Journal of animal science最新文献

{"title":"Impact of farrowing crate enrichment strategies on the welfare and performance of sows, suckling piglets, and post-weaned piglets.","authors":"Katherine E Klassen,Jessica A Pempek,Brian T Richert,Kristina M Horback,Kara R Stewart,Jeremy N Marchant,Marisa A Erasmus","doi":"10.1093/jas/skaf196","DOIUrl":"https://doi.org/10.1093/jas/skaf196","url":null,"abstract":"In conventional pig production, lactating sows are typically housed in farrowing crates that restrict movement and environmental engagement, raising welfare concerns. Farrowing pen also lacks behavioral stimulation for suckling piglets, hindering species-specific behaviors. Environmental enrichment may improve welfare by redirecting behaviors-such as chewing-away from conspecifics in piglets and pen fixtures in sows. However, few studies have explored its effects in farrowing crates, particularly regarding optimal placement within these spatial constraints. This study evaluated the impacts of enrichment strategies on welfare and performance of 37 lactating sows and their litters from birth through early post-weaning. Sows and litters were divided into three groups: both had access to enrichments (SPE), only piglets had access (PE), and control group with no enrichments (CON). Point-source objects (PorkyPlays and wooden blocks on rope) were placed 2 days after sows moved into farrowing crates until 2 weeks post-weaning. Sow salivary cortisol was collected at four timepoints and pressure sores were assessed at 8 timepoints from 24 hours after crate entry to weaning. Piglet tear stains and skin lesions were recorded throughout the lactation phase. Suckling piglet average daily gain (ADG) was analyzed at d 1-7, d 7-14, and d 14-weaning. In the nursery, salivary cortisol, tear stains, and skin lesions were measured on d 1, 7, and 14 post-weaning, with an additional cortisol sample at d 0 post-weaning. Nursery piglet ADG was analyzed from weaning to d 14 post-weaning. CON sows were more likely to have a pressure sore compared to SPE sows (P = 0.02); PE sows tended to have a higher likelihood of developing a pressure sore than SPE sows (P = 0.097). No treatment effect was found on salivary cortisol for sows or nursery piglets. However, CON piglets had the largest tear stains during lactation (P < 0.001) and nursery (P = 0.001). Treatment affected piglet skin lesions during lactation, with CON piglets having more ear (P < 0.001) and front lesions (P = 0.002) and a higher overall lesion score (P < 0.0001). No treatment effect was found on ADG, piglet crushing, or nursery skin lesions. In conclusion, enrichment strategies in farrowing crates improved piglet skin health and tear stains without affecting performance. Enrichment access for sows tended to reduce pressure sores, suggesting enrichments can enhance welfare in farrowing crate systems.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"19 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144533349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dietary L-Glutamine Supplementation Enhances Growth Performance and Carcass Characteristics in Hanwoo Heifers via Hepatic and Skeletal Muscle Gene Regulation.","authors":"Xue-Cheng Jin,Jin-Soo Park,Dong-Qiao Peng,Won-Seob Kim,Jae-Sung Lee,Hong-Gu Lee","doi":"10.1093/jas/skaf215","DOIUrl":"https://doi.org/10.1093/jas/skaf215","url":null,"abstract":"Given the important roles of L-glutamine (L-Gln) in protein synthesis and energy metabolism, we hypothesized that L-Gln supplementation could improve growth performance and carcass characteristics in Hanwoo heifers. This study aimed to investigate the effects of L-Gln supplementation on growth performance, carcass characteristics, and gene expression in the liver and skeletal muscle of Hanwoo heifers. A total of 44 Hanwoo heifers (age: 23.7 ± 0.7 mo; body weight [BW]: 458 ± 68 kg) were allocated to three dietary treatment groups using a randomized block design, with the experimental start date as the blocking factor. The dietary treatments included L-Gln supplementation through top dressing based on the dry matter feed at 