bluuebunny/crossref_metadata_2025 huggingface dataset:
PSI-24 Acute and chronic stress response following weaning and transportation in the average piglet
Authors: Turner Isabel , Smith Alyssa A , Rudy Kaylyn , Jeon Dayeon , Richert Brian T , Pasternak J Alex A
Published: September 2024

The American swine industry relies on a model where facilities for farrowing are often geographically isolated from those used later for wean-finish, which necessitates multiple coincident stressors including weaning, mixing, transportation and feed/water restriction. Previous studies indicate this combined stress reduces subsequent growth performance; however, the specific impact of each stressor on an average, objectively healthy piglet is not well understood, nor is the acute physiological response to this life event. The objective of this study was to determine the effect these stressors on thyroid function, intestinal health, and body weight (BW) in average, healthy pigs. In this study, a total population of 588 piglets were weighed the day prior to weaning and 230 piglets with the lowest Z-scores for BW were selected (5.74 ± 0.70 kg). Piglets (n = 70) were weaned directly into nursery pens and provided with feed and water, 70 were transported for 10 h with no access to feed and water, and 70 were grouped together into 2 large pens with no access to feed and water for an equivalent 8 h period. The remaining 20 piglets were not weaned and served as an unstressed control group. A total of 10 pigs from each group were euthanized at 32 and 56 h post-weaning for tissue sampling. Ileal villi height, crypt depth, and goblet cell numbers were measured, and no treatment effects observed (P > 0.05). Serum triiodothyronine (T3) concentrations were measured pre-treatment (t = 0), 24 h (t = 24), 48 h (t = 48), and immediately following euthanasia (t = 32 or 56 d). There were no significant differences in serum T3 among treatments at t = 0. At all-time points post stress event, control piglets had greater T3 concentrations compared with feed restricted (P < 0.05) and transported (P < 0.05) pigs. Weaned pigs at t = 32, t = 48, and t = 56 had decreased T3 concentrations (P < 0.05) and weaned pigs tended (P = 0.0584) to have decreased t = 24 T3 concentrations compared with pigs remaining with the sow. The remaining pigs (n = 50) per weaning group were weighed weekly throughout the nursery phase and every 3 wk in the grow-finish phase to determine the impact of each stressor on growth. There was no significant effect of weaning treatment on BW at any time point (P > 0.10). Carcass data including carcass weight, loin and backfat depths, and lean percentage were measured at time of slaughter with no significant differences found among groups (P > 0.60). As no effect on growth weight or carcass characteristics were observed between treatment groups in average pigs, this suggests that it may be beneficial to transport average pigs the longest distance, while minimizing transport for pigs on either end of the weaning weight spectrum. Further research is needed to compare effects of weaning and transportation stressors on average and weight extremes of weaned pigs.
PSIII-21 Variation in mitochondrial genes involved in oxidative phosphorylation in cattle
Authors: Seier Lauren E , Batt Mackenzie C , Fuller Anna M , Yates Dustin T , Montooth Kristi , Petersen Jessica L
Published: September 2024

The mitochondrion is a maternally inherited organelle that produces approximately 90% of cellular energy. The mitochondrial genome (mtDNA) consists of 13 genes that are critical components of oxidative phosphorylation. Identifying and understanding variation within this genome could elucidate differences in metabolic and physiological traits, specifically growth efficiency in cattle. Our aim is to identify how variation in the mitochondrial genome influences efficiency in beef cattle. Low-pass sequencing data (average 0.5X coverage of the autosomes) were collected (Neogen) from 49 animals within the UNL herd (composite Simmental, Red Angus, and Gelbvieh). The data were trimmed and mapped (BWA-MEM) to the ARS-UCD1.2 cattle genome. After variant impacts were predicted (Ensembl VEP) haplotype networks were created to visualize variation among samples. Over 60X coverage was achieved across the mitochondrial genome, on average. Excluding the D-loop, 62 variants were identified in the 49 animals: 2 tRNA, 6 rRNA, and 54 coding single nucleotide polymorphisms (SNPs). These 62 variants were encompassed in 23 unique haplotypes. Of the coding variants, 13 were nonsynonymous and found in the following genes encoding components of oxidative phosphorylation: ND1 (n = 3), ND2 (n = 1), ND3 (n = 1), ND4 (n = 1), ND5 (n = 1), ND6 (n = 3), COX3 (n = 2), and CYTB (n = 1). Nine unique haplotypes were present considering only nonsynonymous variants. Nonsynonymous mutations were identified in complex I genes (ND1-6), in the complex IV gene COX3, and in CYTB, which is involved in multiple processes including the electron transport chain. These data, from a closed herd at UNL, support that there is a great deal of mtDNA variation present among beef cattle for which to analyze the impact of mitochondrial genotype on animal efficiency. Performance data demonstrate variation in average daily gain (ADG) and residual feed intake (RFI) in this herd, with a mean ADG of 1.95 kg/d (SD = 0.23 kg/d) and a mean RFI of -0.11 kg (SD = 0.57 kg). Data on individual feed intake, growth rates, and carcass performance values will continue to be collected on all animals sequenced. Based upon these data we hypothesize that variation in the mitochondrial genome will be associated with altered complex I and IV activity. For a more comprehensive understanding of this variation, the sample size will be expanded to over 1,500 animals in the next 2 yr. Overall, from our initial analysis of the mitochondrial genomes from 49 animals, we have identified 62 variants that we anticipate will explain variation in cellular and growth efficiency.
PSIII-23 Identifying genes associated with the retinol biosynthesis pathway in corpora lutea of cyclic and pregnant gilts
Authors: Stuehr Matthew D , Poole Rebecca K , Wiegert Jeffrey , Hickman-Brown Kyle J , Bazer Fuller
Published: September 2024

