bluuebunny/crossref_metadata_2025 huggingface dataset:
PSX-3 Transcriptional response to an alternative diet on liver, muscle, and rumen of beef cattle
Authors: Fernandes Anna Carolina , Reverter Antonio , Keogh Kate , Alexandre Pâmela Almeida , Afonso Juliana , Palhares Júlio César Pascale , Cardoso Tainã Figueiredo , Moraes Malheiros Jéssica M , Bruscadin Jennifer Jéssica , de Oliveira Priscila Silva Neubern , Mourão Gerson Barreto , de Regitano Luciana Correia Almeida , Coutinho Luiz Lehmann
Published: September 2024

Feed cost represents a major economic determinant within cattle production, amounting to an estimated 75% of the total variable costs. Consequently, comprehensive approaches such as optimizing feed utilization through alternative feed sources, alongside the selection of feed-efficient animals, are of great significance. Here, we investigate the effect of two diets, traditional corn-grain fed and alternative by-product based, on 14 phenotypes related to feed, methane emission and production efficiency and on multi-tissue transcriptomics data from liver, muscle, and rumen wall, derived from Nellore bulls (n = 52), 26 on each diet. To this end, diets were contrasted at the level of phenotype, gene expression, and gene-phenotype network connectivity. As regards the phenotypic level, at a P-value < 0.05, significant differences were found in favor of the alternative diet for average daily weight gain at finishing, dry matter intake at finishing, methane emission, carcass yield and subcutaneous fat thickness at the rib-eye muscle area. In terms of the transcriptional level of the 14,776 genes expressed across the examined tissues, we found 487, 484, and 499 genes differentially expressed due to diet in liver, muscle, and rumen, respectively (P-value < 0.01). To explore differentially connected phenotypes across both diet-based networks, we focused on the phenotypes with the largest change in average number of connections within diets and tissues, namely methane emission and carcass yield, highlighting, in particular, gene expression changes involving SREBF2, and revealing the largest differential connectivity in rumen and muscle, respectively. Similarly, from examination of differentially connected genes across diets, the top-ranked most differentially connected regulators within each tissue were MEOX1, PTTG1, and BASP1 in liver, muscle, and rumen, respectively. Changes in gene co-expression patterns suggest activation or suppression of specific biological processes and pathways in response to dietary interventions, consequently impacting the phenotype. The identification of genes that respond differently to diets and their associated phenotypic effects serves as a crucial steppingstone for further investigations, aiming to build upon our discoveries. Ultimately, such advancements hold the promise of improving animal welfare, productivity, and sustainability in livestock farming.
PSX-5 Repeatability of overreach, term and acuteness in Peruvian Paso horse
Authors: Vilela Jorge L , Quintana Paola D , Velarde Maria L , Chacon Jose Dextre
Published: September 2024

The Peruvian Paso Horse is considered one of the best saddle horses worldwide due to the gait that makes this horse perform one of the smoothest walks. The overreach, term, and acuteness are the most characteristic movements in the gait, making them the most desirable attributes in its breeding and reproduction. Repeatability of overreach, term, and acuteness in Peruvian Paso horses (PPH) have not been determined to date. It is important to estimate this parameter for application in PPH breeding, therefore, the aim of this study was to estimate the repeatability of overreach, term, and acuteness of PPHs. The study included records of 137 stallions and mares. All measurements were recorded in MP4 video format with a resolution of 1920 x 1080 megapixels and at 60 frames per second. All traits were measured three times (once per stride), and each trait was analyzed. KINOVEA software version 0.9.5 was used to analyze the measurements. A multivariate repeated measures animal model with sex effect was used to estimate the variance components for each trait using WOMBAT software. Repeatability was high in all traits (> 0.78; Table 1). The low standard error values close to 0.02 indicate high precision in all traits (0.904, 0.855, and 0.903 for overreach, term, and acuteness, respectively), being defined as the variance of the mean of “n” measurements as a percentage of the variance of one measurement, indicating that this parameter has little effect on the temporal environment of the three traits. These results demonstrate that previous training can influence the regularity of the gait, in agreement with the present study, in which only adult animals that have already had previous training were evaluated. Furthermore, our results corroborate that traits with high repeatability require few measurements (3 in this study) to obtain greater precision, and an increase in the number of measurements may be irrelevant for parameter estimation. In a breeding plan, this high precision may be due to an increase in the additive genetic variance, indicating that two or more measurements have greater heritability than a single measurement, allowing a better breeding value estimate to be obtained. Considering the high repeatability values found, this parameter can be used as an indicator of how effective the selection process can be, considering its relationship with heritability, as repeatability values are higher than heritability, due to the inclusion of permanent environmental variance (within-individual variance) in its estimation. High values also indicate that individuals tend to have consistent performance, and therefore, obtaining several measures for evaluation may be impractical. It can be concluded that overreach, term, and acuteness have high repeatability values, which allows these traits to respond better in a selection process and performance evaluation for subsequent competitions.
PSX-4 Exploring the impact of age and body condition score on the genetic analysis of mature cow weight in American Angus cattle
Authors: Ojo Ayooluwa O , Campos Gabriel S , Mulim Henrique A , Garcia Andre , Schinckel Allan P , Miller Stephen , Retallick-Riley Kelli J , Oliveira Hinayah R
Published: September 2024

