JDS communications最新文献

{"title":"Effect of rumen-protected standardized dry grape extract supplementation on antioxidant and immune-related gene expression in leukocytes of mid-lactating Fleckvieh cows exposed to natural heat stress","authors":"Annalisa Amato,&nbsp;Carmelo Cavallo,&nbsp;Paul Engler,&nbsp;Hoa Bui,&nbsp;Mohammed el Amine Benarbia,&nbsp;Andrea Minuti,&nbsp;Erminio Trevisi,&nbsp;Anna Antonella Spina,&nbsp;Concetta Molè,&nbsp;Maria Giovanna Ciliberti,&nbsp;Marzia Albenzio,&nbsp;Luigi Liotta,&nbsp;Vincenzo Lopreiato","doi":"10.3168/jdsc.2026-1068","DOIUrl":"10.3168/jdsc.2026-1068","url":null,"abstract":"<div><div>Heat stress (HS) disrupts oxidative homeostasis and impairs immune function in dairy cows. In this context, plant polyphenols, when included in the diet, may modulate antioxidant defenses and immune response, including the antioxidant ability of leukocytes. This study evaluated whether supplementation with rumen-protected standardized dry grape extract (Nor-Grape BP-O; Nor-Feed) modulates antioxidant and immune-related gene expression in circulating leukocytes of mid-lactating Fleckvieh cows under natural HS. Thirty cows were randomly assigned to a control diet (CTR; n = 15) or to the same diet supplemented with 470 mg/cow per day of Nor-Grape BP-O (NG-BPO; n = 15) and monitored for 35 d during summer. Blood samples were collected at 0, 17, and 35 d for leukocyte isolation and quantitative PCR analysis. Relative gene expression was calculated using LinReg software and then transformed into ln fold change (lnFC) relative to 0 d. Data were subjected to PROC GLIMMIX procedure of SAS version 9.4 (SAS Institute). Overall, NG-BPO cows showed higher lnFC expression of glutathione peroxidase 1 (<em>GPX1</em>) and glutathione-disulfide reductase (<em>GSR</em>) than CTR cows. The lnFC superoxide dismutase 1 (<em>SOD1</em>) expression tended to be greater in NG-BPO cows compared with CTR cows, whereas superoxide dismutase 2 (<em>SOD2</em>) expression was unaffected by the supplementation. Among immune-related genes, interleukin-1β (<em>IL1B</em>) had an overall greater lnFC expression in NG-BPO cows, particularly at d 35, when a heat wave occurred, compared with CTR cows. A similar pattern was observed for lnFC interleukin-10 (<em>IL10</em>) expression, which was greater at 35 d in NG-BPO cows compared with CTR cows. In contrast, toll-like receptor 2 (<em>TLR2</em>), myeloid differentiation primary response 88 (<em>MYD88</em>), interleukin-1 receptor (<em>IL1R</em>), and glucose transporter 3 (<em>GLUT3</em>) were not affected by supplementation. The early upregulation of <em>GPX1</em> and <em>GSR</em> at 17 d suggests a transitory activation of oxidative detoxification pathway driven by polyphenols, followed by downregulation at 35 d. Concomitantly, the increased <em>IL10</em> and <em>IL1B</em> expression at 35 d in NG-BPO cows may suggest an enhanced capacity to regulate inflammatory signaling and maintain immune homeostasis, by preventing the negative effect of excessive immune activation. Overall, rumen-protected standardized dry grape extract supplementation was associated with a positive modulation of leukocyte genes involved in antioxidant defense system and regulation of inflammation, providing new molecular insight supporting previously reported improvements in physiological and immunometabolic responses during HS.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 684-690"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859123","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":"Measuring cytokines in quarter milk samples with a fluorescent bead-based multiplex assay","authors":"Anja Sipka,&nbsp;Matthias Wieland","doi":"10.3168/jdsc.2026-1038","DOIUrl":"10.3168/jdsc.2026-1038","url":null,"abstract":"<div><div>Mastitis is a highly prevalent, costly disease affecting well-being and productivity in dairy cows. Management of intramammary infections typically relies on aerobic culture for identification of a causative pathogen. Cytokines regulate inflammatory processes in the infected quarter. Their production and secretion patterns are influenced by the invading pathogen and by the host's immune system. A previously validated fluorescent bead-based multiplex assay was used for the quantification of bovine IL-10, TNF-α, and IFN-γ. Our goal was to demonstrate that this assay can be used for milk samples and to measure concentrations of the 3 analytes in quarter milk samples with different bacteriological culture results. We enrolled quarter milk samples that were submitted for routine mastitis diagnostics by farm personnel from commercial dairies (n = 17) in central New York. We selected samples identified with major mastitis pathogens, including coliform bacteria (n = 51; termed the coliform group, comprising <em>Escherichia coli</em> and <em>Klebsiella</em> spp.), bacteria from the <em>Streptococcus</em> family (n = 53; Strep group: <em>Streptococcus uberis, Streptococcus dysgalactiae</em>, and <em>Lactococcus</em> spp.), <em>Staphylococcus aureus</em> (n = 36; <em>S. aureus</em> group), samples from mastitic quarters without bacterial growth after 48-h aerobic culture (n = 44; no growth), and samples from healthy quarters (n = 55; healthy). When comparing cytokine concentrations for different bacteriological culture results, we found that the coliform group had the highest IL-10 and TNF-α concentrations compared with all other bacteriological culture results. The Strep group had higher IFN-γ and TNF-α concentrations compared with <em>S. aureus</em>, no growth, and healthy samples, and higher IL-10 concentrations compared with no growth and healthy quarters. No significant differences were found between <em>S. aureus</em>, no growth, and healthy samples, or between no growth and healthy samples. In this study we observed differences in cytokine concentration patterns across the selected bacteriological culture results. We demonstrated that the bovine multiplex assay can be used to measure IL-10, TNF-α, and IFN-γ in milk samples and could provide a useful tool for screening milk samples and furthering our understanding of inflammation dynamics in mastitis. Although differences were found between cytokine concentrations and bacteriological culture results, they showed high individual variation, and future studies should include additional information on enrolled samples such as occurrence of clinical signs, treatment, and resolution of infection.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 658-663"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859126","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":"Applicability of targeted metabolomics for the prediction of feed efficiency groups and metrics in dairy sheep","authors":"P.A.S. Fonseca,&nbsp;P. Frutos,&nbsp;L. Galucci,&nbsp;P.G. Toral,&nbsp;G. Hervás","doi":"10.3168/jdsc.2025-0905","DOIUrl":"10.3168/jdsc.2025-0905","url":null,"abstract":"<div><div>Identifying animals with high feed efficiency (FE) can significantly reduce production costs and environmental impact and improve profitability in livestock systems. Previous studies demonstrated that protein metabolism played a prominent role in predicting FE profiles in the Assaf breed. Consequently, a deeper investigation of the potential for protein-related metabolites to act as biomarkers for FE profile could help to determine a reduced subset of metabolites for FE prediction. In this study, 40 Assaf ewes were evaluated for FE using 2 metrics: residual feed intake (RFI) and feed efficiency index (FEI). Animals consistently classified at the extremes of both metrics were grouped as 6 lower (L-FE) and 6 higher (H-FE) FE individuals. Targeted plasma metabolomics, identified through ultra-performance liquid chromatography with multiple reaction monitoring tandem mass spectrometry with isotope-labeled target metabolites, was used to assess the potential of various metabolites related to protein metabolism to classify FE groups and predict FE metrics. Partial least squares discriminant analysis identified 9 metabolites with high variable importance in projection (&gt;1.5) that separated L-FE and H-FE groups. In leave-one-out cross-validation, the model based on the first principal component (PC1) achieved Pearson correlations of 0.745 for RFI and 0.920 for FEI with observed values. Subsequently, the dimensionality of these data was reduced via principal component analysis, and PC1 was used in linear models to predict RFI and FEI. The functional profile of the selected metabolites reinforced the central role of protein metabolism, especially AA transport and utilization, in shaping FE phenotypes in dairy ewes. These findings enhance our understanding of protein metabolism signatures linked to FE and support the development of cost-effective tools (when compared with whole metabolomics) for selecting high-efficiency animals in ruminant production systems.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 557-562"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859369","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":"Effect of intramammary infusion of a carvacrol-based botanical product at dry-off on udder health in organic-certified dairy cows","authors":"P. Muñoz-Boettcher,&nbsp;C. Hernandez-Gotelli,&nbsp;C. Ibarguren,&nbsp;R. Weng Zeng,&nbsp;J. Velez,&nbsp;A. De Vries,&nbsp;E. Miller-Cushon,&nbsp;B.J. Heins,&nbsp;R.A. Lynch,&nbsp;Q. Kolar,&nbsp;G.M. Schuenemann,&nbsp;V. Cabrera,&nbsp;E. Silva,&nbsp;P. Pinedo","doi":"10.3168/jdsc.2026-1039","DOIUrl":"10.3168/jdsc.2026-1039","url":null,"abstract":"<div><div>The aim of this study was to evaluate the effect of intramammary infusion of a carvacrol-based botanical product at dry-off on udder health during the subsequent lactation in Holstein cows managed in an organic-certified system. This randomized negative-controlled trial included 159 Holstein cows calving from May to December 2024 at a commercial organic dairy. Before