0% (n = 13), 0.25% (n = 16), and 0.5% (n = 15). The treatment lasted for 195 d (6.5 mo), followed by slaughter. Hematological parameters, growth performance, carcass characteristics, and gene expression in the liver and skeletal muscle samples obtained from the carcass were evaluated. Statistical analyses were performed using the MIXED procedure of SAS 9.4, with L-Gln supplementation as a fixed effect and block as a random effect. The 0.25% L-Gln group showed a significant increase (P < 0.05) in final BW, carcass weight, ribeye area, and fat color compared to the 0% group. In the liver, the expression of glutaminase 2 (GLS2) was significantly decreased (P < 0.05) in both the 0.25% and 0.5% L-Gln groups. Furthermore, the 0.5% L-Gln group exhibited lower (P < 0.05) expression levels of pyruvate carboxylase (PC), phosphoenolpyruvate carboxykinase 1 (PCK1), and phosphoenolpyruvate carboxykinase 2 (PCK2). The expression of glucose-6-phosphatase catalytic subunit 1 (G6PC1) also decreased (P < 0.05) in the 0.25% L-Gln group. In the skeletal muscle, myogenic differentiation 1 (MYOD) expression was significantly higher in the 0.25% L-Gln group, while the 0.5% L-Gln group showed higher zinc finger protein 423 (ZNF423) expression (P < 0.05). Additionally, the expression levels of myogenin (MYOG), heat shock protein beta-1 (HSPB1), CCAAT enhancer binding protein alpha (CEBPA), and fatty acid binding protein 4 (FABP4) were increased (P < 0.05) in both the 0.25% and 0.5% L-Gln groups. Overall, dietary supplementation with 0.25% L-Gln improved the final BW, carcass weight, and ribeye area in fattening Hanwoo heifers, which is possibly related to the regulation of myogenic genes, HSPB1, and enzymes involved in hepatic Gln metabolism and gluconeogenesis.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"51 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144533354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insulin-sensitizing effects of fibroblast growth factor-21 in underfed sheep","authors":"Antonio Carlos Ramos dos Santos, Molly M McGuckin, Sarah L Giesy, Yves R Boisclair","doi":"10.1093/jas/skaf217","DOIUrl":"https://doi.org/10.1093/jas/skaf217","url":null,"abstract":"Reversal of insulin resistance by fibroblast growth factor-21(FGF21) in rodent and non-human primate models of obesity and in well-fed sheep was associated with increased production of the insulin-sensitizing hormone adiponectin. In contrast, FGF21 therapy failed to increase plasma adiponectin and improve insulin action in energy-deficient ruminants facing metabolically demanding states such as early lactation dairy cows. The goal of the study was to test the hypothesis that FGF21 is unable to improve insulin action in energy-deficient ruminants as a consequence of its failure to increase plasma adiponectin. Non-pregnant, non-lactating ewes were treated for 12 days with FGF21 or excipient when well-fed (WF; 2-fold of maintenance energy requirement, n=4) or underfed (UF; 0.5-fold of maintenance energy requirement, n=4). Plasma variables were measured as indices of insulin action (glucose, insulin and adiponectin), lipolysis (fatty acids), and ketogenesis (β-hydroxybutyrate) on day 1, 4, 7, 10, and 12 of treatment. The effect of treatments on insulin action was assessed by measuring glucose disposal during insulin tolerance tests on day 10 and glucose tolerance tests on day 11. Quantitative RT-PCR was used to measure expression of genes mediating FGF21 effects in adipose tissue. Underfed ewes lost weight (EB, P &amp;lt; 0.01) and had reduced plasma glucose (EB, P = 0.04) and insulin (EB × Day, P = 0.01), confirming negative energy balance. In UF ewes, FGF21 retained the ability to reduce plasma glucose (FGF21, P = 0.02) but not plasma insulin. FGF21 improved insulin action in both WF and UF ewes during glucose (insulin response area; FGF21, P = 0.02) and insulin tolerance tests (FGF21, P = 0.04) and did so in the absence of increased plasma adiponectin in UF ewes. Underfeeding reduced adipose tissue expression of the FGF21 co-receptor β-Klotho (EB, P &amp;lt; 0.01) and attenuated FGF21 stimulation of the FGF-responsive genes SPRY4 (EB × FGF21, P = 0.07) and DUSP4 (EB × FGF21, P = 0.02). FGF21 failed to increase adiponectin mRNA expression at both feeding levels. FGF21 had no effect on plasma fatty acids but reduced plasma β-hydroxybutyrate in UF ewes (EB × FGF21, P = 0.02). These data show that energy insufficiency alone does not prevent FGF21 improvement of insulin action in ruminants and that increased adiponectin production is not necessary for FGF21 insulin-sensitizing effects.