Selecting sires with optimal genetic merit for mature weight (MWT) is crucial for profitability of beef producers, ensuring cost-effective production and increased economic returns per animal. The main objective of this study was to determine how different statistical approaches [e.g., including the fixed effects (FE) of age and body condition score (BCS) in the statistical model and/or pre-adjusting the weights for these effects] affect variance components estimation and genetic parameters for MWT, and their impact in the posterior selection decisions. The dataset provided by the American Angus Association (AAA) comprised 80,296 MWT records from 37,934 cows aged 2 to 15 yr. Contemporary groups (CG) were defined by concatenating herd, year, and season of measurement. Model 1 analyzed unadjusted MWT with CG and BCS as categorical FE and age as a covariable (quadratic). Model 2 was model 1 without BCS, model 3 was model 1 without age, and model 4 considered CG as the only FE. In model 5, MWT was pre-adjusted for 6 yr of age and BCS of 6, and CG was the only FE included in the statistical model. Additive genetic and permanent environment (pe) random effects were included in all statistical models except model 5, which did not include pe (only one adjusted record per animal). Variance components were calculated using REML implemented in the BLUPf90+ family of programs. Sires with at least 10 offspring (n = 1,483) were ranked according to their breeding values (EBVs) predicted for MWT, and all and the top 10% sires were used to estimate the rank correlation across models. The heritability (± SE) estimated for MWT was 0.43 (± 0.011), 0.42 (± 0.011), 0.70 (± 0.008), 0.72 (± 0.082), and 0.37 (± 0.013) for models 1, 2, 3, 4, and 5, respectively. Repeatability values were 0.64, 0.67, 0.72, and 0.76 for models 1, 2, 3, and 4, respectively. The EBV ranks were highly correlated between models 1 and 2 (Top 10%: 0.96; All: 0.99), and models 3 and 4 (Top 10%: 0.99; All: 0.99). Inflated heritabilities in models 3 and 4 suggest that the effect of age is confounded with the additive genetic effect, which will not translate to greater genetic progress. Therefore, disregarding age in the genetic evaluation of MWT is not recommended. Similarities between models 1 and 2 suggest that BCS has a relatively small impact on MWT, probably related to the relatively low genetic correlation between these traits. Models 1 and 5 cannot be directly compared, as they use slightly different response variables (body weight vs. pre-adjusted weight) and may lead to slightly different selection decisions (correlation between Top 10%: 0.85; All: 0.95). Further investigations in this field are warranted.
PSX-10 Genome-wide association studies for clinical mastitis in dairy cattle
Authors: Chen Zikai K , Seto Desiree , Campos Fernando , Huzzey Julie M , Peterson Dan , Sprayberry Kim , Sargolzaei Mehdi , Anderson Paul , Altermatt Joy , Golden Bruce , Pokharel Siroj , Abo-Ismail Mohammed
Published: September 2024

Mastitis, the inflammation of the mammary gland caused by both gram-positive and gram-negative bacteria, causes the global dairy industry over $20 billion annually in losses due to changes in milk yield and quality. The goal of this study was to identify genetic variants, genes, and biological pathways that are associated with mastitis. We performed genome-wide association studies (GWAS) on 1,858 cows from two lactations with both medium (n = 87,493) and high density (n = 624,300) single nucleotide polymorphisms (SNP) using a single SNP mixed linear model implemented in GCTA software. A total of 288 SNPs across all evaluated models passed the 5% genome-wise false discovery rate threshold across all autosomes with emphasis on chromosomes 3, 14, 16, 12, 6, and 2. These SNPs were mapped to their corresponding genes using the bovine genome. Gene enrichment analysis was then performed to identify significant biological pathways associated with mastitis. The current study identified potential genes that are involved in the MAPK, C5a, and ion binding pathways, which have been previously associated with immune function and inflammation. Further validation and investigation are required to confirm the identified genes and pathways before implementation in breeding programs.
PSX-2 Productive performance of Raramuri Criollo, Angus x Raramuri Criollo and Hereford x Angus cows in a low-input cow-calf system in northern Mexico
Authors: Floriano-López Adriana , Rodríguez-Almeida Felipe A , Martinez-Quintana Jose A A , Sandoval-Villalobos Jesus , Roacho-Estrada Octavio , Villareal-Balderrama José , Antillón-Ruiz Javier
Published: September 2024

Raramuri Criollo cattle (RC), a local heritage breed in the Chihuahua state of Mexico, are highly rustic and well-adapted animals that can contribute to cow productivity in a low-input cow-calf production system. The aim was to evaluate traits related to productive performance of purebred RC, Angus x RC (AC) and Hereford x Angus (HA) cows. Each cow breed group was randomly assigned to one of three pastures within each of two mountains dominant exposures and evaluated during 2022 and 2023 at Rancho Teseachi (28◦48′ N, 107◦25′ W) belonging to Universidad Autonoma de Chihuahua. The six grazing pastures ranged from 263 to 400 ha, with similar slope, altitude and water sources characteristics. The stocking rate was moderate (forage utilization <50%). Forage biomass availability for the period of use was sampled in October, and stocking rate adjusted accordingly in March. RC cows were bred with RC bulls, and AC and HA with Angus bulls. The breeding season was from September to November, and pregnancy diagnosis at mid-January. Non-pregnant cows were replaced by pregnant cows from other pastures of the same farm. Feed supplementation was limited in 2022 and according to nutritional requirements in 2023. Evaluated variables included calf birth (BW) and weaning weight adjusted (WW) to the average age at weaning (190 d in 2022 and 165 d in 2023); body condition score (BCS 1 to 9), cow body weight (CBW) at the beginning of the breeding season, as well as body weight of calf weaned by unit of cow weight (WW/CBW), and pregnancy rate (PR). A general linear model with fixed effects of breed group, sex, dominant exposure of mountains, their interaction, cow age subclass (Young, 4 yr; Middle, 5 to 8 yr; Adult, > 9 yr) and Julian date at calving as a covariate was adjusted using PROC GLM of SAS for continuous, normally distributed variables, and PROC CATMOD for pregnancy rate, leaving out sex and interaction effects. Means of BW and WW on calves from AC and HA cows were greater (P < 0.5) than those from RC cows in both years (Table 1). In 2022, the mean CBW of HA was greater (P < 0.5) than for AC, and this greater (P < 0.5) than for RC cows; BCS was greater for AC than for HA and RC, and PR lower (P < 0.5) for HA than for AC and RC. In 2023, there was no difference in CBW between AC and HA; BCS was similar (P > 0.05) among the three groups; and PR was the lowest (P < 0.5) for HA. The AC cows had the greatest WW/CBW mean (P < 0.5) in both years. Overall, using AC cows resulted on a combination of traits that outperformed on general productivity in the evaluated production system.
PSIII-26 Blood biochemistry, metabolomics profiling, and histology of contaminated with mycotoxin: Acute dose exposure 30 days-repeated toxicity study in piglets
Authors: Jeong Jin Young , Kim Minji , Kang Hwan Ku , Park Seol Hwa
Published: September 2024

