Journal of Animal Science

Bond, Judith J; Hudson, Nicholas J; Kamath, Karthik S; Wheeler, David; Woodgate, Serey; Oddy, Victor H

doi: 10.1093/jas/skaf027pmid: 39907549

Thirty-six Merino wethers (10-mo-old) were fed ad libitum for 30 d 2 diets;1) low metabolizable energy diet (LME; 30% lucerne: 70% cereal chaff) and 2) high ME diet (HME; 40% rolled barley grain: 50% lucerne: 10% cereal chaff). Effects of diet on dry matter intake (DMI), ME intake (MEI), liveweight (LWT), average daily gain (ADG), carcass lean or fat gain, liver and empty rumen weight, and plasma metabolites were analyzed. A membrane-enriched protein fraction of rumen epithelium (RE) isolated enzymatically from whole depth rumen wall was quantified for each sheep using tandem mass tag mass spectrometry (TMT-MS). The presence or absence of acetylation of lysine residues on identified proteins was counted and the position of the lysine acetylation was recorded. In lambs fed the HME diet, DMI (P < 0.001), MEI (P < 0.001), ADG (P < 0.001), fat (P < 0.001), and lean gain (P < 0.001), as well as liver (P < 0.001) and empty rumen (P < 0.009) weight were greater than those fed the LME diet. Plasma glucose (P < 0.001) and βhydroxybutyrate (P < 0.001) at 3 and 5 h after feeding was greater in HME diet than in the LME-fed lambs. Changes in RE protein abundance in the LME versus HME-fed lambs were associated with metabolism in the peroxisome, protein processing in the endoplasmic reticulum (ER), valine, leucine and isoleucine degradation, and carbon metabolism. Acetylation of lysine was detected in enzymes involved in glycolysis, tricarboxylic acid (TCA) cycle, and fatty acid (FA) metabolism. Quantitative differences in the abundance of RE proteins that carry out intracellular processes of energy expenditure were associated with the concentration of ME (MJ/ kg DM) in the diet of growing lambs. The detection of lysine acetylation sites suggests a difference in the ME of the diet regulates enzymatic activity in central metabolic pathways in the RE cells.

Genther-Schroeder, Olivia N; Smerchek, Dathan T; Penner, Gregory B; Hansen, Stephanie L

doi: 10.1093/jas/skaf052pmid: 39981644

Three experiments were conducted to characterize Zn appearance and disappearance in the rumen, rumen epithelial Zn importers and exporters, the directionality of Zn movement, and the effect of supplemental Zn on rumen epithelial structure. In experiments 1 and 2, ruminally fistulated steers (n = 4) weighing 736 ± 23.3 kg were used in a crossover experiment with 2 dietary Zn concentrations (ZINC; 0 [CON] or 120 mg supplemental Zn/kg DM [Zn120], from ZnSO4) in a 45% forage, 55% concentrate diet (experiment 1) or a 92.5% concentrate and 7.5% forage diet (experiment 2) to assess Zn appearance and disappearance in the rumen using the washed reticulo-rumen technique (WRR). Experiment 3 used 20 individually housed Hampshire crossbred wether lambs (35.1 ± 4.57 kg) fed for 60-d to evaluate the impact of dietary grain and Zn concentrations on ruminal epithelium Zn concentration, Zn transporters, and proteins integral to epithelial integrity. This experiment was a 2 × 2 factorial, with 2 diet types (DIET; 45% forage and 55% concentrate [HF] or 7.5% forage and 92.5% concentrate [HG]), and 2 supplemental Zn treatments (ZINC; 0 mg [CON] or 120 mg [ZN] supplemental Zn/kg diet DM) from ZnSO4. In experiments 1 and 2, ZINC did not affect the rate of disappearance (k) or plateau (B) digestive model parameters for buffer Zn (P ≥ 0.34) but ruminal Zn disappearance was numerically greater in experiment 2. In experiment 3, there was a DIET × ZINC effect (P = 0.05) where HG + ZN had the greatest rumen epithelial Zn, and HF + ZN had the least. There was an interaction between DIET and ZINC on papillae length (P = 0.05), where papillae length was shorter in HF than HG, and within HG, ZN animals had shorter papillae than CON (P = 0.01). A DIET × ZINC effect was noted for ZnT1 RNAscope score (P = 0.01) within the stratum spinosum layer where HG + CON wethers had greater mean ZnT1 RNAscope score than other treatments (P ≤ 0.006). Ruminal Claudin-7 protein expression was lesser in HF (P = 0.01) and tended to be lesser in ZN (P = 0.09). Overall, these experiments highlight the dynamic nature of ruminal Zn metabolism and are supporting evidence for the relationship between ruminal health and dietary grain and Zn concentrations.

