Search Results (213)

Sustainable cow–calf production requires balancing animal performance, economic returns, and environmental impacts under highly variable forage conditions. This study presents a conceptual model, CattleSat, whose decision-support framework integrates satellite-derived forage biomass with mechanistic ruminant nutrition models to simulate the effects of herd size and stocking strategies on animal performance, greenhouse gas emissions, and economic outcomes. A case study simulation using data from a Texas grazing system was conducted to demonstrate the application and behavior of the model under variable herd sizes. Results showed that increasing herd size reduced forage allowance, leading to decreased cow dry matter intake and, consequently, individual animal performance, particularly milk yield and weaning weight, while total calf production exhibited a curvilinear response. Economic outcomes followed similar patterns, with total net return increasing but net return per cow declining as herd size increased. Based on the assumptions and parameterization adopted in this simulation, a critical transition point was identified where system-level profitability and individual efficiency were balanced. Additionally, carbon emission intensity increased at higher stocking rates, indicating reduced environmental efficiency. Overall, forage dynamics were relevant drivers of system variability. These findings highlight the importance of adaptive, data-driven stocking strategies and demonstrate the potential of integrating remote sensing with mechanistic models to improve the sustainability of grazing systems. Future studies and model improvements should be incorporated to expand the applicability of the framework across diverse grazing systems. Full article

Background: The translocation of diet-derived antigens from the maternal intestine to breast milk represents a primary gateway for neonatal immune priming, yet the structural basis for why certain proteins survive this transit while others do not remains poorly understood. This review introduces the “Survivor Peptide” hypothesis, proposing that specific food allergens possess intrinsic “stability architectures” that enable them to resist maternal digestion and navigate the gut–mammary axis to reach the infant in an immunologically active form. Methods: We analyzed the current literature regarding the detection and structural characteristics of food allergens in human milk. Integrating evidence from 26 major sources, we performed an in silico structural analysis of five representative “survivor” proteins: Gal d 1 (egg white), Bos d 5 (cow’s milk), Gal d 6 (egg yolk), Tri a 19 (wheat), and tropomyosin (Der p 10-mite/shellfish). High-resolution 3D models were retrieved from the Protein Data Bank and AlphaFold2, and then visualized in UCSF ChimeraX to map stability anchors, including disulfide bonds and hydrophobic clusters, against solvent-accessible IgE-binding epitopes. Results: We identified and categorized allergens into distinct Molecular Resilience Architectures: the “Covalent Cage” (Gal d 1), defined by dense disulfide stapling, the “Glycoprotein Shield” (Gal d 6), utilizing yolk-matrix structural anchors, the “Topological Shield” (Bos d 5), characterized by a stable β-barrel, and “Coiled-Coil Rigidity” (Der p 10). These frameworks protect large, immunogenic fragments that maintain the spatial arrangement required for IgE cross-linking. Conclusions: Allergen persistence in the gut–mammary axis is dictated by a protein’s intrinsic structural architecture. Identifying these stability fingerprints provides a unified theory for allergen persistence and offers a path for refining component-resolved diagnostics and neonatal oral tolerance strategies. Full article

This study evaluated the implementation of reproductive technologies and their effects on pregnancy rates (PRs) and calving distribution. Producers (n = 11) were enrolled in Level 1 or 2 and subsequently transitioned to Level 2 or 3. Level 1: females were exposed to natural service (NS) only versus estrous synchronization (7d-CIDR) before NS (SynNS). Level 2: SynNS versus fixed-time artificial insemination (SynAI; 7d-CO-Synch + CIDR) with conventional semen. Level 3: conventional versus sex-skewed semen (FTAI-con and FTAI-sexed, respectively). Artificial insemination occurred 60–66 h post CIDR removal (SynAI; FTAI-con; FTAI-sexed) and bulls were introduced on d 0 (NS and SynNS) or 10–14 d post artificial insemination (SynAI; FTAI-con; FTAI-sexed). Breeding season PRs did not differ between treatments (p > 0.50). In Level 2, SynNS had greater 21 d PRs compared to SynAI (p < 0.01). For Level 3, FTAI-con had greater 21 d PRs compared to FTAI-sexed (p < 0.01). In Level 1, the proportion of cows that calved by day 14 was greater for SynNS compared to NS (p < 0.01). In Level 2, SynAI had a greater proportion calved by day 7 (p = 0.01); however, SynNS had a greater proportion calved by day 21 and 42 (p < 0.01). In Level 3, FTAI-con had a greater proportion calved by day 14 and 21 (p < 0.01) compared to FTAI-sexed. In conclusion, reproductive technologies altered the calving distribution with more calves born earlier. Full article

