Journal of Dairy Science最新文献

{"title":"Hydrophilic-hydrophobic imbalance is associated with alcohol-positive milk in Holstein cows: An untargeted metabolomics analysis.","authors":"Ri Hu, Dong Luo, Zhanhe Zhang, Qingzhu Sun, Guiying Wang, Donglin Wu, Xiaoping An, Jingwei Qi, Ming Xu","doi":"10.3168/jds.2026-28994","DOIUrl":"https://doi.org/10.3168/jds.2026-28994","url":null,"abstract":"<p><p>Alcohol-positive milk (APM) is a prevalent milk quality defect causing economic losses in dairy production. Using a longitudinal case-control design, this study characterized the metabolomic profile of APM and clarified the core molecular signatures underlying its occurrence in Holstein cows. Twenty milk samples from Holstein cows (10 normal milk [NM] vs. 10 APM) were collected for case-control comparison, and 7 paired samples from spontaneously recovered APM cows (recovered alcohol-negative milk, RAPM) were obtained for longitudinal analysis. Untargeted metabolomic profiling was performed using ultra-high performance liquid chromatography coupled with tandem high-resolution mass spectrometry (UHPLC-HRMS/MS). APM exhibited a distinct bidirectional metabolic dysregulation. On the hydrophilic side, glycolysis/gluconeogenesis and pentose phosphate pathways were inhibited. Key hydrophilic phospholipid precursors (3-phosphoglycerate, 2-phosphoglycerate) were downregulated, impairing de novo synthesis of phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Levels of phosphorylcholine, phosphoethanolamine, and core structural phospholipids (e.g., PC(18:2/0:0), PE(18:2/0:0)) were all reduced. On the hydrophobic side, highly hydrophobic long-chain fatty acid derivatives (e.g., 9,10-epoxystearic acid) were markedly enriched. Excessive lysophosphatidylethanolamine (LPE) also accumulated due to enhanced phospholipid hydrolysis. In conclusion, the bidirectional imbalance between downregulated hydrophilic protective metabolites and upregulated hydrophobic detrimental metabolites is the core metabolic signature of APM. This imbalance disrupts the intrinsic hydrophilic-hydrophobic homeostasis of milk and drives APM occurrence.</p>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149102369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An exploratory dual-platform metabolomics reveals region- and milk source-associated signatures in commercial cheeses.","authors":"Guoxuan Hang, Jiaqi Sun, Lai-Yu Kwok, Guangqi Gao, Weicheng Li","doi":"10.3168/jds.2026-29087","DOIUrl":"https://doi.org/10.3168/jds.2026-29087","url":null,"abstract":"<p><p>Commercial cheeses exhibit distinct compositional profiles shaped by milk substrate, production practices, and geographical terroir. However, the relative contribution of geographic origin versus milk source to cheese metabolomes remains poorly quantified, particularly in unstandardized commercial products. This exploratory study investigated region-associated metabolic signatures in commercially available cheeses, with a focus on comparing the relative contributions of geographic origin and milk source to metabolomic variance. We applied complementary volatile (HS-SPME-GC-MS) and non-volatile (UHPLC-MS/MS) metabolomic profiling to 32 commercial cheeses from Hungary (n = 11) and 3 Australian regions (Queensland, New South Wales, Victoria; n = 21), representing cow (n = 24) and goat/sheep (n = 8) milk sources. Multivariate ANOVA and random forest analyses revealed pronounced metabolic separation by geographic origin, which accounted for a substantially larger proportion of variance than milk source. Hungarian cheeses were enriched in citrate-derived flavor compounds (e.g., 2,3-butanedione, 2,3-butanediol), while Australian samples exhibited elevated lipid oxidation and branched-chain amino acid catabolites. Non-volatile profiles further highlighted regional differences in fatty acid composition and dipeptide abundance, with phenylalanine metabolism emerging as a consistent discriminant pathway. Correlation-based association networks revealed interconnected volatile and non-volatile metabolic modules. Since cheese variety, ripening protocols, and starter cultures were uncontrolled, observed patterns reflect region-associated metabolic signatures rather than causal terroir effects. These findings provide a preliminary metabolomic landscape for authenticity tracing and hypothesis-driven fermentation research. Future controlled trials integrating metagenomics and standardized production parameters are needed to isolate the specific contributions of geography, milk substrate, and processing technology.