Improving reproductive performance (e.g., farrowing rate, litter size, pigs weaned) of commercial sows is crucial for sustainability of swine production. Good nutrition is essential to support high performing reproductive outputs. Vitamin A (retinol) is an essential fat-soluble vitamin with important roles in tissue development and reproduction. Previous studies in porcine luteal cells in vitro have shown that retinoids support corpus luteum (CL) function and stimulate progesterone (P4) secretion. The objective of this study is to identify the expression of genes associated with retinol biosynthesis pathway in CL of cyclic and pregnant gilts. Duroc x Landrace x Yorkshire gilts (n = 37) free of physical, heath, or reproductive-related issues were housed in groups on solid concrete floors with ad libitum water access and fed 2.0 kg/d of a standard gestation diet formulated to meet micronutrient requirements. After breeding, gilts were euthanized and ovariohysterectomized during the preimplantation (d 11; n = 10), implantation (d 15; n = 10), mid gestation (d 60; n = 6), and late gestation (d 00; n = 6) stages of pregnancy, as well as cyclic gilts (d 15 of luteal phase; Cyclic;n = 5). Both ovaries of each gilt were separated from the uteri and CL count was recorded before storing at -80°C. Blood was collected concurrently, centrifuged at 2,500 x g for 25 min at 4°C, and resulting plasma was stored at -20°C. Plasma P4 concentration was quantified using a double-antibody RIA kit per manufacturer instructions. Mean relative expression of CL aldehyde dehydrogenase 1 family member 1A (ALDH1A1) was quantified by RT-qPCR. Statistical analyses for CL number and P4 concentrations were determined by PROC GLM in SAS 9.4 and gene expression comparison by day was determined by one-way ANOVA and Student’s t-test for pairwise comparison in JMP 17.0. There were no differences in CL number (15.7 ± 1.5; P > 0.05) or P4 concentrations (17.3 ± 5.3 ng/mL; P > 0.05) by day of pregnancy or between cyclic and pregnant gilts. The mean relative expression of ALDH1A1 was greater (P < 0.001) between d 11 and Cyclic gilts and between d 11 and all other dys of pregnancy (P < 0.01). However, there were no other statistical significances for ALDH1A1 between day of pregnancy or by pregnancy status (P > 0.05). The greater mean relative expression of ALDH1A1 at D 11 of pregnancy could be evidence that retinoic acid has an important role in the porcine anti-luteolytic mechanism, which occurs around d 11 of pregnancy in pigs, and is crucial for the maintenance of pregnancy. Other genes associated with the retinol pathway like retinol binding protein 2 (RBP2), retinol binding protein 4 (RBP4), lecithin retinol acyltransferase (LRAT), and alcohol dehydrogenase 1C (ADH1C) will be quantified by RT-qPCR to better understand the role of retinol biosynthesis in porcine CL function.
PSIII-20 The effects of vitamin E and/or C on parasite burden in hair sheep
Authors: Rojas-Reyes Jesus A , Blad Taya J , Wanguba Amy S , Bulosan Janae S , Odani Jenee S , Reichhardt Caleb C
Published: September 2024

Anthelmintic resistance in flocks is an occurring issue for small ruminant producers due to increasing gastrointestinal nematode (GIN) infections. Prevalence of high virulence GINs decreases immunity and growth, therefore not making anthelmintics economically sustainable for producers. In this current research study, we examined the role of vitamins E and/or C supplemented to crossbred hair sheep (Dorper, Katahdin, Barbados crosses) on parasite burden over time. The hypothesis of this research was that supplementing vitamin E and/or C will work comparable to anthelmintic treatment to control GIN in hair sheep. Mature ewes (n = 30) were stratified based on FAMACHA score. Ewes were placed into one of five treatment groups: 1) no dewormer or vitamin treatment (CON; n = 6), 2) anthelmintic treatment (Levamed; 0.08mg/kg; Bimeda Animal Health, Schaumburg, IL; n = 6), 3) combination of vitamin E and vitamin C (Vitamin E300; 0.33IU/kg of body weight (BW) administered subcutaneously; Durvet Animal Health; Blue Springs, MI; Vitamin C; Orally drenched at 0.56 mL/kg of BW; Radix Laboratories; Eau Claire, WI; n = 6), 4) vitamin C (Vitamin C;0.56 ml/kg of BW; Radix Laboratories; Eau Claire, WI; n = 6), and 5) vitamin E (Vitamin E 300; 0.33 IU/kg of BW; Durvet Animal Health; n = 6). Growing lambs (n = 30) were also placed into the same treatment groups. Evaluation of vitamin supplementation was observed on individual time points from d 0, 14, 28, 56, and 77 from the sheep. Parameters collected include body condition score (BCS), FAMACHA score, packed cell volume (PCV), and fecal egg count (FEC). There was no effect (P > 0.05) on BCS in either lamb or mature groups on any of the days within the trial. However, on d 56, there was a tendency for the FAMACHA score to be improved in the vitamin E lambs compared with the control lambs. Additionally, on d 56 for the mature group, there was a significant difference (P ≤ 0.05) that was observed within the Vit E+C group being less than the Dewormer and vitamin C groups. Treatments did not affect (P > 0.05) packed cell volume (PCV) throughout the trial in either lamb or mature ewes. On d 14 of the trial, lambs receiving vitamin E and C, or the anthelmintic treatment had decreased (P ≤ 0.05) strongyle FEC compared with the control lambs. The preliminary data analyzed suggests that vitamin E and/or C may work similarly to pharmaceutical anthelmintics in hair sheep to combat GIN. However, more research is essential to confirm the viability that vitamins may work as a sustainable alternative.
PSIII-8 CRISPR editing of IGF2 and MSTN to enhance productivity
Authors: Finchum Rebecca H , Dilger Anna C , Beever Jonathan E
Published: September 2024