Rumen microbial fermentation plays a central role in nutrient utilization and milk production in dairy cows. This study evaluated the effects of supplementation with exogenous fibrolytic enzymes, alone or in combination with live yeast on rumen microbiota, fermentation characteristics, nitrogen-related metabolites, and production performance during the transition from outdoor grazing to indoor housing. Thirty Lithuanian Red dairy cows were assigned to control (CTR), enzyme (E), or enzyme plus yeast (YE) treatments across outdoor (OD) and transit (T) periods, while nine cows (three per group) were selected for rumen and microbiota analysis. Rumen bacterial communities were characterized using 16S rRNA gene sequencing, and functional parameters were evaluated using linear mixed-effects models. Supplementation resulted in selective changes in several bacterial genera, including Blautia spp., WPS-2, Ruminococcus spp., Erysipelotrichaceae UCG-009, Sharpea spp., uncultured Bacteroidales, and Prevotellaceae UCG-003, and was associated with alterations in fermentation patterns, particularly propionate concentration, and in nitrogen metabolism, including putrescine dynamics. The transition period significantly influenced microbial diversity and total bacterial abundance across treatments. Cows in the YE group maintained higher milk yield during the transition period. Overall, dietary supplementation modulated specific rumen metabolic responses and contributed to production stability without causing large-scale changes in overall microbial structure. Full article

The responsiveness of the stress axis is fundamental for maintaining health and sustaining productive performance; however, the effect of modulating this stress axis with bovine appeasing substance and its effects on biochemical, immunological, oxidative parameters and uterine involution have not been determined, which are the objectives of this experiment. To elucidate these questions, Holstein cows, from the prepartum to lactation period in a cross-ventilation system, received an application of a bovine appeasing substance (treated group) and a 0.9% saline solution (control group) at the time of calving, and blood samples were collected on calving day and on days 3, 7, 14 and 21 postpartum for analysis. Modulation of the stress axis by bovine appeasing substance increased magnesium levels on days 7 and 14 postpartum, with a reduction in fructosamine levels on days 3, 7, 14, and 21 postpartum. A reduction in ferritin levels, an acute-phase protein, and a reduction in interleukin 1 beta and interleukin 6 were also observed, demonstrating an anti-inflammatory effect in cows of the treated group. Creatine kinase activity decreased on day 21 postpartum in cows treated with bovine appeasing substances. An increase in cholinesterase activity on day 7 and a marked decrease on day 21 postpartum in treated cows were observed compared to the control. This was accompanied by a reduction in beta-hydroxybutyrate levels on day 7 and a reduction in reactive oxygen species levels on day 14 in animals of the treated group, indicating modulation of ketogenesis and reduced oxidation through an anti-inflammatory effect. Mean uterine thickness was also affected by the bovine appeasing substance, with a lower mean thickness on day 21 postpartum in treated cows. Modulation of the stress axis by the bovine appeasing substance reduces inflammation, improving energy dynamics and reducing oxidation, thus facilitating tissue repair associated with postpartum uterine involution in dairy cows. Full article

Ketosis is a major metabolic disorder that significantly impacts dairy cow health, welfare, and farm profitability, posing challenges to both farmers and veterinarians. This opinion paper, derived from expert panel discussions and a review of the scientific literature, provides a comprehensive, proactive approach to modern ketosis management. It addresses the critical need for increased farmer awareness, emphasizing the veterinarians’ involvement as consultants and data interpreters and equipping them with essential skills in data analysis, communication, and farmer education. This paper also details a practical toolbox of diagnostic, therapeutic, management, and preventive strategies, including precision technologies and welfare-enhancing practices, to optimize metabolic health, enhance productivity, and ensure the long-term sustainability of dairy farming. This expert consensus translates scientific knowledge into practical on-farm actions, empowering farmers with risk-based insights and equipping veterinarians with tools and strategies for success. Ultimately, the consensus of our opinion paper reflects an industry-wide transition toward absolute transparency in diagnostic reporting, based on reliable data that creates an indispensable foundation for evidence-based ketosis management. Full article

Resveratrol (RES) has been shown to exhibit therapeutic efficacy against fatty liver disease. Yet, the molecular mechanisms by which RES ameliorates liver injury remain unclear. The aim of this study was to investigate the therapeutic effect and mechanism of resveratrol in fatty liver disease. It was found that dairy cows with fatty liver exhibit characteristic hepatic pathologies, including ballooning degeneration, lipid accumulation and elevated serum AST and ALT levels. Parallel to these changes, we observed significant upregulation of the NLRP3 inflammasome alongside suppression of mitophagy in the liver. Additionally, it was demonstrated in vitro that resveratrol pretreatment effectively alleviated PA-triggered NLRP3 inflammasome activation and mitochondrial dysfunction. Furthermore, RES’s mitigating effects against NLRP3 inflammation and mitochondrial injury were reversed by suppressing PINK1-medicated mitophagy. In vivo experiments further demonstrated that resveratrol administration attenuated HFD-induced liver injury and lipid accumulation in a mouse model, concurrent with suppressed NLRP3 activation and an increase in mitophagy, further confirming the mechanism identified in vitro. Our findings reveal that RES ameliorates fatty liver injury primarily by inhibiting the NLRP3 inflammasome through PINK1-mediated mitophagy, which provides a potential novel therapeutic strategy for mitigating fatty liver disease. Full article