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"47 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144533123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of gastrointestinal and fecal microbial communities as markers of liver abscess risk in beef feedlot cattle","authors":"J Daniel Young, Kasi N Schneid, Lee J Pinell, Cory A Wolfe, Ty E Lawrence, Kendall L Samuelson, John T Richeson, Paul S Morley","doi":"10.1093/jas/skaf210","DOIUrl":"https://doi.org/10.1093/jas/skaf210","url":null,"abstract":"Liver abscesses (LAs) are a prevalent and costly issue in the beef industry. Microbial translocation from the gastrointestinal tract is believed to be the underlying cause of LAs. However, little is understood about the factors that permit passage of bacteria into the portal bloodstream, or where this translocation is likely to occur. This study used 16S rRNA gene sequencing to characterize the microbial community composition of the rumen, small intestine, large intestine, and feces of steers with edible and abscessed livers of varying severity. The small intestine of steers with severe LAs had increased (P = 0.02) richness and evenness compared to cattle with edible livers. However, there were no differences in the alpha diversity among samples collected at other locations (P ≥ 0.08). Small intestine samples also had a reduced (P &amp;lt; 0.01) Firmicutes to Bacteroidota ratio for cattle with LAs compared to those with edible livers. Prevotellaceae and Synergistaceae family abundance differed in the small intestine of cattle with LAs. Differences in community composition were not identified in fecal, colon, or rumen samples in association with LA occurrence, and there were no differences related to bacteria that have been traditionally considered LA pathogens (e.g., Fusobacteria or Trueperella spp.). These findings suggest that the microbial communities of the small intestine may have an important influence on LA occurrence. However, differences in microbial communities were not identified in rumen and fecal samples that might be used in predicting LA occurrence. Although sampling techniques during the feeding period are still limited and advances in this area would greatly benefit LA research.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"54 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144503362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation of genetic parameters for mature cow size in North American and Australian Angus cattle","authors":"Ayooluwa O Ojo, Gabriel S Campos, Henrique A Mulim, Andre Garcia, Allan P Schinckel, Christian Duff, Steve Miller, Kelli Retallick-Riley, Hinayah R Oliveira","doi":"10.1093/jas/skaf212","DOIUrl":"https://doi.org/10.1093/jas/skaf212","url":null,"abstract":"Mature cow size can be effectively controlled through genetic selection. Understanding the genetic relationships between mature cow weight (MWT), mature cow height (MHT), and body condition score (BCS) is essential for implementing effective selection programs to enhance cow efficiency. The objectives of this study were to: 1) estimate variance components and genetic parameters for MWT, MHT, and BCS measured in the United States and Australia; 2) estimate the genetic correlation between these traits and early growth and carcass traits; and 3) estimate the genetic correlations among these traits across the two countries. The dataset provided by American Angus Association comprised of 434,746; 213,875; and 382,156 records for MWT, MHT, and BCS, respectively. The dataset provided by Angus Australia comprised of 206,003; 15,379; and 36,184 records for MWT, MHT, and