The ability to modify the genomes of livestock species has previously been limited by low efficiency and the high cost associated with reagents and the generation of edited live animals (e.g., via somatic cell nuclear transfer). However, the CRISPR/Cas9 system has shown promise by improving specificity and efficacy, while decreasing costs associated with reagent acquisition and potentially live animal production (e.g., via direct editing of embryos). Given these potential improvements there are still a limited number of well-characterized genes for targeting. Nonetheless, there are two genes where molecular variation in different species has shown highly significant effects on increased lean growth and reduced adiposity, insulin-like growth factor 2 (IGF2) and myostatin (MSTN). In pigs, a G-to-A substitution in intron 3 of IGF2 (g.3072G >A) disrupts a conserved binding site for the transcriptional repressor ZBED6 allowing for increased postnatal IGF2 expression. This increased expression is associated with increased lean muscle yield and intramuscular fat deposition, while decreasing backfat. In livestock species other than the pig, numerous loss-of-function mutations in MSTN have been reported. MSTN is a known early regulator of myoblast differentiation, negatively regulating myoblast fusion into myotubes. This results in muscle hyperplasia causing the commonly referred to “double-muscling” phenotype. Animals of this phenotype have significantly increased skeletal muscle mass, improved feed conversion, and decreased fat deposition. These mutations have the potential to act synergistically as demonstrated by generation of a mouse line possessing both IGF2 overexpression and MSTN loss-of-function mutations. Within this line, wild-type (WT) mice have an average body weight (BW) of 19.64 ± 1.89 g at 11 wk of age. In comparison, IGF2 overexpression, MSTN loss-of-function, and the combination of both mutations have average BW of 23.54 ± 2.31 g, 26.14 ± 2.35 g, and 31.43 ± 2.39 g, respectively (P < 0.0001). Based on these results in mice we have initiated editing of both genes in cattle. Two male fetal fibroblast cell lines were generated from d 75 fetuses from high genetic merit Angus matings. Four CRISPR guide RNAs have been designed for both genes and assayed for their in vitro cleavage efficiencies. All guide RNAs exceeded 60% cleavage efficiency. CRISPR/Cas9 ribonuclear protein complexes were electroporated into each cell line. Targeted modifications will be confirmed through sequencing, and successfully modified cell lines will undergo somatic cell nuclear transfer to produce live animals.
PSV-14 The effects of calcium cyanamide on greenhouse gases, ammonia emissions, and the microbiome of dairy cattle lagoon water
Authors: Rocha Alice , Morales Briana , Mashad Hamed El , Pan Yuee , Zhao Yongjing , Mitloehner Frank M
Published: September 2024

Dairy manure management is responsible for a significant amount of greenhouse gas emissions (GHG) in California. Aside from redesigning infrastructure to adopt alternative manure management systems, there are few options available to farmers to mitigate emissions without substantial financial investment. Calcium cyanamide, a new manure additive, showed significant reductions in GHG emissions when applied to fresh dairy cow slurry, but has not been tested on dairy lagoon water. The aim of the present study was to investigate the effects of calcium cyanamide on GHG and NH3 emissions and the microbiome of dairy lagoon water. Lagoon water was collected from a commercial dairy, and distributed into 12 stainless steel barrels. Three treatments (n = 4/treatment) of different doses of calcium cyanamide were tested: high (LW-HD; 1 kg/m3 lagoon water), low (LW-LD; 0.5 kg/m3 lagoon water), and control with no calcium cyanamide (LW-CONT; n = 4). Each barrel was sampled over two, 14-d periods, staggered to four barrels at a time, using OdoFlux chambers to monitor emissions for carbon dioxide (CO2,), methane (CH4), nitrous oxide (N2O), and ammonia (NH3). Treatments LW-LD and LW-HD contained significantly more total solids, total nitrogen and total carbon compared with LW-CONT. There was also a significantly greater concentration of acetic acid in LW-LD and LW-HD treatments compared with LW-CONT. CO2 emissions in LW-LD and LW-HD were 2.96% and 12.03% less than LW-CONT. CH4 emissions in LW-LD and LW-HD were 80.9% and 85.13% less compared with LW-CONT. N2O emissions in LW-LD and LW-HD were 81.1% and 82.66% less than LW-CONT. However, NH3 fluxes were greater in LW-LD and LW-HD compared with LW-CONT by 65.26% and 65.73%, respectively. The microbiome of the lagoon water was also affected, with reductions in relative abundance of the Proteobacteria phylum responsible for nitrification in LW-LD and LW-HD and increases in the Firmicutes phylum containing acetogenic bacteria. Calcium cyanamide could inhibit methanogenesis by increasing acetogenic bacteria that compete with methanogens for fermentation substrates. Further research is needed to investigate the efficacy of calcium cyanamide in a commercial lagoon setting.
PSV-5 Characterizing the activity of bovine Lactobacillus strains against the top 7 Shiga-toxin Producing Escherichia coli strains
Authors: Ding Yiran , Niu dongyan , McAllister Tim A , Guan Leluo , Cobo Eduardo
Published: September 2024