Engle, Bailey N; Thallman, Richard Mark; Snelling, Warren M; Wheeler, Tommy L; Shackelford, Steven D; King, David Andy; Kuehn, Larry A

doi: 10.1093/jas/skaf048pmid: 39985752

Heterosis, or hybrid vigor, is traditionally defined as the advantage of crossbred progeny relative to the average performance of their purebred parents. This advantage is due to increased heterozygosity in these crosses, which increases phenotypic expression in traits influenced by non-additive gene action. These heterosis effects may vary depending on the breed of animals in the original cross; however, breed-specific estimates are difficult to obtain because of a lack of contemporary comparisons among crossbred and purebred cattle. The Germplasm Evaluation Program at the U.S. Meat Animal Research Center was designed to evaluate 18 of the most highly utilized beef breeds in the United States and enable contemporary comparisons among purebreds and their crosses. Therefore, the primary objective of this study was to quantify the differences in breed-specific heterosis for growth and carcass traits in these 18 U.S. beef breeds. Specific traits analyzed were direct and maternal birth weight, direct and maternal 205d adjusted weaning weight, 365 d postweaning gain, marbling score, ribeye area, backfat thickness, and carcass weight. Specific heterosis effects were estimated using 2 different models: 1) a biological-group heterosis model where heterosis was estimated for crosses between British, Continental, and Brahman as breed groups, and 2) an average breed heterosis model where heterosis was estimated as the regression on average predicted breed heterozygosity arising from mating each of the 18 breeds to a randomly chosen animal in the population. Each model also included a random breed-specific cross-effect for each pair of breeds. Biological-group heterosis, or the expected deviations from a purebred mean between all crosses of British, Brahman, and Continental groups, was found for all traits (P < 0.0001), except marbling. The greatest increases in calf performance were estimated for crosses containing Brahman, especially for growth traits and maternal ability. Average breed-specific heterosis was also significant (P < 0.05) under the second model for all traits except marbling and maternal birth weight. Again, the greatest increase in calf performance across a majority of traits was found to be the result of crosses with Brahman. These estimates may be used by breeders to make more informed crossbreeding decisions and to tailor their choice of breeds to their specific production environment and breeding objectives.

Trauner, Alex M; McCoski, Sarah R; Satterfield, M Carey; Bradbery, Amanda N

doi: 10.1093/jas/skaf060pmid: 40036360

Reproductive health of male offspring following perturbations in maternal nutrition is not well-described in the horse; therefore, the objective of this study was to determine the effects of maternal overnutrition on neonatal foal testicular development. Sixteen Quarter Horse mares were used in a completely randomized design and stratified by expected foaling date, body weight, and body condition score into 1 of 2 dietary treatments beginning on gestational day 235: control (CON; n = 8) fed to meet nutrient requirements and overfed (HIGH; n = 8) fed 40% above CON. At 5 h postpartum, foals were euthanized, and testes from male foals were harvested, weighed, and stored for analyses. Samples were numerically coded in a blinded fashion and processed randomly to eliminate bias. Histomorphometric evaluations were performed following a hematoxylin & eosin stain and evaluated using ImageJ. All data were analyzed using the MIXED procedure in SAS v9.4. Horse within treatment served as a random effect, with a main effect of treatment. For RNA sequencing, differential gene expression analysis used DESeq2 1.20.0 R package to compare gene expression levels between CON and HIGH, and P-values were adjusted using the Benjamini–Hochberg correction. The threshold for significance was set at P ≤ 0.05 with trends toward significance at 0.05 < P ≤ 0.10, with sequencing data using adjusted P-values. Stringency was set to include differentially expressed genes with an unadjusted P-value < 0.05 for pathway enrichment analysis. Testes from HIGH foals (n = 4) were 61% heavier than testes from CON foals (n = 4; P < 0.01). There was no difference in individual seminiferous tubule area (P = 0.76) or Sertoli cell number within tubule (P = 0.57); however, testes from HIGH foals had 2.3 times fewer tubules per 10× magnification field than CON foals (P = 0.01). Further, tubules represented a lesser percentage of image area relative to interstitial tissue in testes from HIGH foals (P = 0.05). RNA sequencing revealed 56 differentially expressed genes between HIGH and CON testes (P-adjusted < 0.05). Differentially expressed genes represented biological processes related to steroidogenesis, cell regulation, and energy metabolism. Thus, late gestation maternal overnutrition alters fetal testicular development with potential long-term implications for reproductive function.