</p>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149072997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cholesterol and lipid metabolism at the start of lactation in dairy cows with different body condition scores.","authors":"Tobias Heiri, Julia Eichinger, Jonas Hendricks, Anna-Maria Reiche, Frigga Dohme-Meier, Josef J Gross","doi":"10.3168/jds.2026-28641","DOIUrl":"https://doi.org/10.3168/jds.2026-28641","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Over-conditioned dairy cows at calving and those experiencing an energy deficit in early lactation are predisposed to postpartum (p.p.) metabolic disorders such as ketosis and fatty liver disease. While alterations in energy and fatty acid metabolism during early lactation are well documented, short-term dynamics of cholesterol and lipoprotein metabolism at the onset of lactation are poorly characterized. In this study, we investigated the short-term dynamics of cholesterol and lipoprotein metabolism during the first wk p.p. in cows with differing BCS at calving and contrasting feed energy supply p.p. On d 42 antepartum, we randomly assigned 24 multiparous Holstein cows to either a high energy feeding regimen (HC; n = 14, 6.5 MJ NEL/kg of DM; parity: 3.6 ± 0.4) or a low energy feeding regimen (LC; n = 10, 5.0 MJ NEL/kg of DM; parity: 3.0 ± 0.4), resulting in 2 groups with higher and lower BCS (HC: 3.69 ± 0.12; LC: 2.68 ± 0.11) at calving. The lower feed energy supply in HC p.p. further intensified the catabolic metabolism, particularly regarding adipose tissue mobilization and hepatic fatty acid influx. We collected daily blood at 2.24 h after calving and from d 2 p.p. until d 7 p.p. between 0530 and 0800 h together with milk samples and recorded performance data continuously. We analyzed metabolite concentrations related to lipid and cholesterol metabolism [nonesterified fatty acids (NEFA), BHB, triglycerides (TG), total cholesterol, and lipoproteins], as well as enzyme activities [gamma-glutamyl transferase (GGT), glutamate dehydrogenase (GLDH)] using enzymatic assays. The HC cows showed similar DMI but increased ECM resulting in a more severe negative energy balance during the first wk p.p. and a more pronounced BW loss (-90 ±  7 kg vs. -70 ±  7 kg) from shortly before until 7 d after calving compared with LC cows. Plasma NEFA, BHB, and TG concentrations were greater in HC compared with LC cows. While total cholesterol and low-density lipoprotein cholesterol (LDL-C) concentrations did not differ between groups, very low-density lipoprotein cholesterol (VLDL-C) concentration was greater and high-density lipoprotein cholesterol (HDL-C) concentration tended to be greater in HC cows compared with LC cows. Our findings indicate that elevated BCS at calving together with lower feed energy supply p.p. intensifies the catabolic state during early lactation, resulting in greater adipose tissue mobilization and hepatic lipid influx. This metabolic state was associated with altered lipoprotein distribution during the first wk p.p., characterized by changes in lipoprotein-associated cholesterol concentrations and enhanced VLDL-associated lipid. Thus, elevated body condition at calving together with lower feed energy supply p.p. not only exacerbated adipose tissue mobilization p.p. but also induced adjustments in cholesterol metabolism, identifying BCS at calving and the extent of feed energy supply p.p. as a key determinant of hepatic lipid handling","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of 3-NOP on feeding behavior of dairy cows fed maize silage-based diets.","authors":"A J Schwanke, G A Franchi, M Johansen, P Lund, M Maigaard, T J DeVries, M R Weisbjerg, M Bak Jensen","doi":"10.3168/jds.2026-28759","DOIUrl":"https://doi.org/10.3168/jds.2026-28759","url":null,"abstract":"<p><p>The primary objective of this study was to determine the effects of 3-nitrooxypropanol (3-NOP) supplementation and silage source on feed intake and eating behavior in dairy cows fed maize silage-based diets. A secondary objective was to investigate if any observed effects were consistent across silage source, exposure period, parity, and lactation stage. Forty-eight Holstein cows (balanced for multiparous vs primiparous and earlier vs later lactation) were enrolled in a balanced 4 × 4 Latin square design. The dietary treatments consisted of no inclusion or inclusion of 3-NOP (Control: 0 mg; or 3-NOP: 60 mg of 3-NOP/kg of DM), combined with 2 different sources of maize silage (high stubble or low stubble), which were arranged in a 2 × 2 factorial design. The diets were delivered as a partial