the final milking before dry-off, composite milk samples were collected for SCC and bacteriological culture diagnosis. Immediately after milking, a carvacrol-based botanical product was intramammarily infused into each quarter in the treatment group, whereas distilled water was infused to the control group. Following calving, composite milk samples were collected during periods 1 (2–14 DIM) and 2 (15–30 DIM). Multivariable mixed linear regression models for repeated measures were used to assess the effect of treatment on log₁₀-transformed SCC (log₁₀SCC) during periods 1 and 2. Multivariable mixed logistic regression models for repeated measures were fitted to evaluate the effect of treatment on the probabilities of (1) bacteriological cure (negative culture) at period 1 in cows infected at dry-off and (2) new IMI at period 1 in cows not infected at dry-off, by treatment group. At dry-off, 47.2% of cows were uninfected, whereas 16.4% and 22.6% were infected with <em>Staphylococcus aureus</em> and <em>Staphylococcus chromogenes</em>, respectively. After calving, these percentages were 56.9%, 18.5%, and 13.9%, respectively. No differences in log₁₀SCC were observed between treatment groups during periods 1 and 2. Nevertheless, when comparing cows infected with <em>S. aureus</em> at dry-off, cows treated with the carvacrol-based botanical product showed higher log₁₀SCC values than those in the control group in period 2. Conversely, the probability of bacteriological cure in cows infected at dry-off with the 3 pathogen groups (<em>S. aureus</em>, <em>S. chromogenes</em>, other pathogens), as well as the probability of new IMI at period 1 in cows not infected at dry-off, were similar between the treatment and control groups. The results indicated that the carvacrol-based botanical product was not effective in reducing either the log₁₀SCC, the occurrence of new IMI, or the recovery of cows infected at dry-off. In conclusion, the intramammary infusion of a carvacrol-based botanical product at dry-off did not improve udder health in the subsequent lactation of dairy cows in an organic-certified system.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 631-637"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859654","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":"Spinose ear tick (Otobius megnini) infestation: Parasite burden and milk production response following permethrin aerosol in-ear treatment in a California dairy herd","authors":"P. Jardon,&nbsp;A. Rico,&nbsp;A. Gerry,&nbsp;B. Karle,&nbsp;N. Silva-del-Rio","doi":"10.3168/jdsc.2026-1020","DOIUrl":"10.3168/jdsc.2026-1020","url":null,"abstract":"<div><div>The spinose ear tick (<em>Otobius megnini</em>) is an ectoparasite of cattle whose impact on dairy production is poorly defined. This study evaluated the efficacy of a permethrin-based control protocol on tick burden and milk yield in Holstein cows under commercial California dairy conditions. Midlactation cows (n = 647) were systematically allocated to treatment groups by ear tag (odd or even) to receive either no treatment (CON; n = 300) or topical applications of permethrin aerosol spray (0.5%; ∼3 mL per ear; a 296-mL can treated approximately 50 cows) at wk 0 and 2 (TT; n = 347). Tick scores (TSc; 0 = none; 1 = 1–5; 2 = 6–10; 3 = &gt;10 ticks/ear) were assessed at baseline and at wk 2 and 3. Weekly milk yield was derived from automated parlor records for −7 to 28 d relative to treatment. Cumulative logit models were used to evaluate changes of TSc over time, and linear mix models adjusted for milk yield at baseline and pen were used to evaluate weekly milk-yield data. A significant reduction in TSc was observed for TT compared with CON, with a significant treatment × week interaction. The predicted probability of TSc = 0 (no ticks/ear) at wk 3 postintervention was 0.1% (95% CI: 0.0–0.2) for CON and 83.4% (95% CI: 75.9–88.9) for TT versus 0.3% and 1.2%, respectively at wk 0. After adjusting for baseline milk yield and pen, no treatment effect on weekly milk yield was observed: 39.7 versus 39.6 kg/d for CON and TT, respectively. Results demonstrated that permethrin aerosol effectively reduced spinose ear tick infestation but did not improve short-term milk production. This study provides field-based evidence that permethrin can substantially reduce tick burden in US dairy cattle and calls for longer-term studies evaluating production, welfare, and reinfestation outcomes.