Toxicity caused by deoxynivalenol (DON) and fumonisin (FB) produced by Fusarium species, naturally occur in food and feed, can lead to repress appetite and growth inhibition in pigs. Therefore, the purpose of this study was to investigate the effect of the mycotoxin exposure with different concentrations in liver, ileum, and rectum tissues of piglets. Animals fed binary mixtures of mycotoxins followed by 0.5, 1, and 3 mg/kg feed for 30 d. The castrated pigs (Landrace × Yorkshire) were housed one per separated pen. The tissue samples were collected for nuclear magnetic resonance analysis. Additionally, biochemistry and histology were determined. Final body weight (BW) showed significant differences between the control and nine differently treated groups. In the blood biochemical analysis, the absorption of mycotoxins was significantly increased blood urea nitrogen levels. However, decreasing lipase concentrations showed in binary mixture groups. Metabolomic profiles of liver tissue were more clearly separated based on orthogonal partial least square discriminant analysis than ileum and rectum tissues. The liver (Met, Pro, Lys, and Cys), ileum (Thr, Gly, Pro and Asp), and rectum (Met, Thr, and Pro) metabolic profile revealed the potential metabolites for mycotoxin exposure, respectively. Particularly, decreasing proline concentrations at high dose (3 mg/kg) showed in liver. Whereas, two organs observed an inverse trend. In the histological analysis, Group 9 (DON 3 plus FB1 3 mg/kg) might aggravate the fibrosis in liver tissue using Masson’s trichrome stains. Contaminated with acute doses showed no dramatical changes ileum and rectum tissue. Taken together, our results indicated that low dose (0.5 mg/kg) of mycotoxin did not result in significant differences. However, high dose (3 mg/kg) of mycotoxin induced significantly toxicity causing physiological changes. In conclusion, these results suggest that the toxicity of acute exposure to binary mixture cannot be ignored in piglets, because of their effects on the liver, ileum, and rectum.
PSIII-27 Blood biochemistry, histology, and metabolomic profiling of contaminated with mycotoxin: A repeated dose oral toxicity study in rats
Authors: Jeong Jin Young , Park Seol Hwa , Kang Hwan Ku , Kim Minji
Published: September 2024

Mycotoxins causes diseases and physiological responses in humans and livestock. This study was performed to estimate the effects of binary mixtures mycotoxin {e.g., deoxynivalenol (DON) and fumonisin (FB)] on blood biochemistry, histology, and metabolic profiles in rats fed with different toxin concentrations. Experimental animals were administered by oral gavage with 0.9% saline, DON (1, 5, and 10 mg/kg BW), FB (1, 5, and 10 mg/kg) at 8 wk of age. Histological changes, metabolomic profiling, and blood biochemical analysis were performed Masson’s trichrome stain kit, liquid chromatography mass spectrometry, and VetTest chemistry analyzer, respectively. The final BW of the rats contaminated with mixtures mycotoxin significantly decreased compared with the control group. Biochemistry results and fibrosis were also significantly differentially regulated according to mycotoxin concentrations. Additionally, we observed collagen fibers in the liver and kidney showed blue staining after toxin contamination. For metabolomic profiling, data were analyzed using MetaboAnalyst 4.0. Results were analyzed by multivariate analysis to elucidate the potential compounds. The toxin-treated groups observed discriminating metabolites in the liver and kidney tissue but no differences in ileum. The profiling revealed potential metabolites such as glycine, serine and threonine metabolism. Phosphatidylethanolamine and tryptophan were identified with high sensitivity as candidate biomarkers via variable importance in the projection plot in piglets fed with mycotoxin (FDR < 0.05; P < 0.05). The differently treated groups showed discriminating metabolites in different concentrations. In conclusion, these findings suggest that mycotoxin exposure disturbs histological changes and metabolites. Dietary toxins in rats may better understand the physiological effects consistent with metabolism, which are commonly reported in animals.
PSIV-22 Use of a mixture of olive pomace extract, a palatability enhancer and tributyrin as feed additive on the recovery of unweaned dairy beef calves with pneumonia at farm arrival
Authors: Marti Sonia , Devant Maria , Blanch Marta
Published: September 2024