mixed ration (PMR), in addition to a maximum of 0.81 kg DM/d of concentrate feed in a methane measuring unit (MMU). The entire experiment had 4 periods, each lasting 3 wk. Differences in PMR and total DMI between Control and 3-NOP were dependent on experimental period or week. Cows on 3-NOP spent less time eating PMR (158 vs 187 min/d; SEM = 5.59), made more attempts to access unassigned feed bins (32.5 vs 10.6 visits/d; CI = 19.3 - 54.7 and 6.11 - 18.5 respectively), and more unrewarded visits to the MMU concentrate feeder (2.16 vs 1.54 visits/d; CI = 1.73 - 2.68 and 1.21 - 1.95 respectively). Meal size and meal length were also lesser overall when cows were fed 3-NOP compared with Control (2.44 vs 3.06 kg DM/meal; SEM = 0.08 and 24.7 vs 30.3 min/meal; SEM = 1.03, respectively), with the differences being dependent on experimental week. When cows were fed the high-stubble silage, they had a longer meal criterion if they were also fed 3-NOP compared with Control (32.9 vs 30.8 min; SEM = 1.47). In conclusion, 3-NOP supplementation reduced feed intake, meal length, and meal size, and increased attempts to access alternative sources of feed. However, these effects were not more acute during initial exposure than in the remaining period of exposure. In maize silage-based diets, reduced feed intake in cows fed 3-NOP may indicate alterations in feeding motivation and rumen dynamics, but the mechanisms causing these changes and their potential effects on welfare require further study.</p>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A boronate affinity-assisted molecularly imprinted electrochemical sensor based on Ti₃C₂@AuNPs nanocomposites for the detection of IgG in dairy products.","authors":"Ruyue Zhang, Xuan Liu, Bini Wang, Fuxin Zhang, Yufang Liu","doi":"10.3168/jds.2026-29029","DOIUrl":"https://doi.org/10.3168/jds.2026-29029","url":null,"abstract":"<p><p>Immunoglobulin G (IgG), a critical immunologically active protein with oral bioavailability, has garnered significant attention as a functional nutrient in the food industry. However, its structural complexity and susceptibility to matrix interference in dairy products pose substantial challenges for rapid and reliable detection. In this study, we developed a novel boronate affinity-assisted molecularly imprinted polymer (MIP) electrochemical sensor by integrating Ti₃C₂ MXene with gold nanoparticles (Ti₃C₂@AuNPs) to enable specific, sensitive, and rapid IgG detection. The incorporation of Ti₃C₂@AuNPs enhanced both the specific surface area and electrical conductivity of the electrode interface, while the boronate affinity-assisted imprinting process generated recognition cavities precisely tailored to the target IgG in terms of size, shape, and chemical functionality, thereby significantly improving sensor sensitivity and selectivity. Comprehensive characterization techniques were employed to validate the structural integrity and electrochemical advantages of the nanocomposite. The optimized sensor exhibited a broad linear detection range (3.2-500 ng/mL, R² = 0.994), an ultralow limit of detection (LOD = 3.2 ng/mL), and enabled accurate quantification of IgG in complex dairy matrices. This work presents a generalizable strategy for the development of next-generation biosensors targeting structurally complex nutrients in functional foods.</p>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Invited review: Theoretical concepts and practical applications of the APY algorithm for large-scale genomic evaluations.","authors":"Mohammad Ali Nilforooshan, Jorge Hidalgo, Ivan Pocrnic","doi":"10.3168/jds.2026-29023","DOIUrl":"https://doi.org/10.3168/jds.2026-29023","url":null,"abstract":"&lt;p&gt;&lt;p&gt;The increasing availability of genomic data has transformed modern genetic evaluation systems but has also introduced substantial computational challenges, particularly associated with the inversion of large genomic relationship matrices (G). In genomic best linear unbiased prediction (GBLUP) and single-step GBLUP (ssGBLUP), direct inversion of the G matrix becomes computationally infeasible beyond a threshold in the number of genotypes. Furthermore, G becomes numerically positive semidefinite or singular as the number of genotyped individuals approaches or exceeds the number of markers. The Algorithm for Proven and Young (APY) was developed to overcome this limitation and has since become a cornerstone of large-scale genomic evaluations. Alternative methods to APY exist, which do not require the inversion of G. Currently, applying these methods is relatively straightforward, but