Shiga toxigenic Escherichia coli (STEC), specifically serogroups O26, O45, O111, O103, O121, O145, and O157 (Top 7), pose significant health risks. Cattle are the primary reservoir of STEC, and effective intervention remains elusive. The identification of Lactobacillus spp. with antimicrobial activity as direct-fed microbials (DFMs) presents a potential strategy for pathogen reduction. These strains are not only capable of favorably modulating the gut microbiota but also possess the innate ability to produce bacteriocins that can target specific pathogens including STEC. Selection of viable anti-STEC Lactobacillus strains requires assessment of the presence or absence of prophage that may revert from the lysogenic to lytic phase and affect their efficacy. This study aimed to characterize anti-STEC potential of 14 Lactobacillus strains isolated from cattle and to identify their associated bacteriocins and prophages. Antimicrobial activity of 14 Lactobacillus strains against the top 7 STEC strains was determined using live culture spot assays and cell-free supernatants (CFS) well-diffusion assays. To further assess their anti-STEC efficacy, Lactobacillus strains with the strongest activity were selected and further evaluated in MRS broth culture and rumen fluid. The ability of Lactobacillus strains to inhibit STEC attachment to Caco-2 epithelial cells was also assessed. Prokka 1.14.6, and Bagel5 were utilized to identify genes encoding bacteriocins. Additionally, PHASTEST 3.0 was utilized to identify prophages. All 14 strains demonstrated antimicrobial activity against the top 7 STEC serogroups. Notably, L. agilis strains L3 and L6, with genome sizes of 2,063,576 bp and 2,071,091 bp respectively, and L. amylovorus L7 (883,016 bp) exhibited the greatest anti-STEC activities, targeting O157, O26, O45, and O103 for L3 and L6, and O157, O45, and O103 for L7. The CFS from these strains showed anti-STEC activity at pH 4.4-4.6, but not at 7, suggesting that organic acids played a role in inhibition. In MRS, DFM reduced STEC O157:H7 by 5 to 7.4 logs after 24 h. However, in rumen fluid, no notable reduction in STEC O157:H7 was observed. Bioinformatic analysis revealed that the L7 genome encoded Helveticin-J, a Class III bacteriocin. Prophage identified included 1 intact (51,818 bp) and 1 non-intact (17,267 bp) in L3, and 2 intact (46,916 bp, 20,295 bp) and 1 non-intact (13,939 bp) in L6, while no prophage was identified in L7. This study identified novel DFMs with activity against STEC, but future studies with cattle are required to confirm their ability to inhibit STEC.
PSV-4 Clodronate re-release in response to controlled exercise and bone stressors in juvenile horses
Authors: Conrad Matthew B , Leatherwood Jessica L , Glass Kati G , Arnold Carolyn E , Paris Brittany L , George James M , Martinez Rafael E , Mays Travis P , Bradbery Amanda N
Published: September 2024

Concerns over the extra-label use of bisphosphonates in skeletally immature horses has extended to include its likely re-release from bone into circulation in response to stressors. Therefore, the objective of this study was to be first to quantify the re-release of clodronate in response to controlled stressors. Yearling Quarter horses (n = 32) were stratified by age, body weight (BW), sex, and initial bone optical density into four treatment groups for a 168-d trial. Treatments consisted of control (CON; n = 8), single-dose (1X; d 84; n = 8), 2-dose (2X; d 0 and 84; n = 8), and four-dose groups (4X; d 0, 42, 84, and 126; n = 8). All horses received iso-volumetric intramuscular injections of either 1.8 mg/kg BW clodronate disodium (OSPHOSÒ) or saline (placebo) on d 0, 42, 84, and 126. Horses were housed in individual stalls (3.6 m × 7.2 m). Diets were formulated to meet nutrient requirements including concentrate offered every 12-h and ad libitum coastal bermudagrass (Cynodon dactylon) hay and water. Horses were exercised 5 d/wk with a progressive workload, and maximum exercise intensity was reached on d 120, verified via heart rate and blood lactate. On d 120, blood samples were collected prior to the start of the exercise bout (pre), and 0-, 0.5-, 1-, 3-, 12-, and 24-h post exercise. Both tuber coxae of each horse were biopsied on d 168 with blood samples collected prior to (pre), and 0, 12, 24, 48, 72, 168, and 336 h post biopsy. Clodronate was quantified in plasma from exercise and biopsy samples using liquid chromatography tandem mass spectrometry. Exercise and biopsy serum were analyzed for cortisol, a marker of stress, while biopsy serum was analyzed for substance P, a pain marker. Data were analyzed using SAS PROC MIXED. Exercise did not result in clodronate re-release as there was no treatment x time interaction or time effect (P ≥ 0.44), but clodronate was dose-dependently greater in treated groups throughout the exercise collection period (P < 0.01). A treatment x time interaction (P ≤ 0.01) was observed for clodronate concentrations surrounding bone biopsy in which concentrations decreased at 168 h post biopsy before increasing at 336 h in 4X horses. Substance P increased over time (P < 0.01) following biopsy, regardless of treatment. Despite decreasing over time (P ≤ 0.01), there were similarly no treatment differences (P ≥ 0.46) nor treatment ´ time interactions (P ≥ 0.78) for cortisol following either exercise or bone insult. In conclusion, submaximal exercise did not result in re-release of clodronate; however, direct bone insult disrupted clodronate concentrations in horses receiving 4 administrations of bisphosphonate despite no treatment impact on stress or pain indicators.
PSV-16 Evaluation of upper respiratory and fecal microbiomes in neonatal beef calves
Authors: Sowers Consuelo A , Smithyman Mackenzie M , Chung Max , Scott Matthew , Valeris-Chacin Robert , Duff Glenn C , Richeson John T , Capik Sarah
Published: September 2024

