JDS communications最新文献

{"title":"Efficacy of methods to synchronize follicular wave emergence in pregnant heifers","authors":"Cameron B. Hayden ,&nbsp;Jessica C.L. Motta ,&nbsp;Rodrigo V. Sala ,&nbsp;Nora M. Bello ,&nbsp;Marco A. Coutinho da Silva ,&nbsp;Alvaro García-Guerra","doi":"10.3168/jdsc.2024-0629","DOIUrl":"10.3168/jdsc.2024-0629","url":null,"abstract":"<div><div>The objective of the present study was to evaluate the efficacy of various methods for synchronization of follicular wave emergence (FWE) in pregnant heifers. Pregnant (60 d of gestation) Holstein heifers (n = 86) arranged in cohorts were randomly assigned to be administered 172 µg of gonadorelin acetate (GnRH), 3,300 IU of human chorionic gonadotropin (hCG), follicular ablation of follicles &gt;5 mm (FA), or saline (control). Ultrasonography was performed to determine ovulation and emergence of a new follicular wave. Data were analyzed using generalized linear mixed models with treatment as a fixed effect and cohort as a random effect. Ovulatory response was greater for hCG (81.0%; 95% CI: 58.0–92.9) than GnRH-treated (50.0%; 95% CI: 28.8–71.2) heifers, whereas ovulation was not observed for heifers in the FA or control groups. Heifers in the FA group had a shorter (34.8 ± 1.7 h) interval from treatment to FWE compared with heifers in the hCG (51.8 ± 5.3 h), GnRH (56.8 ± 5.3 h), and control (61.4 ± 9.8 h) groups. Furthermore, treatments differed in variability of time to FWE, whereby FA-treated heifers had less variable, more consistent responses than hCG and GnRH heifers. These groups were, in turn, less variable in time to FWE than heifers in the control group. Synchronization of FWE efficacy was greater in FA (97.6%; 95% CI: 69.8%–99.9%) and hCG-treated (75.0%; 95% CI: 52.8%–89.0%) heifers than control (27.5%; 95% CI: 12.2%–50.9%) heifers, with marginal evidence for a difference between GnRH (69.1%; 95% CI: 46.4%–85.2%) and control heifers. Overall, we found no evidence for differences in FWE synchronization efficacy between hCG, GnRH, and FA. Nevertheless, FA resulted in a shorter and less variable interval from treatment to FWE, thus providing a more precise control of follicular development.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 154-159"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11770303/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics of automated body condition scores in grazing Holstein cows in a year-round calving system","authors":"C. Hernández-Gotelli ,&nbsp;R. Pommiez ,&nbsp;F. Aceituno ,&nbsp;P. Pinedo","doi":"10.3168/jdsc.2024-0619","DOIUrl":"10.3168/jdsc.2024-0619","url":null,"abstract":"<div><div>This observational study aimed to characterize the seasonal dynamics of automated BCS throughout the lactation of Holstein cows in a pasture-based system with year-round calvings. Examining the association between nadir BCS (nBCS; defined as the lowest daily BCS after calving) and peak milk yield within each calving period (calendar seasons equally divided in early and late) was a secondary objective of this research. Retrospective data included 2,164 lactations in 539 primiparous (PRI) and 1,625 multiparous (MLT) Holstein cows that calved from July 2021 to June 2023 in a commercial dairy farm located in Southern Chile. Individual BCS were generated in every milking by an automated BCS camera system. Body condition score at calving (BCSc), nBCS, and the change in BCS from calving to nadir (ΔBCS) were considered for the analysis. Peak milk yield (greatest daily milk yield) values were retrieved from on-farm software and lactations were categorized considering quartiles (Q1 = 25% lowest peak milk yield; Q4 = 25% greatest peak milk yield). Data were examined in PRI and MLT cows separately using multivariable linear models that considered calving period and peak milk yield as the main explanatory variables of interest, whereas BCSc and health status were included as covariables when appropriate. The differences in BCSc among calving periods were more evident in primiparous cows that had the lowest BCSc in early spring (3.13 ± 0.03; ± SE) and the greatest BCSc in late fall (3.51 ± 0.03). In MLT cows, the lowest and greatest BCSc were recognized in late fall (3.07 ± 0.04) and early summer (3.23 ± 0.03), respectively. Only MLT cows had differences in nBCS and ΔBCS across calving periods: The lowest nBCS were identified in late spring (2.71 ± 0.02), early summer (2.71 ± 0.02), and late summer (2.71 ± 0.02). The greatest losses in BCS also occurred in early summer (−0.41 ± 0.02) and in late spring (−0.41 ± 0.02). Time from calving to nBCS varied among calving periods and depended on parity category. Primiparous cows reached nBCS earlier in late summer (65 ± 8 DIM) and late spring (68 ± 7 DIM), whereas MLT had the shortest times to nBCS in late and early fall (67 ± 5 DIM; 68 ± 5 DIM). Greater values at milk peak were associated with lower nBCS only in multiparous cows during the late spring period. We concluded that the dynamics of BCS were associated with calving period in both parity groups. These data could help guide decisions on nutrition and breeding strategies in farms facing comparable conditions.