Pneumonia is the main health issue that farmers have to fight when calves arrive at the rearing farm after marketing and transportation. Calves with pneumonia have a low intake impairing the recovery at arrival. The use of additives to enhance intake and immunity at arrival could be a strategy to minimize those negative effects. A total of 36 calves [body weight (BW) = 71.3 ± 2.83 kg] with pneumonia (ultrasound lung score ≥ 3) arriving at a commercial farm after marketing and transportation were used to evaluate the effect of a mixture of feed additives (FA) comprising a palatability enhancer, standardized olive pomace extract and tributyrin on performance in calves fed 2 L of MR twice daily at 12.5% and ad libitum concentrate feed. Calves were allocated in 4 pens and distributed in 2 treatments (2 pens/treatment); calves fed a concentrate feed without FA since the beginning of the study (arrival to the rearing farm after transport) until weaning (CT; n = 18); calves fed a concentrate feed containing the mixture of FA (CM; n = 18) from arrival until weaning. Calf BW and pen intake were recorded weekly. On d 21 of the study, calves were partially weaned and only milk replacer was offered in the morning, and on d 28 all calves were completely weaned. The study lasted 35 d. Data were analyzed with a mixed-effects model. Final BW of CM calves (95.9 ± 1.29 kg) tended to be greater (P = 0.08) compared with BW of CT calves (92.7 ± 1.29 kg). The CM calves tended (P = 0.06) to have greater ADG than CT calves (0.70 ± 0.037 kg/d and 0.61 ± 0.037 kg/d, respectively). However, a greater sample size may be necessary to observe differences in average concentrate intake measured by pen between treatments (0.82 ± 0.033 kg/d and 0.87 ± 0.033 kg/d for CT and CM, respectively). These results highlight the potential of using a mixture of feed additives with olive pomace extract, palatability enhancers, and tributyrin on the performance recovery of calves with pneumonia on arrival at the rearing farm.
PSIV-15 Effect of transient fetal bovine viral diarrhea virus infection on postnatal growth, estimated dry matter digestibility, glucose concentrations, and carcass characteristics
Authors: Miller Alexandra C , Loh Huey Yi , Chek Erlene , Guimaraes Octavio , Thomas Tyler A , Thorndyke Meghan P , Van Campen Hana , Kincade Jess N , Hansen Thomas R , Engle Terry E
Published: September 2024

Fetal infection of bovine viral diarrhea virus (BVDV) before d 125 to 150 of gestation results in the birth of immunotolerant, persistently infected (PI) calves. Infection of BVDV during late gestation results in transient fetal infections (TI). Unvaccinated, yearling Hereford heifers (n = 25), seronegative for antibodies to BVDV1 and BVDV2, were bred by artificial insemination with X chromosome-bearing sperm from an Angus sire to examine the impact of TI on postnatal growth, estimated dry matter digestibility, blood glucose concentrations, and carcass characteristics. On d 175 of pregnancy, heifers were intranasally inoculated with either DMEM + 2% horse serum (sham control) to generate control calves or 4.0 log TCID50 noncytopathic type2 BVDV to generate TI calves. All sham-inoculated control dams remained seronegative, and all BVDV-inoculated dams seroconverted by d 14 post-inoculation. Sham-inoculated control dams (n = 12) and BVDV-inoculated dams (n = 12) gave birth to live calves. All control offspring were seronegative, and all TI offspring were seropositive for antibodies to type 2 BVDV at birth. All offspring were raised on pasture until weaning. At weaning, all calves were transported to our feedlot research facility, housed in one group feedlot pen, and transitioned to a high-energy concentrate-based diet until reaching an approximate BW of 600 kg. Upon arrival at the feedlot, all animals received a standard heifer growth implant, a modified live viral vaccine containing IBR-BRSV-PI3 and were dewormed. Heifer BW and jugular blood samples were collected every 28 d. On d 84 of the feeding period, titanium dioxide was added to the diet of 12, age-paired, individually fed, heifers (3 control and 3 TI heifers; approximately 1 yr of age) for 28 d and used to estimate dry matter digestibility. After approximately 280 d on feed heifers were transported to a USDA-inspected abattoir and harvested. The TI heifers had lighter birth weights (P < 0.03) and final BW (P < 0.04) when compared with control heifers. Average daily gain was greater (P < 0.01) in control compared with TI heifers. Blood glucose concentrations were similar between control and TI heifers at all sampling time points. Dry matter intake of individually fed heifers was similar across treatments. TI heifers had a 2.2% lesser (P < 0.05) dry matter digestibility and lighter (P < 0.01) hot carcass weights compared with controls. These data suggest that TI fetal BVDV infection negatively impacts growth throughout the feeding period, possibly by impacting gastrointestinal tract function. This research was supported by USDA-NIFA Grant # 2019-67015-29866.
PSIV-17 Studies on diarrhea and growth performance of early weaned piglets after supplementation with quebracho tannin product, MGM-P
Authors: LI Junyou , MA Min , ENOMOTO Yuriko , TAKAHASHI Tomotsugu , UCHIDA Kazuyuki , CHAMBERS James K , Kuwahara Masayoshi , TAKAHASHI Shin-Ichiro
Published: September 2024

The objective of this experiment was to explore the feasibility of supplementing diets of early weaned piglets with 0.5% and 1.0% MGM-P (quebracho tannin product) as an alternative to antibiotics. Weaned (n = 36) piglets were allotted to one of four groups and given the basal diet (NC), as well as the basal diet containing 0.5% (LT), 1.0% (HT) MGM-P, and antibiotics (PC), respectively. Diarrhea, growth performance, hematology, blood biochemistry and blood amino acid concentrations were monitored during feeding. 3 piglets per group were slaughtered after the experiment to assess organ index.
PSIV-19 The use of microencapsulated zinc oxide improves the growth performance and intestinal health of newly weaned piglets
Authors: Babatunde Olufemi O , Tactacan Glenmer B , Vieira Marcia S , Lahaye Ludovic , de Moraes Mariana L
Published: September 2024