There is a critical lack of information on the timing of colonization of bovine respiratory disease-related bacteria in the upper respiratory tract, potentially affecting calf health and disease onset. The objective of this study was to evaluate the upper respiratory tract and fecal microbiomes of neonatal beef calves during the first 24 h of life compared with their dams at the time of birth. Late-gestation commercial beef cows (n = 28) were assigned to individual, soil-surfaced pens (6.25 x 2.29 m) fitted with canvas tarps on shared fences to limit contact between unrelated pairs. Left nasal (LN), right nasal (RN), fecal, and vaginal swab samples were collected from cows at a single time point promptly after parturition. Swabs of the LN, RN, and rectum were collected from calves at birth (0 h), 6, 12, and 24 h post-parturition. Samples were flash-frozen and stored at -80°C until processing. DNA was extracted from swabs using Power Soil Pro kit. Extracted DNA was used to prepare DNA libraries for full-length 16S rRNA gene sequencing on a MinION Mk1C device. Sequenced reads were classified using Centrifuge and used in microbiome analyses conducted in R to estimate the changes in the microbiome according to animal type (cow versus calf), time of collection, and sample type (nasal, fecal, or vaginal). Upper respiratory microbiomes significantly differed (P < 0.005) between cows and their offspring at birth. In nasal microbiomes, animal type explained 12.6% (P = 0.002) and 18.5% (P = 0.001) of variance in beta diversity in left and right cavities, respectively. Animal type explained 42.1% of the beta diversity variance in fecal microbiomes (P = 0.001). Nasal microbiomes at birth were significantly more dispersed in dams compared with their calves in both the LN (P = 0.03) and RN (P = 0.03). Similarly, fecal microbiomes of dams were significantly more dispersed (P < 0.0001) than those of their offspring. There was a clear transition of the microbial communities associated with calf age in the upper respiratory and fecal niches. Calf age accounted for 2% (P = 0.02), 3.5% (P = 0.001), and 28% (P = 0.001) of the variance in the beta diversity of the LN, RN, and fecal microbiomes, respectively. After adjusting for calf age, the laterality of nasal microbiomes was not significantly (P = 0.682) associated with the composition of microbial communities. In conclusion, calf microbial communities were dissimilar to that of their dam at birth. Additionally, microbial community transition was evident with each subsequent sampling time point, potentially influenced by the presence of the dam.
PSVI-13 Yield and quality of conventional and reduced lignin alfalfa harvested at different maturity stages in the Southeast United States
Authors: Pena Manuel , Velasquez Cesar , Hawes Kailin , Aguerre Matias J
Published: September 2024

The objective of this study was to evaluate the effect of conventional and reduced lignin alfalfa on forage dry matter (DM) yield and quality when harvested at different maturity stages. The study was conducted in field plots (1.5 m x 6.1 m) as randomized complete block designs with a split-plot arrangement of treatments. Two conventional (Ameristand 455TQ, TQR; Alfagraze 600, ALFA) and one reduced lignin (Ameristand 480 HarvXtra, HVX) alfalfa varieties were harvested at 28 (Early), 35 (Mid), and 42 (Late) d intervals in three consecutive years. Samples were analyzed for NDF, ADF, and ADL (as % DM). Average DM yield was greater for TQR than ALFA and HVX (8,335 vs. 7,119 kg/ha, P < 0.01). The DM yield of alfalfa harvested at Mid stage was significantly greater (8,888 kg/ha) compared with alfalfa harvested at Early (6,961 kg/ha) or Late stage of maturity (6,726 kg/ha). The reduced lignin alfalfa had reduced NDF and ADF concentrations than TQR and ALFA (36.1 vs. 37.4 and 29.4 vs. 30.9%, respectively). The two conventional varieties did not differ in NDF and ADF content. The HVX alfalfa tended (P = 0.06) to have reduced ADL concentration than TQR and ALFA (9.97 vs. 10.62%). Compared with Early alfalfa, forage NDF, ADF, and ADL concentration were greater (P < 0.01) in Late harvested alfalfa (35.3 vs. 39.3%, 28.7 vs. 32.1%, and 10.0 vs. 10.8%, respectively). Under the conditions of this study, results suggest that the evaluated reduced lignin alfalfa has a greater forage quality than the conventional varieties but at the expense of decreased DM yield.
PSIV-10 Thyroid hormone does not protect skeletal muscle mitochondrial function from heat stress in pigs
Authors: Wesolowski Lauren T , Kelly Jamianne J , Roths Melissa S , Rudolph Tori E , Semanchik Pier L , Rhoads Robert P , Baumgard Lance H , Selsby Joshua T , White-Springer Sarah H
Published: September 2024