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 626-630"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859655","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":"Short-term milk production responses differ when balancing dietary 18-carbon fatty acids using high-oleic soybeans or a commercially available stearic acid-enriched supplement","authors":"Brooke A. Seelenbinder,&nbsp;Jair E. Parales-Girón,&nbsp;Alycia M. Bales,&nbsp;Adam L. Lock","doi":"10.3168/jdsc.2026-1022","DOIUrl":"10.3168/jdsc.2026-1022","url":null,"abstract":"<div><div>Recent evidence suggests that dietary 16- and 18-carbon fatty acids (FA) play an important role in influencing milk fat synthesis and nutrient partitioning. However, limited research has directly compared the effects of oleic- versus stearic-based supplemental sources under controlled conditions. We evaluated the effects of supplying 18-carbon FA primarily as oleic acid (<em>cis</em>-9 C18:1) from high-oleic soybeans versus stearic acid (C18:0) from a commercially available C18:0-enriched supplement, while balancing for similar 16-carbon FA intake, on short-term production responses in mid-lactation Holstein cows. Thirty-two cows were assigned to a 2-period crossover design with two 14-d periods, with sampling during the final 4 d of each period. Treatments were diets containing either 8% of diet DM as roasted, ground high-oleic soybeans (HOS) or 2% of diet DM as a C18:0-enriched supplement (SAT). High-oleic soybeans replaced soybean-based bypass protein to maintain similar overall dietary nutrient composition. Because inclusion of the C18:0-enriched supplement also increased dietary palmitic acid (C16:0), a C16:0-enriched supplement was added to the HOS diet to balance C16:0 supply and better isolate the effects of C18:0 versus <em>cis</em>-9 C18:1. The statistical model included cow within square as a random effect, and treatment, period, and square as fixed effects. Although diets were formulated to provide similar amounts of total and 16- and 18-carbon FA, analyzed FA profiles revealed that the C18:0-enriched supplement in SAT delivered a lower 18-carbon FA supply than its formulation values suggested. Compared with SAT, HOS reduced DMI (31.2 vs. 32.0 kg/d) but increased milk yield (50.8 vs. 49.0 kg/d), milk fat (2.05 vs. 1.97 kg/d), milk protein (1.59 vs. 1.52 kg/d), and lactose (2.49 vs. 2.39 kg/d). Accordingly, HOS increased 3.5% FCM by 2.3 kg/d, and ECM increased by 2.4 kg/d. A decrease in mixed FA yield was observed with HOS (721 vs. 778 g/d), along with an increase in preformed FA yield (717 vs. 614 g/d), consistent with the greater milk fat output. Body weight gain was also higher for HOS (0.78 vs. −0.01 kg/d), although the short evaluation period limits conclusions regarding longer-term effects. Collectively, these results indicate that feeding high-oleic soybeans, which mainly provide 18-carbon FA as <em>cis</em>-9 C18:1, led to better short-term milk production and component yields than using a commercially available C18:0-enriched supplement. These findings provide further evidence that individual 18-carbon FA exert different metabolic and production effects and should not be treated as interchangeable in diet formulation. More broadly, they highlight the value of accurate nutrient composition data in feed libraries and demonstrate that high-oleic soybeans may offer a practical on-farm alternative to certain commercially available fat supplements.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 569-574"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859690","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":"ER to: Effects of a novel onboard sorghum kernel processor and height of cut on berry processing score and ruminal in situ starch disappearance","authors":"Douglas Duhatschek,&nbsp;Artur Grando Pilati,&nbsp;Lyndon Luckasson,&nbsp;John Goeser,&nbsp;Elizabeth Coons,&nbsp;Luiz F. Ferraretto,&nbsp;Jourdan Bell,&nbsp;Jason K. Smith,&nbsp;Sushil Paudyal,&nbsp;Juan M. Piñeiro","doi":"10.3168/jdsc.2026-7-4-698","DOIUrl":"10.3168/jdsc.2026-7-4-698","url":null,"abstract":"","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Page 698"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859122","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":"Price discovery effects of Federal Milk Marketing Order modernization: Evidence from cheese survey and class I mover revisions","authors":"Avery J. Pound,&nbsp;Aidan T. Ainslie,&nbsp;Christopher A. Wolf","doi":"10.3168/jdsc.2026-1063","DOIUrl":"10.3168/jdsc.2026-1063","url":null,"abstract":"<div><div>Federal Milk Marketing Orders translate surveyed wholesale dairy commodity prices into minimum class prices and a pooled uniform price from which farm milk prices are constructed. Following a 2023–2024 hearing, the USDA's 2025 final rule introduced 5 categories of change to milk pricing. We focus on 2 changes with implications for price behavior and incentives: the cheese price survey eliminated 500-lb Cheddar barrels, using only 40-lb blocks, and the class I skim mover reverted to the <em>higher-of</em> the advanced class III or IV skim (with an extended shelf life adjuster). We find evidence that removing barrels, in isolation, is likely to modestly increase the price level in the cheese survey and derived protein series relative to combined blocks and barrels. We also conclude that returning to <em>higher-of</em> is likely to increase the average class I skim milk price mover relative to <em>average-plus</em> price rule. Collectively, the changes sharpen price signals for farm milk while supporting conditions associated with orderly marketing.