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 110-116"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11770315/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dairy cow performance and nutrient utilization when offered high or low digestibility grass silages at 2 levels of total diet crude protein","authors":"A. Craig ,&nbsp;A.W. Gordon ,&nbsp;C.P. Ferris","doi":"10.3168/jdsc.2024-0606","DOIUrl":"10.3168/jdsc.2024-0606","url":null,"abstract":"<div><div>The hypothesis of this study was that grass silage digestibility would influence the response of dairy cows offered diets differing in CP content. Thirty-two mid-lactation Holstein dairy cows were used in a 2-period (21-d adaption phase, 7-d measurement phase), partially balanced change-over experiment. Four treatments were organized in a 2 × 2 factorial arrangement, comprising 2 grass silages differing in digestible OM in the DM (D-value; 748 and 668 g/kg DM, high-D and low-D, respectively) and 2 total diet CP levels (target 145 and 175 g/kg DM, high CP and low CP, respectively). The latter were achieved using 2 iso-energetic concentrates that differed in CP level (173 and 228 g/kg DM). Silages and concentrates were mixed and offered as a TMR in a 50:50 DM ratio. At the end of the feeding study, nutrient utilization was measured using 4 cows per treatment. Except for milk urea nitrogen there were no interactions between silage digestibility and total diet CP for cow performance and nutrient utilization. The high-D silage improved cow performance and increased nitrogen use efficiency (NUE). Reducing total diet CP also increased NUE, but there were negative impacts on cow performance. While there were benefits of offering grass silage with a high digestibility, responses to total diet CP were similar at both levels of silage digestibility.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 49-53"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11770310/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal patterns of liver and adipose lipase abundance across the periparturient period in multiparous Holstein dairy cows","authors":"S.J. Kendall ,&nbsp;H.T. Holdorf ,&nbsp;R.S. Pralle ,&nbsp;H.M. White","doi":"10.3168/jdsc.2024-0613","DOIUrl":"10.3168/jdsc.2024-0613","url":null,"abstract":"<div><div>Lipases such as patatin-like phospholipase domain-containing protein 3 (PNPLA3) exist in multiple tissue types. In subcutaneous adipose tissue, PNPLA3 was not altered during the periparturient period. Conversely, strong associations between liver PNPLA3 and liver triglyceride content peripartum were identified and confirmed to be causative using knockdown approaches in a primary bovine hepatocyte model. The objective of this research was to characterize adipose and hepatic lipase abundance, as well as abundance of hepatic transcription factors (TF) involved in adipose and liver tissue lipolysis to determine potential impact on bovine fatty liver development and recovery. Adipose and liver tissue biopsy samples were collected from −28 to +56 d relative to calving (DRTC) from multiparous Holstein dairy cows randomly assigned to either a control (CTL) or ketosis induction protocol (KIP) diet. Clinical ketosis (blood BHB ≥ 3.0 m<em>M</em>) was used as a cowside indicator of successful induction and was achieved in CTL (n = 2) and KIP (n = 12) cows. Both adipose and liver abhydrolase domain-containing protein 5 and adipose triglyceride lipase (ATGL) differed across DRTC, as did liver perilipin 1. Hepatic mature and immature carbohydrate response element binding protein, and sterol regulatory binding protein 1c, varied or tended to vary across DRTC × treatment. Neither adipose nor liver hormone sensitive lipase (HSL) were responsive to treatment or varied across DRTC, but adipose HSL was positively associated with nonesterified fatty acids at +1 DRTC. Adipose and liver ATGL was associated with liver triglycerides across all DRTC. Patterns of adipose HSL and ATGL abundance did not explain the increase in nonesterified fatty acids observed at +1 DRTC in this study. Future investigation of lipase abundance in other adipose tissue depots is still needed to better explain regulation during this time. Bovine fatty liver development and recovery appears to be contingent upon liver PNPLA3 abundance, rather than liver ATGL.