BCS, respectively. Single-trait repeatability models were used to estimate heritabilities and multiple-trait models were used to estimate genetic correlations between traits and across countries. Heritabilities (SE) for MWT were 0.45 (0.005) and 0.40 (0.006); for MHT 0.57 (0.006) and 0.63 (0.02); and for BCS 0.18 (0.004) and 0.18 (0.01), in the US and Australia, respectively, highlighting their moderate-to-high genetic control. Genetic correlations within the US and Australian datasets between MWT and MHT, and MWT and BCS were &amp;gt; 0.50, and &amp;lt; 0.20 between MHT and BCS. Genetic correlations between MWT, MHT and early growth traits were generally positive and moderate-to-high, ranging from 0.51(0.01) to 0.92(0.003) in the US and 0.41(0.03) to 0.79(0.05) in Australia. Genetic correlations between BCS and early growth traits were in general positive (&amp;lt; 0.30), while genetic correlations between mature cow traits and ultrasound traits ranged from strong positive to strong negative. Genetic correlations between the traits in the two countries were high for MWT = 0.91 (0.02) and MHT = 0.97 (0.02); and moderate for BCS = 0.65 (0.08). Our results suggest that optimizing selection for mature cow traits is feasible, and that a joint evaluation between the US and Australia could be beneficial.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"18 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144513153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"168 Effect of cow metabolizable energy intake on calf growth performance in crossbred Angus beef cattle","authors":"Mariana Eloisa Garcia Ascolani, Courtney M Williams, Corbit L Bayliff, Ryan R Reuter, Gerald W Horn, Carla L Goad, David L Lalman","doi":"10.1093/jas/skaf170.036","DOIUrl":"https://doi.org/10.1093/jas/skaf170.036","url":null,"abstract":"A two-yr experiment was conducted to determine the impact of maternal metabolizable energy intake (MEI) on energy partitioning and performance of crossbred Angus cows and their calves. Forty mature crossbred Angus lactating beef cows (6±2 y, 534±60 kg BW) were used each year along with their suckling steer calves (84±9 d, 130±15 kg BW). Cows were stratified by early-lactation milk yield and randomly assigned to 1 of 5 levels of metabolizable energy intake. During yr 1, maternal MEI ranged from 225 to 320 kcal·BW0.75·d-1, while in yr 2, MEI ranged from 215 to 288 kcal·BW0.75·d-1. Calves received the same TMR diet as the cows via creep feeding ad libitum. Parameters evaluated included calf BW, ultrasound carcass characteristics, and calf creep feed intake. Data was analyzed using the GLIMMIX procedure of SAS (SAS Inst. Inc., Cary, NC). The final model included the linear effect of maternal metabolizable energy intake as a fixed effect and year of experiment as a random effect. Increasing maternal MEI did not affect rib eye area (P = 0.17) nor back fat (P = 0.22) although rump fat increased slightly (linear P = 0.05) at the rate of 0.1 cm per 100 kcal maternal MEI·BW0.75·d-1. Intramuscular fat tended (P = 0.10) to increase in a curvilinear fashion when the dam received &amp;gt;230 kcal·BW0.75·d-1. Calf BW adjusted to 100 d of experiment linearly increased (P = 0.03) by 0.185 kg per unit increase in maternal MEI, with ADG showing a similar trend (P &amp;lt; 0.01). Increasing maternal MEI linearly increased (P &amp;lt; 0.001) milk energy availability and therefore, it was assumed that energy intake from milk increased accordingly. While calf MEI from creep feed was not different (P = 0.12), MEI from milk linearly increased (P &amp;lt; 0.001) with increased maternal MEI. However, the overall energy efficiency of the calves was linearly and negatively affected (P = 0.03) with increasing maternal MEI: the overall efficiency of calf growth (g BW gain∙kcal MEI∙d-1) decreased by 12.7% when maternal energy intake was increased by 100 kcal·BW0.75·d-1, although this 100 kcal increase in maternal energy resulted in a 13% improvement in Calf ADG and a 30% increase in calf MEI. In conclusion, increasing maternal metabolizable energy intake (MEI) in beef cows had a minor effect on carcass characteristics and an overall positive impact on calf growth performance, but with diminishing returns in terms of energy efficiency. More work is needed to characterize these relationships during early lactation and given a wider range in both maternal MEI and genetic capacity for milk yield.