Environmental heat stress (HS) can impair muscle mitochondrial function which may contribute to negative health outcomes, but little is known about potential treatments to rescue mitochondrial function during HS. To test the hypothesis that thyroid hormone (T3) would protect mitochondrial function during HS, samples were collected from the right ventricle (RV) of 3-mo-old, crossbred gilts under 4 different environmental conditions: thermoneutral (TN; 22°C; n = 8); 1 d HS (HS1; 38°C; n = 7); oral supplementation of 1.33 µgּ kg body weight (BW)-1ּ d-1 Cytomel (liothyronine sodium) during the 1 d HS (HS1TH; n = 8); and 7 d HS (HS7; n = 8). The oxidative portion of the semitendinosus (ST) was also collected from all groups plus a 5th group: oral supplementation of Cytomel during 7 d HS (HS7TH, n = 8). Mitochondrial volume density was estimated by citrate synthase (CS) activity, and oxidative phosphorylation (OP) and electron transfer (E) capacities were determined via high resolution respirometry. Data were analyzed using mixed linear models in SAS v9.4 with treatment group as a fixed effect and pig (treatment) as a random effect. Within the RV, the contribution of OP supported by complex I (PCI) to maximal E was less in HS1TH gilts compared with all other groups (P ≤ 0.02), and the contribution of E supported by complex II (ECII) to maximal E was greater in TN than HS1 or HS7 (P ≤ 0.02) and tended to be greater in TN compared with HS1TH gilts (P = 0.07). Within the ST, integrative (relative to tissue wet weight) PCI was greatest in TN gilts (vs. HS7 and HS7TH, P ≤ 0.0002; vs. HS1 and HS1TH, P ≤ 0.06) and least in HS7 and HS7TH (vs. HS1 and HS1TH, P ≤ 0.05). Integrative maximal P (PCI+II) was greatest in TN pigs (compared with HS1TH, HS7, and HS7TH, P ≤ 0.05; compared with HS1, P = 0.09). Integrative maximal E (ECI+II) was also greatest in TN gilts than all other groups (P ≤ 0.05) while ECII was greater in TN pigs compared with HS7 and HS7TH (P ≤ 0.009) and tended to be greater than HS1 and HS1TH (P ≤ 0.09). In ST, intrinsic (relative to CS activity) PCI and PCI+II were greater in TN compared with HS1, HS1TH, and HS7 pigs (P ≤ 0.03) and PCI+II tended to be greater in TN than HS7TH (P ≤ 0.06). Intrinsic ECI+II and ECII were greater in TN compared with all other treatment groups (P ≤ 0.04). These results suggest that T3 supplementation did not protect mitochondrial function from negative impacts of HS in skeletal muscle but may have modified electron transfer through complex I in cardiac muscle which may have implications on oxidative stress.
PSIV-6 Blood biomarkers of oxidative stress in offspring from dams infected with bovine viral diarrhea virus during late-term gestation
Authors: Chek Erlene , Loh Huey Yi , Van Campen Hana , Kincade Jess N , Hansen Thomas R , Engle Terry E
Published: September 2024

The objective of this experiment was to examine the impact of dams infected with bovine viral diarrhea virus (BVDV) during late gestation on inflammatory blood biomarkers in their offspring. Fetal infection with 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). It was hypothesized that offspring of dams transiently infected with BVDV on d 175 of gestation would have greater inflammatory blood biomarkers than control offspring. Unvaccinated, yearling Hereford heifers (n = 24), seronegative for antibodies to BVDV1 and BVDV2 were bred by artificial insemination with X chromosome-bearing sperm from an Angus sire. On d 175 of pregnancy, heifers were intranasally inoculated with either Dulbecco’s Modified Eagle Medium + 2% horse serum (sham control) or 4.0 log TCID50 noncytopathic type 2 BVDV to generate control and transient infected calves, respectively. All BVDV-inoculated dams seroconverted by d 14 post-inoculation and all sham-inoculated control dams remained seronegative. Twelve, seronegative control heifer calves were born to the control dams, and 11 seropositive (to type 2 BVDV) TI heifer calves were born to BVDV-inoculated dams. 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 body weight (BW) of 600 kg. Upon arrival, all animals received a standard heifer growth implant containing 200 mg of testosterone propionate and 20 mg of estradiol benzoate, a modified live viral vaccine containing IBR-BRSV-PI3, and were dewormed. Jugular blood samples were obtained every 28 d until harvest (280 d on feed) and analyzed for biomarkers of inflammation. Data were analyzed as a randomized block design with the MIXED procedures of SAS. There was a treatment x time interaction (P < 0.05) for plasma ceruloplasmin and the oxidized form of glutathione. On d 0 and 28 of the feeding period, all biomarkers were similar across treatments. By d 56 of the feeding period, ceruloplasmin (P < 0.03) and the oxidized form of glutathione (P < 0.01), indicators of chronic inflammation, were increased in plasma samples from TI heifers compared with controls. These parameters remained greater in TI heifers compared with controls throughout the feeding period. There were no treatment or treatment x time interactions for plasma interferon (INF)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-6, and haptoglobin. These data suggest that TI heifers may be experiencing a greater level of oxidative stress later in the finishing period. This research was supported by USDA-NIFA Grant #2019-67015-29866.
PSIV-12 Effects of creep-feeding supplementation on growth performance during the rearing and finishing phases of grazing Nellore young bulls
Authors: Sousa Luciana Melo , de Porcionato Marco Felício , Garcia Anna Lidia Francino Francino , Rigon Fernanda , Inácio de Abreu Mateus José Inácio José , de de Resende Flávio Dutra Dutra , Siqueira Gustavo Rezende Rezende
Published: September 2024

The study aimed to evaluate the effect of creep-feeding on growth performance of beef young bulls (n = 40) when they were subjected to an intensive rearing and finishing system. The experiment lasted 325 d, from May/2022 to April/2023, the calves were born in September/2021 and creep-feeding supplementation lasted 170 d, from December/2021 to May/2022. The experimental design used was a randomized block [blocked by body weight (BW) of calves in the beginning of supplementation]. The experimental units were the paddocks (4 paddocks per treatment, and 5 animals per paddock). The treatments consisted of supplementation on creep-feeding system or not during the nursing phase: control (mineral supplement ad libitum) and creep-feeding treatment (energetic protein supplement, 5 g/kg BWּ animal-1ּ d-1). After weaning, all the bulls were managed similarly with an energetic protein supplement (10 g/ kg BWּ animal-1ּ d-1) during the grazing intensive rearing phase, and 15 gּ/kg BWּ animal-1ּ d-1during the grazing intensive finishing phase) until slaughter. The bulls were allocated to grazing area of Urochloa brizantha cv. Marandu. The data were analyzed using the MIXED procedures of SAS (SAS Institute Inc., Cary, NC, USA, version 9.4). The bulls subjected to creep-feeding system had greater BW at beginning of rearing phase (+14 kg) and beginning of rainy season (+18 kg; P = 0.03; Figure 1). At beginning of finishing phase and slaughter, the bulls had the same BW (P ≥ 0.71; Table 1). The back and rump fat thickness measures showed tendency to be different between the treatments (P ≤ 0.10), where creep-fed animals were greater. Probably, creep-fed bulls slowed down their BW gain during the rainy season on rearing and finishing phases, due to presenting a change in the gain composition. Creep-feeding may have influenced the puberty of these bulls, and caused them to begin deposition of fat earlier than those that did not receive creep-feeding. Thus, the animal tends to balance BW with changes in the gain composition, and the percentage of muscle tissue tends to reduce, while the proportion of fat tends to increase. Creep-feeding supplementation increased the animals weaning weight by 14 kg but, it was not able to influence the slaughter weight due to changes in the gain composition.
PSIV-14 Short-term heat stress affects the plasma metabolome of Florida Cracker sheep
Authors: Harrison Makenzie , Mills-Widemon Anijia , Ikuejamoye-Omotore Sola , Reyes Zaira M Estrada , Ogunade Ibukun M , Cervantes Andres Pech , Terrill Thomas H
Published: September 2024