The application of microencapsulation technology to protect zinc may support inclusion of reduced levels with similar benefits to elevated doses of free zinc oxide. This study aimed to compare the effects of different doses of a microencapsulated ZnO (Zinco-Plus S) and free ZnO in nursery diets on growth performance and intestinal health of pigs. A total of 480 newly weaned piglets [26 d of age, initial body weight (BW) = 7.39 kg] were randomly assigned to one of four dietary treatments for 35d. Treatments were as follow: free ZnO (3,000, 1,500, and 0 ppm at phase 1, 2, and 3, respectively) or one of three doses of the microencapsulated ZnO (400, 600, and 800 ppm) maintained consistently across all 3 nursery phases (total amount of zinc in diets were within limits allowed by Canadian regulation). Each dietary treatment had 10 replicates, with 12 pigs/pen, gender balanced. All treatments had protease (Jefo Protease; 125 g/t), xylanase (Belfeed Xylanase; 100 g/t) and protected organic acids and essential oils (Porcinat+; 2 kg/t in phase 1 and 2, 1 kg/t in phase 3). Body weight, BW gain and feed intake were measured to determine feed conversion. At the end of phase 1, fecal sample was collected (pooled of 4 samples/pen) to determine zinc excretion. At the end of phase 2, blood serum was collected (1 pig/pen) to measure calprotectin and diamine oxidase concentrations and, ileal tissue was collected (1 pig/pen) to measure expression of zonular occludens (ZO) -1. Data were submitted to ANOVA and Fisher test with significance set at P < 0.05. There was no difference (P > 0.05) in final BW of pigs across all treatments. Nonetheless, piglets receiving 800 ppm of the microencapsulated ZnO had improved (P < 0.05) feed conversion ratio compared with pigs fed diet containing free ZnO. There was no difference (P > 0.05) in serum concentrations of calprotectin and diamine oxidase across all treatments, indicating improved intestinal health regardless of the form of ZnO. Piglets supplemented with microencapsulated ZnO at 800 ppm had an increased (P < 0.05) intestinal expression of ZO-1 in comparison with piglets receiving free ZnO, indicating better intestinal integrity. Fecal zinc concentrations were reduced (P < 0.05) by 75 % with the inclusion of microencapsulated ZnO compared with free ZnO. Piglets supplemented with microencapsulated ZnO at 800 ppm improved (P < 0.05) feed cost per kg BW gain by 10.7 % when compared with free ZnO. These findings show that supplementing lower levels of zinc in nursery diets via microencapsulation technology improves growth performance and supports intestinal health at levels comparable with increased free ZnO supplementation. Moreover, the utilization of microencapsulated zinc oxide has the additional advantage of minimizing environmental impact through the reduction of zinc wastage.
PSI-23 Growth implants can decrease enteric methane emissions intensity from finishing beef cattle
Authors: Swenson Maya , Place Sara E
Published: September 2024

Growth promotants are a useful tool in cattle production to improve their environmental impact by decreasing emissions per unit of gain and increasing overall feed efficiency. The objective of this study was to assess the relationship between enteric methane emissions, feed intake, average daily gain (ADG), and feed efficiency of implanted and nonimplanted finishing steers. Cattle (n = 62) were housed at the Climate Smart Research pens at Colorado State University and blocked by body weight (BW) into two pens and randomly assigned to treatment. Each pen was equipped with GreenFeed automated head chambers and SmartFeed feed intake measurement (C-Lock, Rapids City, SD). The study was a completely randomized block design. Animals within each block were then randomly assigned a treatment: implanted with Component TE200 (IMP; Elanco Animal Health, Greenfield, IN) or not implanted (CON). Enteric emissions, dry matter feed intake, BW, and BW gain (ADG) were collected from each individual animal from the light and heavy blocks for 80 and 52 d, respectively. Data were analyzed in JMP Pro with the linear model function and significance was declared a P ≤ 0.05. IMP cattle had a greater average ADG (2.40 kg/d vs 1.77 kg/d, P < 0.0001) compared with CON cattle. A difference was observed in total methane (CH4) emissions between treatments (200.83 g CH4/d IMP and 187.45 g CH4/d CON, P = 0.02). Dry matter intake (DMI) was not different between treatments (P = 0.17). Methane emissions intensity for each treatment was 84.89 (IMP) and 106.90 g/kg of ADG (CON) was different (P = 0.0002), while CH4 yield (CH4 per kg of DMI) was not different (P = 0.12). Overall feed efficiency between treatments resulted in IMP animals having a greater feed efficiency (4.74 kg DM/kg ADG) compared with CON animals (6.32 kg DM/kg ADG, P < 0.0001). In summary, growth promotants decrease CH4 emissions intensity in finishing steers and increase animal feed efficiency without affecting daily DMI.
PSI-10 Evaluation of factors influencing conception rate within a fixed-time artificial insemination protocol using sex-sorted semen
Authors: Efird Emily E , Powell Jeremy G , Looney Charles R , Perkins Tommy L
Published: September 2024