Cheng, Yi-Chi; Duarte, Marcos Elias; Kim, Sung Woo

doi: 10.1093/jas/skaf036pmid: 39935378

Removing filtration and crystallization provides amino acids with reduced purity because Corynebacterium glutamicum cell mass (CGCM) is not removed. This study aimed to evaluate the nutritional and functional values of granulated Threonine (Thr) and Valine (Val) with CGCM in diets for growth performance, jejunal mucosa-associated microbiota, nutrient digestibility, and health of nursery pigs. Seventy-two newly weaned pigs (28 d-of-age; initial body weight (BW) of 8.2 ± 0.4 kg) were allotted to 9 treatments (n = 8) based on a randomized complete block design with sex and initial BW as blocks. Treatments consisted of a basal diet with different levels of standardized ileal digestible (SID) Thr and Val: NC (SID Thr and SID Val at 70% of NRC requirement), CT (95% SID Thr using crystalline Thr); CV (95% SID Val using crystalline Val); PT (95% SID Thr using ThrPro); PV (95% SID Val using ValPro); HCT (5 × crystalline Thr used in CT); HCV (5 × crystalline Val used in CV); HPT (5 × ThrPro used in PT); HPV (5 × ValPro used in PV). Diets were fed to nursery pigs for 25 d in 2 phases (10 and 15 d, respectively). Feed intake and BW were recorded at the end of each phase. Blood samples were collected to measure serum proteins, metabolites, and electrolytes on day 21. Pigs were euthanized at day 25 to collect liver and jejunal tissues for morphological evaluation and jejunal mucosa to measure intestinal health biomarkers. Data were analyzed by SAS using MIXED procedure. Pigs with 95% SID Thr or 95% SID Val tended to have greater average daily gain (P = 0.078) and gross energy digestibility (P = 0.058), had greater (P < 0.05) jejunal villus height, and had lower (P < 0.05) plasma urea nitrogen and liver fibrosis than pigs with 70% SID Thr or 70% SID Val, respectively. Pigs fed a diet with HAAPro had increased (P < 0.05) alpha diversity of jejunal mucosa-associated microbiota than pigs fed a diet with AAPro. Pigs fed a diet with HAAPro had increased (P < 0.05) relative abundance of Bifidobacterium and decreased (P < 0.05) relative abundance of Comamonas than pigs fed a diet with AAPro. In conclusion, increasing the supplementation of AAPro by 5-folds than typical level did not negatively affect growth performance whereas beneficially modulated the jejunal mucosa-associated microbiota. Results suggest that AAPro can effectively replace the use of crystalline amino acids in pig diets while potentially reducing feed costs due to the reduced cost of producing such amino acids.

Dalto, Danyel Bueno; Audet, Isabelle; Roy, Caroline; Villeneuve, Geneviève; Matte, J Jacques; Lapointe, Jérôme

doi: 10.1093/jas/skaf024pmid: 39901732

This study compared the effects of different vitamin D supplementation strategies to pre- and postweaning piglets on vitamin D metabolism and health-related parameters. Sixty Yorkshire-Landrace × Duroc suckling piglets were selected at the first day of age and randomly assigned to one of two vitamin D supplementation strategies (n = 30 pigs per treatment): CTR—oral saline at days 2, 8, and 21 of age and, from weaning (day 21), in-feed supplementation with 2,000 IU of vitamin D as cholecalciferol; and VD—oral 25-hydroxycholecalciferol (25(OH)D3) solution at days 2, 8, and 21 of age plus 15-min exposure to UVB light every second day from day 14 until day 21 and, from weaning, in-feed supplementation with 2,000 IU of vitamin D as 25(OH)D3. Piglets were slaughtered (n = 10 pigs per treatment/day) at days 21 (before start in-feed experimental diets), and 28 and 35 and blood and tissues samples (jejunum, liver, and kidney) were collected. Body weight (BW), concentrations of serum 25(OH)D3 and jejunum, liver, and kidney mRNA expression of genes related to vitamin D, antioxidant system, and immune defense were measured. Body weight was not affected by treatments (P ≥ 0.34). Serum 25(OH)D3 concentrations were greater for VD piglets at day 21, 28, and 35 (P < 0.01). No effect of treatment was detected (P ≥ 0.14) for mRNA expression in the jejunum mucosa. In the liver of VD piglets, mRNA expressions of genes related to the antioxidant system were lower at day 21 (NDUFB2) and at day 28 (BNIP3, GPX4, and MSRA) (P ≤ 0.10). The mRNA analysis in kidney during the overall period detected higher expression of genes related to the mitochondria oxidative phosphorylation (COX17, NDUFB2, and NDUFB6) in VD groups compared with CTR (P ≤ 0.09). The expression of CYP27B1 in kidney was higher at day 28 and CYP24A1 was lower at day 21 but higher at day 35 for VD animals. In conclusion, during the preweaning period, dietary 25(OH)D3 supplementation combined with UVB exposure was effective in increasing serum 25(OH)D3 concentrations at weaning, whereas in the postweaning period, dietary 25(OH)D3 supplementation at 2,000 IU/kg was more efficient then dietary cholecalciferol at similar levels. The overall results indicate that 2,000 IU of vitamin D/kg of diet, independently of source, may be enough to improve the vitamin D status of postweaning piglets. However, the use of dietary 25(OH)D3 may promote a better modulation of vitamin D metabolism and redox balance.