Florida Cracker sheep is a heritage sheep breed and an endangered species that was developed under natural selection in Florida, US. The objective of this study was to evaluate the effect of short-term heat stress on the plasma metabolome of Florida Cracker ewes (2 yr). A total of fourteen ewes were allocated to heat stress (HT, n = 7) or cooling (CTL, n = 7) conditions for 6 wk during the summer season. Treatment groups were grouped in covered concrete floor pens with similar dimensions and characteristics and had access to shelter, feed, and freshwater ad libitum. The HT pen was exposed to regular ambient temperatures, and for the cooling pen, an evaporative cooling fan was used. Data for ambient temperature and relative humidity of HT and CTL pens were recorded every week to estimate the temperature humidity index (THI). Blood samples were collected from each experimental ewe 1 wk before the start of the experiment (baseline) and at wk 1, 2, 3, 4, 5, and 6 post-treatment. Plasma was extracted from the blood and processed for targeted metabolomics. Targeted metabolomics was performed using Nuclear Magnetic Resonance spectroscopy to quantify a total of 50 metabolites, including organic acids, amino acids, hexoses, lipids, and carnitines. Statistical analysis for biomarker and pathway enrichment was performed using Metaboanalyst 5.0. The THI values for the HT and THI groups ranged from 81.3 to 89.5 and from 73.5 to 75.6, respectively. A total of 19 differentially abundant metabolites were identified between HT and CTL. The pathway enrichment analysis showed upregulation of fatty acid and primary bile biosynthesis, and glutathione, porphyrin, glycine, serine, and threonine metabolism (P ≤ 0.05) in HT compared with CTL sheep. These metabolic pathways could have a role in the response of the ewes to short-term HT. Our findings highlight that short-term HT alters the plasma metabolome of Florida Cracker ewes. Understanding these changes can contribute to the development of effective management strategies to mitigate the detrimental impact of HT on sheep operations in the Southern US.
PSV-20 Supplementation of an electrolyte solution improves water intake in receiving beef cattle under commercial feedlot conditions
Authors: Seymour Dave J , de Carvalho Isabela P C , Martín-Tereso Javier
Published: September 2024

During transport to and receiving at feedlots, cattle are exposed to a variety of stressors, including changes in social structure due to separation and mixing of groups, handling, and a lack of access to feed and water for extended periods of time. These stressors often result in loss of body mass and dehydration, which if not adequately addressed upon feedlot arrival, may result in increased morbidity and mortality. The objectives of this experiment were to evaluate changes in body weight (BW) and water intake in cattle supplemented with an electrolyte solution upon feedlot arrival. Shipments of animals were weighed upon arrival at a commercial feedlot operation and moved to a set of holding pens where animals remained for a 3-d receiving period prior to entry into the feedlot. Sets of holding pens (n = 5 sets of 4 pens per treatment) were blocked by arrival date and randomly assigned to receive either a negative control (water) or an electrolyte solution during the receiving period. Daily free-choice fluid intake was monitored per pen, and animals were weighed at the end of the receiving period. Average fluid intake per animal was increased by 46.9 % (10.3 L/d; P = 0.013) in response to the addition of electrolyte. No differences due to treatment were observed in average origin BW, arrival BW, or BW recovery. This suggests that while recovery of BW was not affected, supplementing receiving cattle with an electrolyte solution may be an effective method of improving hydration status prior to feedlot entry. Future work aims to evaluate potential changes in morbidity and mortality during the finishing period following a similar supplementation strategy.
PSIX-7 A multi-strain probiotic modifies fecal microbial populations of healthy adult dogs
Authors: Zubillaga Marcial A Guevara , Jørgensen Jens Noesgaard , Jørgensen Lisbeth , Alaverdova Lidiia
Published: September 2024

