: Gohar Mawra , Hyun Jenny , Smith Riley , Waldner Matthew , Mehina Nabiha , Alexander Trevor , Nyachoti C Martin , Fairbrother John , Careem Faizal Abdul , Niu Dongyan
Published: September 2024

Bacteriophages have shown promise as an alternative to antibiotics for managing or preventing avian pathogenic Escherichia coli (APEC) in the egg industry. In a previous study, a phage cocktail comprising 3 virulent phages was shown to prevent APEC infections in laying hens. The aim of this study was to investigate whether orally and intramuscularly administered phages affect the intestinal barrier function of chickens, with a focus on cecal microbiome. In a 4-d trial, a total of 35 laying hens were randomly assigned to one of four treatment groups: 1) Medium control group (bacterial broth + phage buffer), 2) APEC only control (APEC + buffer); 3) IM group (Phage +APEC), or 4) DW group (phage in drinking water (4 d prior to APEC + APEC). Cecum samples were subjected to 16S rRNA gene sequencing targeting the V4 region to assess the effects of phages on cecal bacterial diversity. A 1-way ANOVA was used to evaluate alpha diversity with respect to treatment and time. Microbial community structure was analyzed using β-dispersion and permutational multivariate analysis of variance (PERMANOVA) to determine the effect of each treatment. Significant (P < 0.05) differentially abundant genera were identified with DESeq2 by fitting a negative binomial model to each treatment vs treatment comparison (“~Treatment”). Across the treatment and control groups, 13 phyla were identified. Firmicutes (53.81%), Bacteroidota (23.83%), Actinobacteriota (1.84%), and Proteobacteria (1.02%) were the most abundant phyla among the amplicon sequence variants (ASVs), with 18.39% being unclassified. Neither richness (P = 0.448) nor Shannon diversity (P = 0.687) exhibited significance in α- diversity metric between treatment and control groups. β-dispersion analysis showed no significant difference (P = 0.239) between treatment and control groups, indicating similar bacterial variability among groups. Moreover, the β-diversity representing microbiota structure was not affected by any phage treatment (P = 0.083). In each treatment group, 76 unique genera were identified, with Megamonas (15.80 %), Lactobacillus (8.76%), Faecalibacterium (7.70 %), Megasphaera (1.58%), Alloprevotella (1.54%), [Ruminococcus] torques group (1.29%), Prevotellaceae UCG-001 (1.14%), Bifidobacterium (1.04%), and Olsenella (0.48%) being the most abundant. Notably, Lactobacillus was more abundant (~ 10 to 20%) in medium control group compared with phage treated and APEC only treatment groups. Furthermore, gene expression profiles of various genera (pairwise) were analyzed using log2 fold change (log2FC), revealing differences (P < 0.05) between control and treatment groups for a total of 58 genera. It was concluded that bacteriophage selectively killed APEC population without comprising the population and structure of cecal microbiome in laying hens.
PSVI-12 Clodronate does not impact bone optical density or lameness in juvenile, exercised Quarter Horses
Authors: Paris Brittany L , Leatherwood Jessica L , Welsh Thomas H , Glass Kati G , Arnold Carolyn E , Conrad Matthew B , George James M , Martinez Rafael E , Colbath Aimee C , Nielsen Brian D , Bradbery Amanda N
Published: September 2024

The non-nitrogenous bisphosphonate clodronate disodium (CD) inhibits bone resorption and is approved for horses ≥ 4 yr of age. Extra-label use in juvenile exercising horses is a concern due to potential interference with normal bone growth and development. The objective was to determine the effects of single and repeated doses of CD on bone optical density (radiographic bone aluminum equivalence; RBAE) and lameness score (LS) in juvenile, exercising horses. Quarter Horses [n = 32 (16 geldings, 16 fillies); 500 ± 13 d of age; body weight (BW) = 336 ± 26 kg]) were used to test the hypothesis that horses receiving CD would have greater RBAE and reduced LS, and additional doses of CD would accentuate these effects. In a 168-d trial, horses were housed in individual stalls, and fed 1% BW/d concentrate and ad libitum Coastal bermudagrass hay. Horses were exercised 5 d/wk following a phase-based progressive workload using a free stall exerciser; Phase I (d 0 to 84) mimicked sales preparation whereas Phase II (d 85 to 168) simulated early training. Horses were stratified by age, BW, sex, and initial RBAE into control (CON; n = 8), single dose CD (1X; d 84; n = 8), 2-doses CD (2X; d 0 and d 84; n = 8), and four-doses CD (4X; d 0, d 42, d 84, d 126; n = 8). On injection d (0, 42, 84, and 126), horses were administered either 1.8 mg/kg BW CD (OSPHOS) or isovolumetric saline. On d 0, 84, and 168, dorsal-palmar and lateral-medial radiographs of the left third metacarpus and metatarsus were captured. An aluminum step wedge was included in each image and raw images were analyzed (Quantity One Basic, BioRad) to determine total bone RBAE at 1 cm distal to the nutrient foramen. On d 0 and d 168, horses were evaluated by a veterinarian unaware of treatment group and assigned a LS according to the American Association of Equine Practitioners Lameness Scale. The RBAE and LS data were analyzed via PROC MIXED and PROC GENMOD, respectively, in SAS. For each view, RBAE increased from d 0 to d 84 and remained increased to d 168 (P ≤ 0.02), regardless of treatment, likely due to progressing exercise protocol. On d 0, 29 horses were LS 0, 1 horse was LS 1, and 2 horses were LS 2; LS did not differ among treatment groups (P = 0.61). On d 168, 5 horses were LS 0, 13 horses were LS 2, 11 horses were LS 3, and 1 horse was LS 4; LS did not differ among treatments (P = 0.16). Based on these results, the hypothesis that single or repeated CD administration would increase RBAE and decrease lameness in juvenile, exercised Quarter Horses was rejected. Funding: AFRI#2021-67015-34079
PSVI-18 Association between residual feed intake and reproductive-related traits in young bulls
Authors: Venturini Mauro , de Losano Joao Agostini , Heredia Daniella C , Duarte Maria C Lopez , Mcgraw Maura , Muhammad Sohail , Guertin Jillian , Dilorenzo Nicolas , Daigneault Bradford W , Gonella-Diaza Angela M
Published: September 2024