Roskam, Emily; Kenny, David A; Kelly, Alan K; Hayes, Maria; Palevich, Nikola; Maclean, Paul H; O’Flaherty, Vincent; Biswas, Ambarish; Waters, Sinéad M

doi: 10.1093/jas/skaf032pmid: 39913259

Oils high in polyunsaturated fatty acids (PUFA) and seaweeds containing phlorotannins have potential anti-methanogenic effects in ruminants. This study assessed the potential of dietary supplementation with linseed oil, Ascophyllum nodosum or treated A. nodosum in an intensive beef cattle feeding system on animal performance, gaseous emissions, ruminal fermentation and microbiota, and muscle fatty acid profiles. Seventy-two dairy-beef bulls (380 kg; 11 mo of age) were randomly allocated to one of four dietary treatments (n = 18) for a 70-d period. The diet consisted of a 60:40 grass silage:concentrate ratio. Silage was offered daily (0900 hours) and concentrates were offered twice daily (0800 and 1500 hours). Dietary treatments were incorporated into the concentrate portion of the diet as follows; 1) CON (no supplementation), 2) LSO (linseed oil), 3) SW (A. nodosum), and 4) EX (A. nodosum extract), included to target 0%, 4%, 2%, and 2% of dry matter intake (DMI), respectively. The concentrates were formulated to be isonitrogenous across the 4 treatment groups. Total DMI (American Calan Inc., Northwood, NH), average daily gain (ADG), gain:feed, and enteric emissions (GreenFeed; C-Lock Inc., Rapid City, SD) were measured for the 70-d supplementation period. Total DMI (P = 0.17), ADG (P = 0.28), gain:feed (P = 0.68), and total tract digestibility (P = 0.70) did not differ across treatments. Daily methane production (P < 0.001) for CON, LSO, SW, and EX was 210, 170, 202, and 193 g/d, respectively, resulting in reductions of 19% and 8% for LSO and EX, respectively, relative to CON. Ruminal fermentation parameters show that LSO was the only dietary treatment to increase propionate (P = 0.09) and decrease butyrate (P = 0.04) concentrations relative to CON. Microbial analyses showed LSO supplementation increased and decreased relative abundances of fungal genera Buwchfawromyces and Piromyces, respectively, while altering relative abundances of the bacterial genera Muribaculaceae, Bacteroidales RF16 group and Bacterium F082. Additionally, LSO increased linolenic acid (P < 0.001) and n-3 PUFA (P < 0.001) concentration of the longissimus dorsi muscle compared to CON, SW, and EX. In conclusion, LSO was the most effective dietary supplementation strategy compared to CON, EX, and SW, whereby it reduced methane emissions, modified ruminal fermentation and microbial profiles, and enhanced beneficial muscle PUFA concentration, without impacting animal performance.

Ojeda-Marín, Candela; Cervantes, Isabel; Formoso-Rafferty, Nora; Gutiérrez, Juan Pablo; Rodríguez-Ramilo, Silvia Teresa