this was not the case in the past due to the lack of available software, high computational costs, and convergence issues. The structural similarity between ssGBLUP and BLUP made implementing APY easier than its counterparts. Those alternatives are presented in this review. This study provides a comprehensive synthesis of the theoretical foundations, methodological developments, and practical applications of APY. We present APY as a structured approximation of the inverse of a symmetric matrix with limited effective dimensionality, grounded in the biological properties of genomic data, including linkage disequilibrium, finite effective population size and independent chromosome segments. By conditioning the genomic information of a large set of non-core individuals on a smaller set of core individuals, APY yields a sparse approximate inverse of G, in which non-core individuals are conditionally independent given the core group. This formulation dramatically reduces computational and memory requirements while maintaining prediction accuracy when the core group adequately captures the dimensionality of genomic information. The review highlights that the most critical factors governing APY performance are the size and composition of the core group. Empirical and theoretical evidence shows that an optimal core size corresponds to the effective dimensionality of G, typically assessed via eigenvalue or singular value decomposition. Once this threshold is reached, further increases in core size offer negligible gains in accuracy. In single-breed populations, core composition becomes largely irrelevant beyond the optimal size, whereas in multi-breed and crossbred populations, careful core definition is required to ensure balanced representation and stable evaluations. Beyond its original role in GBLUP and ssGBLUP, APY is discussed as part of a broader class of approximate inverse and dimensionality-reduction methods, with conceptual links to eigenvalue truncation, reduced-rank models, and sparse Gaussian process approximations. The algorithm's applicability extends to alte","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating transfer learning strategies for improving dairy cattle body weight prediction in a small farm using depth-image and point-cloud data.","authors":"Jin Wang, Angelo De Castro, Yuxi Zhang, Lucas Basolli Borsatto, Yuechen Guo, Victoria Bastos Primo, Ana Beatriz Montevecchio Bernardino, Gota Morota, Ricardo C Chebel, Haipeng Yu","doi":"10.3168/jds.2026-28238","DOIUrl":"https://doi.org/10.3168/jds.2026-28238","url":null,"abstract":"<p><p>Computer vision-based approaches have emerged as automated, non-invasive, and scalable tools for monitoring dairy cattle, thereby supporting effective management, health assessment, and productivity. Although transfer learning is commonly employed in studies predicting body weight from images, its effectiveness and optimal fine-tuning strategies remain poorly understood in livestock applications, particularly beyond the straightforward use of pretrained ImageNet or Common Objects in Context weights. In addition, while both depth images and 3-dimensional point-cloud data have been explored for body weight prediction, direct, head-to-head comparisons of these 2 modalities in dairy cattle are limited. Therefore, the objectives of this study were to 1) evaluate whether transfer learning from a large farm can enhance body weight prediction performance on a small farm with limited data, and 2) compare the predictive performance of depth-image- and point-cloud-based approaches under 3 experimental designs. Top-view depth images and point-cloud data were collected from 1,201, 215, and 58 cows at large, medium, and small dairy farms, respectively. Four deep learning models were evaluated: ConvNeXt and MobileViT for depth images, and PointNet and DGCNN for point clouds. We found that transfer learning consistently improved body weight prediction on the small-farm test set compared with single-source learning and achieved performance comparable to, or greater than, that obtained through joint learning. These results indicate that pretrained representations can generalize effectively across farms with differing imaging conditions and dairy cattle populations. No consistent performance difference was observed between depth-image- and point-cloud-based modeling pipelines under the data acquisition and processing conditions evaluated in this study. Taken together, our findings suggest that transfer learning provides a practical alternative to cross-farm data sharing for small-farm prediction scenarios, where direct sharing of raw data may be constrained by logistical, data-governance, or policy considerations, as it requires access only to pretrained model weights rather than raw data.