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 143-148"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11770316/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insulin, IGF-I, and lactoferrin concentrations and yields and their associations with other components within colostrum, transition, and whole milk of primiparous and multiparous Holstein cattle","authors":"A.J. Fischer-Tlustos ,&nbsp;S.L. Cartwright ,&nbsp;K.S. Hare ,&nbsp;D.J. Innes ,&nbsp;J.P. Cant ,&nbsp;M. Tortades ,&nbsp;F. Fabregas ,&nbsp;A. Aris ,&nbsp;E. Garcia-Fruitos ,&nbsp;M.A. Steele","doi":"10.3168/jdsc.2024-0572","DOIUrl":"10.3168/jdsc.2024-0572","url":null,"abstract":"<div><div>The primary objective of the study was to characterize concentrations and yields of lactoferrin (LF), insulin, and IGF-I in colostrum, transition milk (TM), and whole milk (WM) of multiparous (MP) and primiparous (PP) cows. A secondary objective was to determine associations between colostrum and TM components (fat, protein, lactose), IgG, and bioactive compounds (oligosaccharides, LF, insulin, IGF-I; defined as compounds present in micro quantities that stimulate physiological responses systemically or locally within the neonate). Holstein cows (10 MP and 10 PP) were assigned to the study at calving and colostrum was collected 5.3 ± 0.7 h (mean ± SE) after calving, followed by twice daily sampling of milkings 2–5 (TM) and milking 12 (WM). Colostrum, TM, and WM samples were analyzed by commercial ELISA to determine concentrations of LF, insulin, and IGF-I. Concentrations of insulin, IGF-I, and LF were greatest in colostrum compared with all other milkings. Similarly, IGF-I and LF yields were greatest in colostrum, whereas insulin yield was greatest in colostrum and milking 2 compared with milking 4, 5, and 12. Primiparous cows had greater insulin and lower LF concentrations in colostrum compared with MP cows. Additionally, lower LF concentrations in PP cows persisted through milkings 2 and 3. The majority of associations between components and bioactive compounds in colostrum were positive; however, correlations were different between PP and MP cows. Specifically, there were a greater number of strong (ρ &gt; 0.80) correlations between components and IgG in PP cows. In contrast, MP cows demonstrated a greater number of strong correlations among bioactive compounds. To the authors' knowledge, this study is the first to characterize the yields of IGF-I, LF, and insulin during the colostral (collection within 6 h) and TM period in both MP and PP cows. The study findings indicate that parity influences the levels of LF and insulin, but not IGF-I. Our study also uniquely demonstrates associations between early lactation components and bioactive compounds, which are not consistent among parities.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 137-142"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141712594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Increased expression of interferon-stimulated gene 15 (ISG15) in cervical cells on day 14 of pregnancy in Holstein heifers","authors":"Graciana R. Mendina ,&nbsp;Victoria de Brun ,&nbsp;Maria de Lourdes Adrien ,&nbsp;Victoria Pons ,&nbsp;Rodrigo Vivian Paradizo ,&nbsp;Jorge Gil ,&nbsp;Cecilia C. Rocha ,&nbsp;Mario Binelli ,&nbsp;Ana Meikle","doi":"10.3168/jdsc.2024-0596","DOIUrl":"10.3168/jdsc.2024-0596","url":null,"abstract":"<div><div>In cattle, expression of IFN-stimulated genes in the female reproductive tract has been reported as an early pregnancy diagnostic tool, as early as d 17 of pregnancy. The hypothesis of this study was that expression of <em>ISG15</em> in the cervix of pregnant heifers is increased on d 14 of pregnancy. The objective was to compare the expression of <em>ISG15</em> in cervical cells between pregnant and cyclic heifers (control, sham-inseminated) on d 14, 16, and 18 after insemination (d 0). Holstein heifers were submitted to an estrus synchronization protocol and inseminated with extender only (“control,” n = 6), or with regular semen (n = 15). Heifers were classified as pregnant (n = 10) by ultrasound at d 30 through the detection of a viable embryo with a heartbeat. Blood samples from the coccygeal vein were collected to determine serum progesterone concentrations on d 14, 16, and 18. The expression of <em>ISG15</em> and <em>PGR</em> in cervical cells collected through cytobrush was measured on d 14, 16, and 18. A receiver operating characteristic (ROC) curve was calculated to quantify the pregnancy diagnostic accuracy of <em>ISG15</em> and <em>PGR</em> expression. The expression levels of <em>ISG15</em> in cervical cells were significantly greater in pregnant compared with control heifers on d 14, and remained greater on d 16 and 18, whereas differences in PGR were observed only on d 18. Scatter plots and ROC analyses showed the most accurate prediction of pregnancy for <em>ISG15</em> on d 16. In conclusion, cervical cells express greater <em>ISG15</em> mRNA in pregnant versus control heifers as early as d 14 postinsemination, with the best accuracy on d 16.