Sexed semen artificial insemination is a reproductive technology that allows producers to enhance genetics through use of superior sires, control gender of offspring, and increase profitability. However, sexed semen practices have yet to be widely used within the beef cattle industry due to reduced conception rates, decreased sperm cell numbers in comparison with conventional semen, and increased costs. The objective of this study was to determine the effects of time of estrus, time of insemination, sire, weight, and age on pregnancy rates within a fixed-time artificial insemination (FTAI) protocol using two fixed-time inseminations and female sex-sorted semen from three sires (SexedULTRA 4M, STGenetics, Navasota, TX). Multiparous commercial beef cows (n = 130) were randomized into synchronization protocol and sire treatments by age, body condition score (BCS), and days post-partum at the University of Arkansas Savoy Research Complex in Fayetteville, AR. Synchronization treatments included the 8&6 Synch protocol using two FTAI times: 66 h or 72 h post-CIDR removal. Each synchronization treatment used a controlled internal drug releasing device (Eazi-breed CIDR; 1.38g progesterone, Zoetis, Kalamazoo, MI) inserted intravaginally -14 d of the protocol simultaneous to administration of prostaglandin F2α (PGF; 25mg dinoprost tromethamine; Lutalyse HighCon, Zoetis). In both treatments (66 h) and (72 h), gonadotropin-releasing hormone (GnRH; 100µg gonadorelin; Factrel, Zoetis) was administered on d -6. Each treatment was then administered PGF simultaneous to CIDR removal on 0 d, 66 ± 2 h prior to FTAI within the 66 h treatment, and 72 ± 2 h prior to FTAI within the 72 h treatment and final administration of GnRH. Standing heat (estrus) was visually detected every 3 h for 30 min intervals between the time of CIDR removal and FTAI. Estrotect patches (Rockway Inc., Spring Valley, WI) were used in conjunction with visual detection. Time of estrus was signified as time of solid footing while standing to be mounted in combination with presenting a patch score of 4 (>75% color rubbed off). Pregnancy rates (PR) were determined via ultrasound 42 ± 1 d after FTAI. PR were analyzed by time of estrus (TE), fixed-time insemination protocol (TRT), age, and body weight using the GLIMMIX procedure on SAS 9.4 (SAS Institute Inc., Cary, NC). There were no significant effects on PR by age or body weight. TE (P = 0.30) and TRT (P = 0.28) were also found to be non-significant. TE was divided into 4 time groups at < 11 h, 11.01-22 h, >22.01 h (hours prior to FTAI), or non-estrual; resulting in PR of 53 %, 74 %, 50 %, and 64 % respectively. In conclusion, data collected suggests acceptable pregnancy rates may be achieved within a fixed-time artificial insemination protocol using sexed semen regardless of age, weight, synchronization treatment, or time of estrus.
PSI-3 Effects of a Retinoid X Receptor agonist on primary ovine satellite cells
Authors: Blad Taya J , Wanguba Amy S , Rojas-Reyes Jesus A , Cariaga Amaia , Rivera Courtney , Odani Jenee S , Reichhardt Caleb C
Published: September 2024

Sheep producers are typically paid based on body weight, so understanding the mechanisms of postnatal skeletal muscle growth is vital. Satellite cells are responsible for the capacity for postnatal skeletal muscle growth. Satellite cells proliferate and then differentiate into myoblasts before fusing with existing myotubes. The retinoid X receptor (RXR) is a transcription factor that enhances myogenic differentiation 1 (MyoD) expression, which increases differentiation and fusion of myoblasts in sheep. LG 100268 is an RXR agonist, which activates the RXR. The objective of this project is to measure the effect of LG 100268 on primary ovine satellite cell (OSC) proliferation and protein synthesis rates. Primary OSC were isolated from the hind legs of 9-mo old commercial hair sheep wethers (n = 3). For proliferation, cultures were grown to approximately 70% confluency, followed by treatment with 5% fetal bovine serum (FBS) or 300 nM of LG 100268 in 5% FBS. For protein synthesis, cultures were grown to approximately 80% confluency, at which point cultures were induced to differentiate and treated 48-h later with serum free media (SFM) or 300 nM LG 100268 in SFM. Proliferation rates were measured at 24-h post-treatment, and protein synthesis rates were measured at 6-h post-treatment. Treatment with 300 nM LG 100268 increased (P = 0.004) OSC proliferation rates compared with control cultures. Preliminary protein synthesis results suggest that LG 100268 does not alter (P = 0.22) protein synthesis rates of fused OSC. However, more research is warranted to clarify the role of the RXR in sheep skeletal muscle growth.
PSI-15 Validation of a rapid test to evaluate humoral immunity in Labrador Retrievers across multiple life stages
Authors: McCracken Fiona B , Dickerson Sarah M , Skaggs Patrick M , Timlin Claire L , Fowler Jason W , Coon Craig N
Published: September 2024

This study sought to validate the D2Dx rapid immunity test in canines and investigate the age-related changes in the humoral immune system of healthy large breed dogs. Blood plasma with EDTA anticoagulant was collected from healthy Labrador Retrievers (n = 80) housed at Four Rivers Kennel under IACUC protocol FRK-56. Age groups were defined as follows: puppy 0-1.5 yr, adults 1.5-7 yr, senior 7-10, and geriatric 10-14. Immunity biomarkers including c-reactive protein (CRP), interleukin 4 (IL-4), interferon gamma (IFN-γ), complement protein 3 (C3), and immunoglobulin G (IgG) were determined through canine specific enzyme-linked immunosorbent assay (ELISA) kits. The nanoparticle based D2Dx test, which evaluates the cumulative humoral immune response, was also performed. Data were analyzed using a one-way ANOVA between age groups, with a Tukey’s post hoc, and correlations between variables were evaluated through multivariate analysis. The D2Dx score was correlated with body weight, age, IgG, and C3 validating that the test was able to adequately measure the humoral immunity in canines (r ≥ 0.49). D2Dx score was significantly different between age groups (P < 0.01) with puppies having significantly reduced scores compared with all other groups (P < 0.01). C3 was significantly different between age groups (P < 0.01), with puppies significantly less than other life stages (P ≤ 0.03). The C3 of adults averaged significantly greater than seniors and trended greater than geriatric subjects (P ≤ 0.01, 0.07). IgG between ages was also significantly different, with puppies significantly less than other age groups (P < 0.01). There was no significant difference between age groups for IFN-γ, IL-4 ratio, IFN-γ, IL-4, or CRP (P ≥ 0.18). This study showed that the D2Dx Rapid Immunity Test is able to detect changes to humoral immunity in canines. Beyond evaluating the effectiveness of the D2Dx test, this study also provides important information about the under researched topic of canine humoral immunity development and senescence in a robust, healthy cohort of large breed dogs.
PSI-1 Genetic and non-genetic factors influencing beef cattle attractiveness to horn fly
Authors: Alvares Luana , Shannon Elizabeth A , Blake Nicole B , Cone Fred M , Meyer Grace , Santacruz Valentina E , Scullin Paige R , Brown Olivia G , Cavender Castle J , Ladeira Giovanni C C , Rezende Fernanda M M
Published: September 2024