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"630 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144500585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"159 Effects of artificial shade and chromium supplementation during mid and late gestation of beef cows under heat stress: cow performance and thermotolerance","authors":"Ronaldo Gomes, Isabelle Siqueira, Hiam Marcon, João Chinaglia, Marcelo Vedovatto, Barbara Roqueto do Reis, Ashley K Edwards, Matheus Fellipe Lana Ferreira","doi":"10.1093/jas/skaf170.098","DOIUrl":"https://doi.org/10.1093/jas/skaf170.098","url":null,"abstract":"The objective of the study was to evaluate the effects of the provision of artificial shade and chromium (Cr) supplementation during mid and late gestation on the performance and thermotolerance of beef cows. At 150 ± 20 d days prepartum (day 0), 72 fall-caving Angus-cross cows were stratified by body weight (BW; 566 ± 5.38 kg) and body condition score (BCS; 6.3 ± 0.5) and allocated into 1 to 12 bermudagrass pastures (3 to 5 ha pastures/5 or 7 cows per pasture). Treatments were randomly assigned to pastures in a 2 × 2 factorial: shade and Cr (SC), no shade and Cr (NSC), shade and no Cr (SNC) and no shade and no Cr (NSNC), applied from day 0 to 150 days before calving. Shade was provided by artificial structures made from black polypropylene fabric, with 4.2 m² of shaded area per animal/pasture. Chromium (Cr propionate; KemTRACE Chromium 0.4%, Kemin Industries) was added to a free choice mineral mix (target intake of ~100 g/day/cow) to provide 0.5 mg Cr/kg of total diet. Body weight and BCS were measured on day 0, 30, 60, 90 and 120 pre-calving. Respiration rate and body surface temperature (BS) were measured every 15 days. Body surface temperature was collected individually using an infrared camera. On day 60 the intravaginal temperature of the cows was recorded every 30 minutes during 7 days through a data logger. Dry-bulb temperature and relative humidity were recorded through a data logger to obtain the temperature-humidity index (THI) throughout the study. The data was analyzed using the mixed procedure in SAS 9.4. The pasture was the experimental unit in all analyses, with the animal (treatment) included as a random effect. Significance was defined as P ≥ 0.05, and tendency when 0.05 &amp;gt; P ≤ 0.10. Interaction between Shade × Cr × Day was found for BW (P &amp;lt; 0.05), where cows from treatment Shade-Cr showed greater BW on 90 and 120 compared to the other treatments. An interaction between shade × day was found for BCS (P &amp;lt;.0001), where both shaded treatments had greater BCS from d 30 to 120 than treatments without shade. Interaction between shade and hours of day was found (P &amp;lt;.0001) where cows from shade treatment had reduced IT from 9:00 am to 7:00 pm. Shade reduced RR and BS (P &amp;lt;.0001). A Cr × day interaction (P &amp;lt; 0.01) was observed for RR, where Cr increased RR on days 30, 75, and 90. These results indicate that providing artificial shade helped beef cows under heat stress conditions maintain BCS and reduce IT and BS. The combination of artificial shade and Cr supplementation improved cows BW.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"17 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144500587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"176 Performance, digestion, and passage of whole cottonseed offered either as libitum or under restriction to beef cows nursing calves","authors":"Chandler Kyle, Diva N Rigney, Duncan McSorley, Mason B Henson, Paul W Dyce, Kimberly Mullenix, Leanne Dillard, Brandon B Smith","doi":"10.1093/jas/skaf170.029","DOIUrl":"https://doi.org/10.1093/jas/skaf170.029","url":null,"abstract":"In the southeastern U.S., whole cottonseed (WCS) is a readily available, nutritious, and