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 165-170"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11770300/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143060993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Weighted single-step genomic best linear unbiased predictor enhances the genomic prediction accuracy for milk citrate predicted by milk mid-infrared spectra of Holstein cows in early lactation","authors":"Y. Chen ,&nbsp;H. Atashi ,&nbsp;C. Grelet ,&nbsp;N. Gengler","doi":"10.3168/jdsc.2024-0607","DOIUrl":"10.3168/jdsc.2024-0607","url":null,"abstract":"<div><div>Previous studies have shown that milk citrate predicted by milk mid-infrared (MIR) spectra is strongly affected by a few genomic regions. This study aimed to explore the effect of weighted single-step GBLUP on the accuracy of genomic prediction (GP) for MIR-predicted milk citrate in early-lactation Holstein cows. A total of 134,517 test-day predicted milk citrate collected within the first 50 DIM on 52,198 Holstein cows from the first 5 parities were used. There were 122,218 animals in the pedigree, of which 4,479 had genotypic data for 566,170 SNPs. Two datasets (partial and whole datasets) were used to verify whether the accuracy of GP is improved using the following different methods. The (genomic) estimated breeding values (EBV or GEBV) in the partial and whole datasets were estimated by pedigree-based BLUP (ABLUP), single-step GBLUP (ssGBLUP, pedigree-genomic combined using no weight for SNP), and weighted ssGBLUP (WssGBLUP, pedigree-genomic combined using weighted SNP), respectively. The difference between the 2 datasets is that the phenotypic data from 2017 to 2019 in the partial dataset were set as missing values. One hundred eighty-one youngest cows with genomic data were selected as the validation population. A linear regression method was used to compare EBV (GEBV) predicted for partial and whole datasets. The accuracies of GP for ABLUP and ssGBLUP were 0.42 and 0.70, respectively. The accuracies of GP for WssGBLUP in the 5 iterations with different CT (constant) values (determines departure from normality for SNP effects) ranged from 0.70 to 0.86. This study showed that weighted SNP is beneficial in improving prediction accuracy for predicted milk citrate.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 90-94"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11770305/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of insoluble calcium content in Cheddar, feta, Juustoleipa, and mozzarella cheeses using acid-base buffering curves","authors":"Rachel Lindstrom,&nbsp;Prateek Sharma","doi":"10.3168/jdsc.2024-0561","DOIUrl":"10.3168/jdsc.2024-0561","url":null,"abstract":"<div><div>The amount of colloidal calcium phosphate (CCP) complex associated with caseins (insoluble [INSOL] Ca) determines the body, texture, flavor, and breakdown of cheese constituents during aging. The continuous pH decline during cheesemaking because of lactic acid fermentation results in solubilization of INSOL Ca. Measuring INSOL Ca in such a dynamic and wide range pH system (6.6 to 5.3) is challenging. The purpose of this study was to test utility of an acid-base auto-titration method in differentiating INSOL Ca content in cheeses with a wide range of pH (i.e., Juustoleipa 6.6, mozzarella 5.6, Cheddar 5.3, feta 4.8) and also to understand the relationship between pH, protein content, and INSOL Ca. A positive relationship was obtained for pH (R² = 0.62) and protein content (R² = 0.85) with INSOL Ca, suggesting concomitant release of CCP content at lower pH values and association of higher amount of CCP with higher protein content. Despite having a pH slightly closer to mozzarella (pH 5.56), Cheddar cheese (pH 5.25) had more INSOL Ca (0.67%) owing to the highest amount of protein (26%) and low moisture content (33%). Feta had the lowest amount of INSOL Ca (0.15%) owing to a low pH (4.79), higher moisture content (55%), and low protein content (14%). Juustoleipa had the highest percentage of INSOL Ca out of total Ca (88%) due to higher pH (6.62) and more intact casein. It was evident that the acid-base titration method was able to differentiate INSOL Ca between different types of cheeses with varying pH and protein content. Findings of this work will help tracking the proportion of INSOL Ca at various stages of cheesemaking and understanding kinetics of INSOL Ca solubilization and its role in causing pH variation in the early stage of cheese ripening.