Horn flies are the most common summer pests of cattle, leading to substantial economic losses due to impaired production and decreased animal welfare. Genetic and non-genetic factors have been reported to influence cattle susceptibility to horn flies. However, the wide range of heritability estimates, and few identified genomic regions associated with cattle resistance to horn fly may be due to subjective assessment in collecting the fly load phenotype and the small size of the population assessed. Here, beef calves from the UF purebred Brahman (BRA) and Multibreed Angus-Brahman (MAB) populations were video recorded at weaning using a GoPro camera mounted on the top of the chute. Fly infestation was determined as the average fly count obtained from five longitudinal images of each animal using ImageJ software. A total of 748 crossbred and 415 purebred calves born from 2021 to 2023 were evaluated during summer (August or September). Analysis of variance (ANOVA) was performed within herd by fitting linear models that included collection date, age, skin color, coat color, and pre-weaning average daily gain (ADG) as fixed effects, and residual as a random effect. For MAB calves, breed groups (BG) determined based on the percentage of Brahman breed, with BG1 ranging from 0 to 19%, BG2 from 20 to 39%, BG3 from 40 to 59%, BG4 from 60 to 79%, BG5 from 80 to 100%, were also fit in the model. Fly count was transformed to a natural log value (log[count +1]) ensuring normally distribute residuals. As expected, darker colors were significantly more attractive to horn flies, while animals with greaterr percentage of Brahman were less susceptible than animals with greater percentage of Angus breed. Considerable variability in fly load was observed within purebred Brahmans, indicating that additional genetic factors, other than breed, influence cattle resistance to flies. Positive estimates were observed between horn fly load and average daily gain in both herds, which can be due to the fly load below the previously reported economic injury level of 200 flies (BRA: 28.78 ± 38.20, MAB: 19.31 ± 26.72). Variance components were estimated within herds by fitting the same aforementioned effects and a genomic-based relationship matrix (G) constructed with genotypes from the GeneSeek Genomic Profiler F250 SNP chip. The moderate heritability estimate demonstrates the feasibility of selecting cattle resistant to horn flies. Overall, our findings have the potential to contribute to reducing losses and costs in beef cattle operations, while reducing the impact on the environment of overuse of insecticides.
PSI-16 Evaluation of protein quality of defatted black soldier fly (Hermetia illucens) larvae meal compared with traditional protein sources for dogs and cats
Authors: Mioto Julio , Utterback Pamela L , Parsons Carl M , Madison Sean , Adolphe Jennifer , de Godoy Maria R C
Published: September 2024

There is increased interest in the use of insects, such as black soldier fly (Hermetia illucens) larvae meal (BSFLM), as an alternative protein source in pet foods. However, additional information is needed to determine how BSFL protein quality compares with traditional pet food protein sources. Thus, the objectives of this study were to determine the chemical composition, amino acid digestibility, and protein quality of defatted BSFLM in comparison with whole egg powder (WEP) and chicken meal (CM) using the precision-fed cecectomized rooster assay. Fifteen cecectomized roosters (n = 5 per substrate) were randomly allocated to the test substrates BSFLM, CM, and WEP. After 26 h of feed withdrawal, 20 g of substrates were crop-fed and excreta were collected for 48 h. Digestible indispensable amino acid score (DIAAS)-like values were calculated using the Association of American Feed Control Officials (AAFCO), The European Pet Food Industry Federation (FEDIAF), and National Research Council (NRC) reference values for different life stages of dogs and cats. Data were analyzed using SAS Proc Mixed 9.4 with P ≤ 0.05 significance. On a dry matter basis, CM had the greatest crude protein (70.2%), followed by BSFLM (59.8%), and WEP (51.2%). In general, WEP had greater amino acid digestibility than BSFLM and CM. BSFLM (84%) and CM (84%) had comparable arginine digestibility, but less than WEP (92%). Lysine digestibility was greater for BSFLM (80%) in contrast with CM (74%), but less than WEP (91%). DIAAS-like values were calculated, revealing methionine + cysteine as the first limiting amino acids for growing puppies and adult dogs in BSFLM according to AAFCO, FEDIAF, and NRC, whereas for CM threonine was the first limiting amino acid based on AAFCO, and phenylalanine + tyrosine based on NRC and FEDIAF. NRC identified methionine and cysteine as limiting for all test substrates in adult dogs. Methionine and cysteine were limiting for growing kittens for BSFLM among AAFCO, FEDIAF, and NRC. For CM and WEP, phenylalanine and tyrosine was the first-limiting amino acid by NRC and FEDIAF. For adult cats, phenylalanine and tyrosine were the limiting amino acid for BSFLMand CM according to AAFCO and FEDIAF, with NRC identifying it as limiting across all protein sources. In summary, methionine and cysteine and/or phenylalanine and tyrosine were the primary limiting amino acids among the protein sources evaluated. In general, BSFLM had comparable indispensable standardized amino acid digestibility to CM.
PSI-17 Anti-endotoxin immunoglobulin (Ig) Y time course of oral passive transfer and impacts on growth performance in foals
Authors: Mork Mckenzie J , Conrad Matthew B , Trauner Alexis , Hull Jason , Hawkins Michelle , Robley Brian , Larson Phillip , Bradbery Amanda N
Published: September 2024