Probiotics can modulate the intestinal microbiota and benefit the health of the host, whereas environmental stressors can negatively impact the composition of the intestinal microbiota. Lactic acid bacteria (LAB), most commonly Lactobacillus and Bifidobacterium species, are well-known organisms with probiotic potential. The objective of this study was to determine the impact on the fecal microbial population of healthy dogs, after ingestion of a probiotic blend of Lactobacillus acidophilus-286, Bifidobacterium animalis subs. Lactis-689, and Enterococcus faecium-202. Adult dogs [n = 30; 15 male, 15 female; mean body weight (BW) = 14.7 kg; mean age = 3.3 yr) were enrolled in this placebo-controlled and blinded study. After a 7-d washout period, dogs were allocated into two groups similar in terms of breed, BW, age, and sex. Dogs were fed a complete dry extruded diet and at time 0 h on d 0 received orally 4 g of a placebo paste or probiotic paste corresponding to the target dose of 4x107 total CFU. Administration of the placebo or probiotic was repeated 12 h and 24 h after the first dose. Afterward, fecal scores were evaluated daily for 7 d. Fresh fecal samples were collected on d 0, 3, and 7 for microbial enumerations and fecal metabolite measurements. Fecal microbial count data did not conform to the assumptions of normality and homogeneity of variances, consequently, non-parametric tests were performed for comparisons. Fecal scores, dry matter, and metabolites were not different between groups. Fecal counts of Lactobacillus spp., Bifidobacterium spp., and Enterococcus spp. were greater on both d 3 and d 7 (P < 0.01) in dogs that consumed probiotics. Fecal counts of both Escherichia coli and Clostridium perfringens were fewer (P < 0.01) in dogs that consumed probiotics. In conclusion, the consumption by dogs on d 0 of a probiotic blend of Lactobacillus acidophilus-286, Bifidobacterium animalis subs. Lactis-689, and Enterococcus faecium-202 modified the intestinal microbiota up to 7 d after consumption, as evidenced by the increase of lactic acid bacteria and the decrease of Escherichia coli and Clostridium perfringens in feces.
PSXII-1 Comparative analysis of the training response of Raramuri Criollo and Angus Cattle to virtual fencing
Authors: Perea Andres Ricardo , Macon Lara , Dunlap Robby , Funk Micah , Winkler Parker , Campa-Madrid Sara E , Spetter Maximiliano J , Filbert Meghan , Cibils Andres , Estell Rick E , Duff Glenn C , VanLeeuwen Dawn , Utsumi Santiago A
Published: September 2024

Virtual fencing (VF) collars rely on GPS tracking and audio warning-electric cueing to exclude or contain livestock inside geofencing zones. Behavioral differences between breeds may occur that explain differences in adaptation to VF. Training response of nonlactating Raramuri Criollo (RC) and Angus-Herford (AH) cattle to a commercial VF system was compared at the Jornada Experimental Range (USDA-ARS) in Las Cruces, NM during November and December, 2023. Thirty RC and 30 AH cows naive to VF were instrumented with Nofence collars (Molde, Norway) and randomly allocated by breed to rectangular pens (n = 6) of similar size (0.16 ha). Cows were fed wheat hay ad libitum in feeding stations at the east and west ends. Unrestricted water, mineral supplements and shade were provided at the center of pens. Two VF exclusion areas of similar size (280 m2) were set in the east and west ends, establishing eventual VF restricted zones (RZ). The training was divided into six 3-d periods. In period 1, RZ were deactivated, allowing cows to adapt to feed, peers, operators and pens. In period 2, RZ were activated on the west end of each pen, with the east side serving as VF containment zone (CZ). In period 3, RZ were switched to the east side, with the west side serving as the CZ. Both RZ were deactivated in period 4 to serve as an extinction phase. The RZ configuration in periods 2 and 3 were repeated in periods 5 and 6, serving as testing phase. Audio warnings (AW), electric pulses (EP), and the ratio (RT) of EP to AW were analyzed with a repeated measures model to evaluate fixed effects of breed, period, day(period), and all interactions according to a completely randomized design with day(period) as repeated factor. Significant effects were tested using LSD (P < 0.05). Both AW and EP were affected by the triple interaction, indicating greater AW and EP in d 1 of period 2 for AH than RC cows. Likewise, AW were greater for AH in period 2, and EP were greater for AH cows in periods 2 and 3 and for RC cows only in period 2. Among day(period), AW and EP were greater for both breeds in d 1 of period 2, and in d 1 of period 3 for AH. No interaction in RT was detected, but mean values were greater for AH than RC, in periods 2 and 3 than 5 and 6, and in d 1 than d 2 and both than d 3, as anticipated. The RT declined through time suggesting that both breeds learned to respond safely to changing VF configurations, but consistent behavioral differences may explain a different VF risk assessment and vigilance of RC cows compared with AH cows.
PSXII-8 Environmental cost effects of different manure treatment methods on dairy farms
Authors: Wang Han , Ma Lu , Bu Dengpan
Published: September 2024

The issue of manure disposal in dairy farms has long been a significant challenge afflicting the dairy farming industry, as manure poses various detrimental effects such as greenhouse gas emissions and land pollution. This remains an urgent concern for the industry to address. The traditional tank fermentation oxidation pond form of manure treatment and the new biogas power generation mode of manure treatment are currently widely employed in dairy farming enterprises. The evaluation and analysis of the environmental cost of new treatment modes should be conducted using scientific methods to determine which approach is more environmentally friendly. We selected two dairy farms with roughly the same number of dairy cows and the same management level, and the feed formula of the two dairy farms was basically consistent with the herd structure. Among them, the traditional tank fermentation manure treatment pasture, and the biogas power generation pasture. The Life Cycle Assessment (LCA) method of SimaPro software was used, and the software version was 9.0.0.48. In the life cycle assessment, we take into account the depletion of fossil energy, cement, metals, chemical products, electricity, heat, and mechanical pumps during the process of manure treatment. After accounting, the following conclusions are developed. During the whole life cycle of dairy farming, greenhouse gas emissions mainly fall into three types: methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O). CH4 accounts for 64% of the total emissions, which is mainly produced in the process of animal feeding, and a small part comes from manure treatment. CO2 accounts for 34% of the total emissions from the production of feed raw materials. The smallest proportion of transport and fossil energy consumption is N2O, which is mainly produced by manure treatment processes and accounts for 2% of total emissions. The environmental cost of the traditional tank fermentation oxidation pond is 17.6% greater than that of the new type of biogas power generation.