</p>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of salt (NaCl) drinking water on physiological and productivity responses of dairy cattle.","authors":"L Managos, S Agenäs, M Åkerlind, P P Nielsen, K Dahlborn, A Jansson","doi":"10.3168/jds.2026-28424","DOIUrl":"https://doi.org/10.3168/jds.2026-28424","url":null,"abstract":"<p><p>Climate change is increasing the risk of freshwater scarcity in dairy production, highlighting the need to evaluate alternative water sources. This study investigated the physiological and production responses of dairy cows offered drinking water with salinity comparable to that of the brackish Baltic Sea (salinity 0.2 - 0.9%). First, a pilot study was conducted to assess acute responses (48 h) to a near-isotonic solution (0.8% NaCl, i.e., 8 g NaCl/kg) and to inform sampling times for the main study. In the main study, 18 multiparous cows (208 ± 22 d in milk, 35.5 ± 4.7 kg milk yield/d) were assigned to 3 drinking water treatments in a breed-stratified, 3-period crossover design using a replicated 3 × 3 Latin-square treatment allocation: fresh water, medium salinity (4 g NaCl/kg), and high salinity (8 g NaCl/kg). Cows were allocated to one of 3 treatment sequences, ensuring that each cow received all treatments over 3 consecutive 14-d periods. Blood, urine, and fecal samples were collected at 14 h, 22 h, and 14 d in each treatment, and data were analyzed using linear mixed-effects models. Plasma osmolality increased, and total plasma protein concentration decreased within 14 h following exposure to salt water but returned to levels observed in the freshwater treatment after adaptation. Water salinity did not affect milk yield, energy-corrected milk yield, milk osmolality, fat and protein concentrations, or somatic cell count. Fluid intake increased with increased salinity, accompanied by increased urine volume and urinary and fecal sodium concentrations. However, body weight, body condition score, or fecal dry matter remained unaffected. These results indicate that dairy cows can adapt to drinking water with near isotonic NaCl content without compromising production. The results are promising with respect to the potential use of brackish water as an alternative during periods of freshwater scarcity.</p>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repeated inflammatory challenges alter inflammatory and metabolic responses in lactating dairy cows under negative energy balance.","authors":"Miguel Chirivi, Ursula Abou-Rjeileh, Madison N Myers, Jair Parales-Girón, Jose M Dos Santos Neto, Lynn C Worden, Adam L Lock, G Andres Contreras","doi":"10.3168/jds.2026-28993","DOIUrl":"https://doi.org/10.3168/jds.2026-28993","url":null,"abstract":"<p><p>During the periparturient period, dairy cows enter a state of negative energy balance (NEB), a metabolic state characterized by increased lipid mobilization and physiological adaptations. Additionally, this period is frequently accompanied by inflammatory and endotoxemic insults associated with common periparturient disorders. Importantly, cows affected by an adverse health event during the first weeks of lactation face increased odds of developing a second disease within weeks of the first, compounding the risk of morbidity, mortality, and early removal from the herd. While the metabolic effects of NEB are well recognized, the impact of repeated inflammatory challenges during this state remains poorly understood. The objective of this study was to characterize the metabolic and inflammatory responses of dairy cows in NEB to a repeated endotoxemic challenge. Thirty-two multiparous mid-lactation Holstein cows underwent a 4-period experimental protocol. During Period 0 (P0; 0-7 d), baseline data were collected under ad libitum feeding. In Period 1 (P1; 8-11 d), cows were subjected to feed restriction to induce NEB (-14 Mcal/d), and on d 10, cows received an i.v. infusion of either sterile saline (SAL; n = 16) or LPS (1 µg/kg BW; n = 16). A recovery period (REC; 12-18 d) served as a washout with ad libitum feeding. In Period 2 (P2; 19-22 d), the feed restriction protocol was repeated, and cows were assigned within their original groups to receive a second infusion of SAL or LPS on d 21, resulting in 4 treatment groups: S-SAL, S-LPS, L-SAL, and L-LPS (n = 8 per group). Feed restriction reduced milk yield, plasma glucose, and BHB, while increasing plasma