Enhancement of feed efficiency (FE) along with reproductive performance is critical to maximize profitability of beef production systems. Residual feed intake (RFI) is a measure of FE, assessing differences between expected and actual feed intake. Published data suggest a negative impact of RFI on reproductive performance. The objective of this experiment was to establish the relationship between RFI and reproductive parameters related with puberty in young bulls. Growing, Brangus bulls (n = 58; 10 to 12 mo of age) were tested for FE over 56 d and ranked as low RFI (LRFI) and high RFI (HRFI). Scrotal circumference (SC) was measured at the greatest diameter of the testicles by the same operator using a scrotal measuring tape, and semen samples were collected by electroejaculation at the beginning and at the end of the test. Fresh semen was visually evaluated (VE) for visual motility (VM), morphology [major defects (MAD)], minor defects (MID), total defects (TD)], plasma membrane integrity (PMI) via Eosin-nigrosin stain and sperm concentration (Con). Sperm kinematics were objectively determined simultaneously via computer-assisted sperm analysis (CASA-IVOS II System, Hamilton Thorne, Beverly, MA) within 6 h of collection in a medium designed specifically for holding sperm. Statistical analysis included repeated measures to assess interactions between Group (LRFI, HRFI) and Time (0 and 56 d of RFI measurement). Results are presented as mean ± SEM in Table 1. The main effect of Group did not affect CASA derived traits, while MAD and TD were affected among VE traits. A Time effect was observed in the amplitude of lateral head displacement (ALH), beat cross frequency (BCF), curvilinear velocity (VCL) and linearity (LIN). A tendency was indicated for total motility (TM), and average path velocity (VAP) among CASA derived traits, while all VE traits were affected by Time except for visual motility (VM). Finally, an interaction effect (Group x Time) was observed in LIN and plasma membrane integrity (PMI). In conclusion, age at puberty as determined by VM, Con, and SC (Group: P = 0.12, Day: P < 0.001, Group x Day: P = 0.79) was not associated with RFI. Overall, fertility-related measurements were not influenced by RFI, with time emerging as the primary influencing factor across evaluated parameters. Evaluation of reproductive parameters following d 56 FE testing may be a useful determinant for identifying differences in seminal characteristics of young bulls.
PSVI-2 Multigenerational effects of maternal rate of body weight gain on fetal liver miRNA expression
Authors: Anas Muhammad , Ward Alison K , McCarthy Kacie L , Borowicz Pawel P P , Reynolds Lawrence P P , Caton Joel S S , Dahlen Carl R , Da Diniz Wellison Jarles Silva
Published: September 2024

Maternal rate of gain is critical to heifer development, pregnancy outcomes, and cow longevity. Multigenerational epigenetic effects in offspring resulting from differing levels of maternal body weight (BW) gain in heifers have not been explored previously in beef cattle. The objective of this study was to evaluate the effects of early gestational BW gain in beef heifers on epigenetic mechanisms regulating gene expression in the fetal liver of the F1 generation and to determine their persistence into the F2 generation. Therefore, we hypothesized that the heifer rate of BW gain during early pregnancy would alter the hepatic micro-RNA (miRNA) expression profile of the F1 generation and that these effects would persist into the F2 offspring. Angus cross-bred heifers (n = 132; ~13 mo of age) bred through artificial insemination were assigned to treatments targeting different rates of BW gain (LG; low BW gain targeting 0.28 kg/d, n = 66; or MG; moderate BW gain targeting 0.79 kg/d, n = 66). Fifteen F0 pregnant heifers (LG = 7, MG = 8) were slaughtered on d 83 of gestation, and F1 fetal liver samples were collected. The remaining pregnant heifers (LG, n = 23; MG, n = 25) were maintained on pasture and managed as one group through calving and weaning, with no dietary treatments. The F1 heifers were then bred and slaughtered to collect the fetal liver tissues of the F2 generation from 16 pregnant heifers (LG = 8, MG = 8) on d 83 of pregnancy. The fetal hepatic miRNA profiles of F1 and F2 generations were determined using miRNA-Seq. The data were analyzed using the mirDeep2 pipeline, and differentially expressed miRNAs were identified (FDR < 0.05). Bta-miR-206 was the only differentially expressed miRNA in both the F1 and F2 generations for the MG vs. LG comparison. Based on gene target predictions, 809 genes are targeted by this miRNA. Functionally over-represented pathways (FDR < 0.05) of targeted genes included key energy metabolic pathways like mTOR, Wnt, MAPK, and PI3K-Akt signaling pathways, along with thyroid hormone signaling and longevity-regulating pathways. The results indicated that the effects of the F0 maternal rate of BW gain persisted into the F1 and F2 generations, and the maternal rate of BW gain during early pregnancy altered the hepatic miRNA expression profile to potentially regulate energy metabolism in beef heifers.