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 1-6"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141849567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An examination of the use of standard operating procedures on family-operated farms","authors":"M. Beecher,&nbsp;T. Lawton,&nbsp;C. Hogan","doi":"10.3168/jdsc.2024-0587","DOIUrl":"10.3168/jdsc.2024-0587","url":null,"abstract":"<div><div>Standard operating procedures (SOPs) can improve farm work organization by ensuring processes are standardized among the different people completing the same task. In this study, we examined the use of SOPs on family-operated farms and determined the influence of the number of people working on a farm on SOP use. A survey of 315 Irish dairy farms was completed examining the human resource and workload management practices; this study used a subset of questions from that survey. Of the 315 farms surveyed, the average herd size was 125 cows and there was 1 other person working with the farmer (range 0 to 5 people). Categorizing farms based on the number of people working on farm, 35% of the farms were owner-operators, 37% had 1 other worker, and 28% had 2 or more workers. Overall, 31.3% (n = 98) of all farms surveyed had written SOPs, whereas 68.7% (n = 217) had no written SOPs. Interest in ready-made SOPs among farmers was high (77%). Farms without SOPs found it significantly more difficult to write down work processes and lacked time to create SOPs compared with farms with SOPs. Standard operating procedures most frequently existed for milking (89%), management of fresh cows (35%), and reproduction (29%). Respondents indicated that consistency in work completion was the greatest benefit of having SOPs (39.8%; n = 39), followed by increase in efficiency (17.3%; n = 17) and health and safety (12.2; n = 12). Forty-three percent of farms with more 3 or more people had significantly more written SOPs present compared with 25% of owner-operator farms and 27% farms with 2 people. This research provides a greater understanding of the use of SOPs on family-operated dairy farms, highlighting that the presence of SOPs increases as the number of workers on farm increases.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 39-43"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11770289/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tissue-specific responses to oxidative fuel source preference during heat stress in lactating dairy cows","authors":"M.D. Ellett ,&nbsp;K.M. Daniels ,&nbsp;M.D. Hanigan ,&nbsp;B.A. Corl ,&nbsp;G. Perez-Hernandez ,&nbsp;C.L.M. Parsons ,&nbsp;J.A. Melvin ,&nbsp;D.W. Fausnacht ,&nbsp;R.P. McMillan ,&nbsp;L.H. Baumgard ,&nbsp;R.P. Rhoads","doi":"10.3168/jdsc.2024-0631","DOIUrl":"10.3168/jdsc.2024-0631","url":null,"abstract":"<div><div>Prolonged exposure to high environmental temperatures results in an accumulated heat load that induces a heat stress (HS) response in dairy cattle. Heat stress compromises dairy farm profitability by reducing milk yield, altering milk composition, and hindering reproductive performance. The ability to alternate between carbohydrate and lipid sources for energy production is termed metabolic flexibility (Met Flex). The objective of this study was to evaluate the Met Flex of mammary, muscle, and liver tissue in lactating dairy cows under HS and thermoneutral (TN) conditions. Sixteen Holstein cows were assigned to 1 of 2 treatment groups: pair-feeding in TN conditions (PFTN) or HS conditions. All cows experienced a 4-d TN period with ad libitum intake followed by a 4-d treatment period. Heat stress cows were exposed to a temperature-humidity index (THI) ranging from 76 to 80 and the PFTN cows were exposed to a THI of 64. Milk production and health data were recorded twice daily. Semitendinosus biopsies were obtained on d 4 of each period and postmortem mammary and liver samples were obtained on d 4 of period 2. All tissue samples were assayed for Met Flex. Activity of mitochondrial (Mit) enzymes were assessed in skeletal muscle only. Four days of HS decreased milk yield, altered milk composition, and increased respiration rate and rectal temperatures. No differences in Met Flex were observed in mammary or liver tissue during period 2. However, HS, but not PFTN conditions, lowered Met Flex of skeletal muscle by 18.3% when compared with TN ad libitum feed intake conditions of period 1. No treatment differences were observed in skeletal muscle Mit enzyme activity indicating the decrease in Met Flex occurred independently of changes in Mit function. The reduction in Met Flex of skeletal muscle during HS may contribute to reduced milk yield and warrants further investigation.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 1","pages":"Pages 160-164"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11770320/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}