NEFA. During P1, LPS reduce BHB compared with SAL. LPS also increased body temperature (+1.0°C over baseline in the first 6 h), circulating cytokines, and acute-phase proteins. In addition, LPS induced metabolic acidosis and hypocalcemia compared with SAL. During P2, L-LPS showed higher body temperature than S-LPS (+1.82 vs. +1.0°C, over baseline at 6 h post-infusion, respectively). Compared with S-LPS, L-LPS elicited a greater increase in heart rate. Furthermore, L-LPS induced an earlier increase and faster resolution of lipopolysaccharide-binding protein compared with S-LPS, while the haptoglobin response was attenuated by 31% in L-LPS. Additionally, S-LPS displayed lower concentrations of IP-10, MCP-1, and MIP-1β compared with L-LPS. Hypocalcemia and acidosis were milder in L-LPS compared with S-LPS. Together, these findings indicate that in the context of NEB, repeated endotoxemic events in dairy cows induce an altered inflammatory and metabolic phenotype characterized by selective immune training and attenuated metabolic disturbances, which may contribute to altered disease susceptibility during early lactation.</p>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of colostrum supplementation administered at a behavior-based alert for calf diarrhea.","authors":"A Welk, M C Cantor, M B Jensen, C B Winder, D L Renaud","doi":"10.3168/jds.2026-28833","DOIUrl":"https://doi.org/10.3168/jds.2026-28833","url":null,"abstract":"&lt;p&gt;&lt;p&gt;The objective of this randomized clinical trial was to determine whether supplementing colostrum at the time of a behavior-based alert would reduce diarrhea severity and improve feeding behavior, activity, and growth in Holstein calves. Calves were trained to use an automated milk feeder (Foerster-Technik) at 3 d of age and offered milk replacer ad libitum until 4 wk, 9 L/d from 4 to 7 wk, and gradually weaned from 7 to 9 wk. Calf starter (20% CP) was offered ad libitum from 3 d of age via a separate automated feeder. A behavioral alert (≤60% rolling deviation in milk intake or drinking speed over 2 d) identified calves at risk for diarrhea between 3 to 21 d of age. A total of 179 calves were monitored; however, only 88 calves created an alert. Calves were randomly assigned to receive 1 L of bovine colostrum replacer (CR; 130 g/L, 14% IgG, 46% CP, 25% CF, 5.37 Mcal/kg) or 1 L of milk replacer (MR; 150 g/L, 26% CP, 18% CF, 4.53 Mcal/kg) once daily for 4 d by bottle. Fecal consistency was scored daily until 14 d post-alert; diarrhea was defined as loose feces for ≥ 2 d or watery feces for ≥ 1 d. Calves were enrolled at their first alert and remained in the analysis regardless of diarrhea status. Body weight was recorded at birth, at alert, and weekly thereafter, and activity was measured using accelerometers from 3 d of age. Mixed Poisson regression assessed diarrhea duration, and mixed logistic regression evaluated the odds of receiving supportive treatments administered by farm staff blinded to treatment assignment (non-steroidal anti-inflammatory drugs (NSAID) and additional milk supplementation). Mixed linear regression models with repeated measures evaluated milk intake, drinking speed, steps, growth, and the treatment × time interaction over 14 d and 6 wk post-alert. Calves triggered the alert at 10.3 ± 2.7 d of age and were diagnosed with diarrhea at 10.2 ± 2.6 d. Diarrhea duration did not differ between treatments (incidence rate ratio = 1.11; 95% CI: 0.86-1.43). However, CR calves had lower odds of receiving an NSAID (OR = 0.10; 95% CI: 0.02-0.45) and milk supplementation (OR = 0.26; 95% CI: 0.09-0.80) than MR calves 14 d post-alert. Over the 14 d post-alert, CR calves consumed more milk (9.3 ± 0.23 vs. 8.4 ± 0.21 L/d) and had faster drinking speeds (435 ± 11 vs. 399 ± 11 mL/min). A day × treatment interaction was observed for steps, with CR calves performing 180 ± 76 more steps/d from d 8-13. Over 6 wk, CR calves had greater starter intake (191; 95% CI: 142-246 vs. 153; 95% CI: 110-205 g/d), and a treatment × week interaction for body weight, resulting in a 2.0 ± 0.79 kg advantage from 2 to 6 wk post-alert. Short-term colostrum supplementation at the time of a behavior-based alert did not reduce diarrhea duration but reduced the need for additional treatments and improved feeding behavior, activity, and growth. These findings suggest that colostrum supplementation following a behavior-based alert may support recovery and longer-term","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":" ","pages":""},"PeriodicalIF":4.7,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}