Foal diarrhea is the leading cause of morbidity in neonatal foals and is often caused by various environmental pathogens. The adaptive immune system of foals depends on postpartum Ig absorption from maternal colostrum. To date, there lacks an easy way to supplement the immune system before intestinal closure. Thus, an anti-endotoxin IgY supplement derived from hyperimmunized hens may provide pathogen-specific protection if successful in passive transfer. Therefore, the objective was to determine the effects of an oral anti-endotoxin IgY on growth, stress, and passive transfer in neonatal foals with the hypothesis that IgY would successfully cross the gut barrier, positively impact growth, and ameliorate stress. To test this, Quarter Horse foals (n = 11) were randomly assigned based on foaling date to one of two treatment groups for a 28-d trial. Upon signs of impending parturition, mares were moved to box stalls (3.7 × 7.3 m) and parturition was attended. At birth, foals were assigned to either the control (CON; n = 5) or treatment group (TRT; n = 6). Foals assigned to TRT were supplemented with 40 g egg-derived anti-endotoxin IgY oral supplement (Camas, Inc.) dissolved in 50 mL ddH20 at 20 min after nursing and again at 12 h postpartum. The CON foals received isovolumetric ddH2O. Beginning at h 24, and daily thereafter, TRT foals received 1 g egg-derived anti-endotoxin IgY diluted in 5 mL ddH2O. Blood samples were collected from foals prior to nursing at h 0 and following the first oral treatment at h 2, 6,12, 24 and d 3, 7, 14, 21, 28. Harvested serum was analyzed for IgG, IgA, IgY, and cortisol by commercial ELISA. Data were analyzed using PROC MIXED in SAS v9.4 with repeated measures of time. Vital signs were similar for all foals regardless of treatment (P > 0.24) and all growth parameters increased over time (P < 0.01). There tended to be a treatment × time interaction for wither height (P = 0.10) where TRT wither height was greater at d 28 (P = 0.07). There was a treatment × time interaction (P < 0.01) for serum IgY concentrations where CON foals had undetectable concentrations for the duration of the study and TRT foals peaked on d 7 with detectable l concentrations remaining on d 28. Cortisol, however, was not influenced by treatment (P > 0.29), and IgG and IgA concentrations were only influenced by time (P < 0.01). In conclusion, despite having no effect on vital signs and stress, IgY is passively absorbed following oral administration to neonatal foals without negatively impacting the passive transfer of maternal IgG or IgA, lending to future work on pathogen-specific protection against foal diarrhea.
PSIII-9 Cannabinoid uptake and depletion in blood plasma of cattle fed hemp leaves
Authors: Fruge Greyson , Magnin Geraldine , Kleinhenz Michael , Jessup Russell , Bruner Brian , Drewery Merritt L
Published: September 2024

Recent legislation classified hemp (Cannabis sativa L.) as a non-drug type form of Cannabis sativa that can be legally cultivated if tetrahydrocannabinol (THC) remains < 0.3%. As such, hemp has been classified as an agricultural commodity and production in the United States has increased. Hemp cultivation produces fibrous by-products, such as hemp leaves, that are not utilized for human needs and have potential as livestock feed, especially for cattle. However, the presence of cannabinoids in hemp by-products [e.g., THC and cannabidiol (CBD)] has restricted hemp as feed for livestock due to the potential for cannabinoid retention in tissues. The objective of this study was to determine the uptake and depletion profile of circulating cannabinoids in cattle fed hemp. Ruminally cannulated beef steers (n = 5) consuming forage were utilized in a trial involving a 10-d adaptation period, two 14-d periods during which intake and digestion were measured, and a 45-d monitoring period for tissue collection. Only data related to plasma are presented here. Hemp (cultivar Cherry Wine) was cultivated from May to August 2023, air dried, and manually stripped of leaves. In period 1, steers were fed ad libitum hay and supplemented alfalfa cubes at 0.2% body weight (BW). In period 2, steers received the same diet but were also supplemented hemp leaves at 3.9 mg/kg BW of cannabidiolic acid (CBDA) daily. Blood samples were collected via jugular venipuncture using an 18-gauge needle. Time points for collection in period 2 were 0, 2, 4, 6, 8,12, 36, 48, and 72 h after initial hemp introduction. Time points for collection in the monitoring period were 24, 48, 72, and 96 h after hemp was no longer offered. After collection, blood samples were centrifuged at 1500 x g for 10 min and plasma was analyzed for cannabinoids via ultra-performance liquid chromatography mass spectrometry (UPLC-MS/MS). Several cannabinoids [i.e., CBDA, cannabidivarnic acid (CBDVA), tetrahydrocannabivarnic acid (THCVA), and tetrahydrocannabinolic acid (THCA-A)] were present in plasma at detectable levels 2 h after initial hemp consumption and remained present 96 h after cessation of hemp consumption. THC was not detected in plasma; however, THCA-A, the precursor for delta-9 THC, was present 2 h after hemp was introduced (1.2 ng/mL), reaching peak concentrations at 72 h (20.4 ng/mL), and remained present 96 h after hemp was last consumed (2.8 ng/mL). CBD was detected 36 h after hemp introduction (1 ng/mL) and remained present 96 h after cessation of hemp (0.9 ng/mL) with peak concentrations 24 h after cessation of hemp consumption (3.3 ng/mL). These data indicate cattle consuming hemp rapidly uptake cannabinoids into circulation and these cannabinoids remain present for at least 96 h after hemp consumption ceases. These data provide a foundation for establishing a withdrawal period for hemp in cattle.