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 586-589"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859699","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":"Validation of a national genetic evaluation for methane emission in Holstein cattle","authors":"Saranya G. Narayana,&nbsp;Francesca Malchiodi,&nbsp;Allison Fleming,&nbsp;Colin Lynch,&nbsp;Flavio S. Schenkel,&nbsp;Christine F. Baes,&nbsp;Filippo Miglior","doi":"10.3168/jdsc.2026-1010","DOIUrl":"10.3168/jdsc.2026-1010","url":null,"abstract":"<div><div>Lactanet Canada launched a genomic evaluation for methane efficiency for Holsteins in April 2023, utilizing milk mid-infrared–predicted methane (CH₄) emissions (CH_4MIR) as a proxy. This study validated the methane efficiency genomic evaluation using genotyped cows with CH_4MIR and CH₄ records from GreenFeed systems (CH_4GF), along with relative breeding values (RBV) for methane production and methane efficiency from the April 2023 evaluation. In Lactanet's methane efficiency evaluation, a higher RBV indicates more desirable, lower-emitting animals. For the validation, RBV were categorized into quintiles for the CH_4MIR dataset and tertiles for the CH_4GF dataset to evaluate trends across the RBV distribution. Mean CH_4MIR decreased progressively across RBV quintiles for both traits, with all pairwise comparisons among quintiles significantly different. Similarly, CH_4GF emissions declined across RBV tertiles, with significant differences observed between the lowest and highest tertiles. Additional analyses using RBV threshold categories confirmed that cows with the highest RBV consistently exhibited lower methane emissions. Linear regression analyses further demonstrated a negative relationship between RBV and methane emissions, supporting the predictive ability of the genomic evaluation. These findings confirm that Canada's genomic evaluation for methane efficiency effectively differentiates cows by methane emission potential, reinforcing its potential as a tool for genetic selection to reduce methane emissions in dairy cattle.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 608-613"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859120","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":"Inflammation and delayed oral calcium supplementation: Associations with milk yield, reproduction, and herd removal in multiparous Holstein dairy cows","authors":"Kathryn D. Bach,&nbsp;Jackson A. Seminara,&nbsp;Julia Poggi,&nbsp;Jessica A.A. McArt","doi":"10.3168/jdsc.2026-1056","DOIUrl":"10.3168/jdsc.2026-1056","url":null,"abstract":"<div><div>The transition from late gestation to early lactation is characterized by metabolic and immune challenges that predispose dairy cows to conditions such as dyscalcemia and excessive inflammation. Both conditions have been associated with impaired health and productivity, and recent evidence suggests they are physiologically linked. Oral calcium supplementation has been proposed as a strategy to support calcium homeorhesis, but results have been inconsistent, possibly due to cow-level factors such as inflammation. The objective of our observational study was to determine whether inflammatory status at 2 DIM, assessed by serum haptoglobin concentrations, modifies the response to oral calcium supplementation administered at 2 and 3 DIM in multiparous Holstein cows. Serum samples and data from 535 cows enrolled in a previously conducted randomized trial on 4 commercial farms in New York were analyzed. Outcomes included average daily milk yield through 15 wk of lactation, pregnancy to first service, time to pregnancy, and time to herd removal. Linear mixed-effects, quasi-Poisson, and Cox proportional hazards models were used to evaluate associations, with marginal means, risk ratios, and hazard ratios calculated at low (0.4 g/L) and high (1.1 g/L) haptoglobin concentrations. For cows with high haptoglobin concentrations at 2 DIM, oral calcium supplementation increased milk yield by 3.1 kg/d and the risk of pregnancy to first service (risk ratio = 1.6, 95% CI = 0.9 to 2.6) in parity ≥3 cows, and improved the hazard of pregnancy (hazard ratio = 1.3; 95% CI: 1.0 to 1.7) and reduced the hazard of herd removal (hazard ratio = 0.5; 95% CI: 0.3 to 1.0) for cows of all parities. No benefit of oral calcium supplementation was observed in cows with low haptoglobin concentrations at 2 DIM other than a 60% increase in risk of pregnancy to first service for parity 2 cows. Our findings suggest that inflammatory status may modify the response to oral calcium supplementation and highlight the potential for targeted strategies to improve postpartum performance.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"7 5","pages":"Pages 664-669"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148859125","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}