cost-effective feedstuff for beef cattle. The NCR (2016) estimates that whole cottonseed contains approximately 52% neutral detergent fiber (NDF), 24% crude protein (CP), and 18% crude fat. Feeding recommendations on feeding WCS in beef cattle systems were developed in the 1980’s based on the whole cottonseed quality of that time. Based on recent studies, we have demonstrated changes in seed quality in the Southeast due to the development of new varieties. Therefore, the purpose of this study was to determine WCS supplementation rates in beef cow diets based on industry changes in cottonseed quality, especially in the Southeast. The experiment was conducted as a generalized complete block design with two feeding pens (blocks) of eight cow-calf pairs each. Cow-calf pairs were then randomly allocated into four treatments: a negative control receiving bermudagrass (BG) hay (CON), BG plus supplemental WCS at 15% targeted dry matter intake (DMI), BG plus WCS to achieve a crude fat allowance of 4% dry matter intake (FAT), and BG plus ad libitum supplemental WCS (LIB). Cows offered LIB consumed the most WCS (P &amp;lt; 0.01; 7.9 kg/d), followed by FAT (3.3 kg/d), then DMI (1.8 kg/d). However, total daily intake was greatest (P = 0.03) from CON (14.9 kg/d) and LIB (13.7 kg/d) and least from DMI (10.3 kg/d), with FAT intermediate (12.4 kg/d). There was no effect of treatment on dam milk production (P = 0.60) nor calf ADG (P = 0.47). Results are interpreted to mean that WCS may be offered beef cows nursing calves at levels approaching ad libitum consumption without adverse responses, though this may not achieve economic production goals.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"27 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144500630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PS-9 Behavioral patterns at the feed bunk as indicators of feed efficiency in yearling Angus bulls","authors":"Amelia R G Katz, Jason P Dubowsky, Julie M Huzzey, Zachary D McFarlane","doi":"10.1093/jas/skaf170.187","DOIUrl":"https://doi.org/10.1093/jas/skaf170.187","url":null,"abstract":"The objective of this study was to evaluate the relationship between feed efficiency and feeding behavior in yearling Angus bulls. Bulls (n=214) were housed at Cal Poly Bull Test across 4 similar pens with 24-28 bulls/pen and a stocking rate of 6-7 bulls/feeder. Pens were balanced based on bull body weight at the start of the trial. This trial was repeated over two years with different sets of bulls. Feeders were filled twice daily at approximately 0630 h and 1700 h. Feed intake was monitored using an automated system (SmartFeed, C-Lock, Inc.) that recorded entry and exit times, as well as feed start and end weights. Data were processed to calculate for each bull: visit frequency, visit duration, total feeding time, and hourly feed intake during the 85-day trial. Bulls were retrospectively classified into high feed efficiency (HIFE) and low feed efficiency (LOFE) treatment groups based on their combined residual feed intake and feed:gain ratio ranks. Five bulls from each treatment group were selected per pen per year, resulting in 40 bulls per treatment for analyses. Data were analyzed using the MIXED procedure in SAS 9.4. The model included fixed effects of feed efficiency group, hour (0 to 24), and their interaction, with bull within pen as a random effect and hour treated as a repeated measure. LOFE bulls visited the feeder more frequently throughout the day (P = 0.0001) and consumed more feed overall (P &amp;lt; 0.0001), particularly around feed delivery times (P &amp;lt; 0.04). LOFE bulls spent more time feeding across the entire day (P = 0.002) but did not differ from HIFE bulls in visit duration per feeding event (P = 0.35). Differences in feeding patterns were most evident around feed delivery times, with LOFE bulls displaying longer feeding durations and higher feed intake during the hours surrounding both morning and evening feed deliveries (P &amp;lt; 0.03). These findings demonstrate distinct behavioral differences between feed efficiency groups, particularly around feeding times. Bulls with higher feed efficiency exhibited more restrained feeding behavior, characterized by fewer visits and reduced feed intake. This suggests that behavioral patterns at the feed bunk could serve as an important criterion in bull selection for feed efficiency improvement.