doi: 10.1093/jas/skaf023pmid: 39921654

Inbreeding depression (ID) is usually observed as reduced survival and fertility and may have a variable impact in different populations. The aim of this study was to estimate ID from genomic and pedigree data in the litter size (LS) of the high variability (H-Line) and the low variability (L-Line) mice lines divergently selected for environmental birth weight variability. Of these, the L-Line performed better on traits related to robustness. A total of 1587 females from 26 selection generations were genotyped with a high-density SNP array. LS data of 732 L-Line and 648 of H-Line animals were used. The following were calculated: pedigree inbreeding coefficient (FPED), genomic inbreeding derived from different genomic matrices (FNEJ, FL&H,FVR1, FVR2, and FYAN), from runs of homozygosity (FROH) and from homozygosity by descent probabilities (FHBD). FROH were calculated in the 19 autosomes (CHR). FROH and FHBD were divided into nine lengths and age classes, respectively. All the inbreeding coefficients were standardized by the mean inbreeding coefficient of the 1st generation. Regression coefficients (m) obtained from genomic data were between −3.71 with FVR2 and −5.09 with FHBD in the H-Line, and that estimated from FPED was −5.67. In the L-Line the m obtained from genomic data were between −3.52 with FVR2 and −4.55 with FHBD, and that obtained with FPED was −4.08. Significant ID effects were detected in CHR13 in the H-Line and CHR1 and CHR9 in the L-Line. The m negative trended to be lower as the ROH length increased. The age of the homozygosity by descent segment performed differently in each line, for example FHBD raised 128 generations ago produced a significant positive effect only in the L-Line. The effect of global inbreeding coefficients on the LS was negative in both lines with a higher impact in the H-Line than in the L-Line, suggesting the L-Line having higher robustness. CHR 1, 9, and 13 were candidates for future gene search. In general, more recent FROH and FHBD presented negative effects on LS while older FROH and FHBD presented positive effects on LS in both selected lines.

Schmid, Markus; Haas, Valentin P; Sarpong, Naomi; Rodehutscord, Markus; Seifert, Jana; Camarinha-Silva, Amélia; Bennewitz, Jörn

doi: 10.1093/jas/skaf028pmid: 39909847

Improving protein efficiency in pork production is a desired goal regarding resource conservation and climate protection, whereby animal breeding has great potential for sustainable improvements. Nitrogen utilization efficiency (NUE) is an important trait but laborious to measure. As blood urea nitrogen (BUN) can be used to predict NUE, it is often used as indicator trait. Both NUE and BUN were found to be heritable; however, microbial studies have not yet been carried out. The present study aimed to investigate the role of the gastrointestinal microbiota in the context of N efficiency in different fattening phases. The dataset consisted of 450 Landrace × Piétrain pigs fattened in a 2-phase feeding regime. All pigs were fecal sampled and phenotyped in 2 fattening phases, referred to as sampling period (SP) 1 and SP2, in week 13 and week 16 post natum, respectively. Microbial communities in feces were compared across SPs, and significant differences were observed. Mixed linear models were applied to quantify the microbial variance and microbiability for NUE, BUN, and related traits within each of the SPs. Except for NUE in SP1, all microbiabilities were significant and ranged from 0.079 to 0.471. Microbiome-wide association studies revealed a polymicrobial trait architecture characterized by the contribution of many genera, with each genus having a relatively small effect on the traits. In total, 4 and 11 microbial genera were significantly associated with NUE and BUN, respectively. Microbial correlations were estimated between traits within SPs via bivariate analyses. Blood urea nitrogen was significantly correlated with N intake and retention in SP1 but not in SP2. Fecal microbiota composition differed significantly between SPs and the use of microbiota data across SPs resulted in a remarkable drop in microbiability for nearly all traits. This implies that microbiota data should be representative of the time point of phenotyping to fully capture microbial contribution to trait expression. The results suggest that jointly using genomic and fecal microbial data might be expedient to improve protein efficiency in fattening pigs.

Pearce, Sarah C; Kerr, Brian J

doi: 10.1093/jas/skaf037pmid: 39921848

Aspirin (acetylsalicylic acid) is a nonsteroidal anti-inflammatory drug which has been a widely used analgesic for pain relief as well as an anti-inflammatory medication. However, it also causes negative effects on the gastrointestinal (GI) tract including GI bleeding, peptic ulcers, and can also impact the small intestine. Enhanced liquid aspirin (ELA) contains a combination of a salicylate compound, glycerin, triacetate, and saccharin which is more stable than aspirin alone and may reduce negative effects on the GI tract, while still exerting positive effects on inflammatory processes. The objective of this pilot study was to evaluate oral ELA in healthy weaning pigs. Eight pigs per treatment were gavaged daily for 5 d with either saline controls (CON) or 2 mg/kg body weight ELA. After the 5-d dosing period, pigs were weighed and then euthanized for intestinal sample collection. ELA-administered pigs gained significantly more body weight relative to initial body weights compared to CON pigs (8% vs. 13.7%; P < 0.05). Additionally, there was the tendency for an increase of 24% in villus height in ELA pigs compared to CON (P = 0.06) and significant increases in relative protein expression of Claudins (CLDN) 3 and 7 (P < 0.05). Finally, several genes were altered in ELA-fed pigs compared to CON including stem cell markers and immune markers. All in all, this data showed that ELA was well tolerated in a pig model, showed a preliminary improvement in body weight, and had no observable negative impacts.