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"39 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144500639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"92 Effects of an acclimation protocol during the handling events of the 7-day CO-Synch + CIDR protocol on temperament and reproductive performance of Bos taurus beef heifers","authors":"Sydney H Flax, Danielle M Stock, Allen G Schwartz, Jack Lemmon, Joao V C Silva, Santiago P Hurtado, Andreia F Machado, Victor Gomez-Leon, John R Jaeger, Nicola Oosthuizen, K C Olson, Felipe A C C Silva, Sandy Johnson, Nicholas Wege Dias","doi":"10.1093/jas/skaf170.068","DOIUrl":"https://doi.org/10.1093/jas/skaf170.068","url":null,"abstract":"It has been previously demonstrated that heifers with excitable temperament have greater cortisol concentrations and decreased conception rates to timed-artificial insemination (TAI). Nevertheless, cortisol concentrations are decreased as the handling events of an estrus synchronization protocol (ES) progress. The objectives of this study were to investigate the effects of acclimating heifers to the facility during the handling events of an ES protocol on temperament and conception rates to TAI. Prior to enrollment in the study (Day -10), 622 Bos taurus commercial beef heifers from five locations in the Spring of 2023 and three locations in the Spring of 2024 were evaluated for reproductive tract scores (RTS), chute score (CS), and exit velocity (EV). To determine RTS, the following scale was used based on uterine horn diameter and uterine tone: 1=immature, &amp;lt; 20mm diameter and no tone; 2=20-25mm diameter and no tone; 3=20-25mm diameter with slight tone; 4=30mm diameter with good tone; 5= &amp;gt;30mm diameter with good tone. Chute scores were recorded on a scale where 1=calm and motionless; 2=restless movements; 3=frequent movement and vocalization; 4=constant movement, vocalization, shaking, and struggling; 5=violent and continuous struggling. Exit velocity was measured using an infrared sensor. Heifers were stratified based on CS and RTS to be acclimated to the handling facility during the handling events of the ES (TRT; n=307) or serve as control (CTRL; n=315), tagged accordingly and managed as one group. All heifers were enrolled in the 7-day CO-Synch + CIDR protocol and received TAI. Before the ES protocol handling events (Days 0, 7, and 10), TRT heifers were sorted off and acclimated to the handling facility by running them through the chute without restraint. After acclimation, they were commingled with CTRL heifers and returned to the facility for the subsequent ES event. To assess temperament, CS and EV were collected for all heifers on Days 0, 7, and 10 of the study. Estrus detection patches were placed on Day 7 and scored on Day 10. Pregnancy status was determined approximately 40 days post-TAI by transrectal ultrasonography. No treatment effects were observed for RTS (P=0.78), CS (P=0.42) and EV (P=0.17) on Day -10. Exit velocities decreased as the protocol progressed for all heifers (P&amp;lt; 0.0001), but did not differ between treatments (P=0.27). Additionally, no difference was observed for estrus patch scores (P=0.46) between treatments. However, TRT heifers had decreased CS on Day 10 when compared to CTRL (P=0.001) and greater conception rates to TAI (54% for TRT and 45% for CTRL; P=0.02). These results suggest that acclimating heifers to the facility during the handling events of the 7-day CO-Synch + CIDR estrus synchronization protocol led to improved chute scores, indicating a potential improvement in temperament, and effectively improved conception rates to TAI.","PeriodicalId":14895,"journal":{"name":"Journal of animal science","volume":"13 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144503366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}