Retained placenta (RP) is a significant postpartum complication in dairy cows. Although abnormal estradiol (E₂) levels are implicated, the underlying cellular mechanisms remain poorly defined. Through RNA-seq analysis of postpartum blood from cows with or without RP, we identified Serum and Glucocorticoid-regulated Kinase 1 (SGK1) as a differentially expressed gene candidate. Analysis of fetal cotyledonary tissues revealed that SGK1 expression was significantly elevated in these tissues, concomitant with markers of suppressed apoptosis, increased levels of tight junction proteins, and an inhibited epithelial–mesenchymal transition (EMT) phenotype. To explore a potential mechanistic link between E₂ and these cellular alterations, we investigated the E₂-SGK1 axis in bovine endometrial epithelial cells in vitro. E₂ treatment upregulated SGK1 expression, reduced apoptosis, increased tight junction protein levels, and suppressed EMT. Conversely, SGK1 knockdown induced apoptosis, disrupted tight junctions, and impaired EMT. Notably, E₂ could not rescue the apoptosis and EMT alterations in SGK1-knockdown cells, indicating that SGK1 is a critical mediator of these E₂ effects in this cellular model. Based on these initial correlative findings in tissues, combined with the subsequent mechanistic experiments in cells, we propose a novel model whereby dysregulation of the E₂- SGK1 axis could contribute to RP pathogenesis by stabilizing the placental interface. Our findings provide the first experimental evidence linking SGK1 to RP and establish a foundation for future in vivo validation. Full article

The transition period in dairy cows is marked by metabolic, oxidative, and immune challenges that increase susceptibility to periparturient diseases. Injectable mineral supplementation (IMS) has been proposed to support immunometabolic adaptation by enhancing antioxidant capacity and immune function, with consistent associations with improved health outcomes but variable effects on production. Therefore, this study evaluated the effects of repeated intramuscular multi-mineral supplementation during the transition period on health, metabolic stress, immune status, and productive performance in Holstein cows. Supplementation was associated with lower odds of subclinical hypocalcemia on day 4 postpartum in primiparous cows (p = 0.02) and overall for persistent subclinical hypocalcemia (p = 0.03). Multiparous cows (p = 0.04) and the overall population (p = 0.01) showed consistent effects on metritis following IMS. Supplemented cows had improved metabolic and uterine health indicators without affecting energy metabolism-related disorders. Although no differences were detected for major postpartum health disorders, its main benefits may involve immune competence, oxidative regulation, and physiological resilience rather than energy balance. Full article

Dairy cows commonly experience negative energy balance during the periparturient period, predisposing them to metabolic disorders such as ketosis (KET), hypophosphatemia (HP), hypocalcemia (HC), and hypomagnesemia (HM). However, comparative data on breed- and parity-related differences remain limited. Therefore, these differences were evaluated in this study during the postpartal transition period. A total of 174 cows (149 Holstein, 25 Jersey) were monitored, and blood samples were collected from calving to 21 days postpartum at 3-day intervals to measure β-hydroxybutyrate, inorganic phosphorus, calcium, and magnesium concentrations. Metabolic disorders were defined using established thresholds. Data were analyzed using Fisher’s exact test, the Mann–Whitney U test, and generalized estimating equations. HP was the most prevalent disorder in both breeds. Jerseys had 2.83 times higher odds of KET, whereas Holsteins had 4.98 times higher odds and an earlier onset of HM. Multiparous Holsteins showed higher incidences of HP, HC, and HM compared to primiparous ones, while parity effects were minimal in Jerseys. Breed and parity significantly influenced both the incidence and onset timing of postpartal metabolic disorders. These findings highlight the importance of breed- and parity-specific health management strategies in dairy cattle farms. Full article

The transition period in dairy cows involves profound metabolic adaptations that challenge energy balance and liver function. This study evaluated the effects of rumen-protected methionine (RPM) and choline (RPC) on hepatic and skeletal muscle metabolism. Twenty-one multiparous Holstein cows from a 2 × 2 factorial design (CON, RPM, RPC) underwent liver and semitendinosus biopsies at −10, +7, and +20 d relative to parturition. Untargeted LC-MS metabolomics detected 2288 and 1454 molecular features in liver and muscle. Data were analyzed using mixed-model ANOVA (FDR ≤ 0.05), complemented by multivariate approaches including sparse PLS-DA and PERMANOVA to assess global metabolic variation. Metabolite annotation was performed using HMDB (±0.005 Da). Dietary supplementation significantly affected 105 hepatic metabolites, whereas time influenced 552 metabolites, generally reflecting increases or decreases in concentration from the prepartum to early postpartum periods. Network analysis identified nine hepatic co-expression modules associated with RPM and RPC. Hub metabolites included glucose-6-phosphate, mannose-6-phosphate, and sphingomyelins, indicating modulation of carbohydrate and lipid metabolism. In muscle, treatment effects were modest, with PERMANOVA and PLS-DA confirming limited discrimination among groups and a predominant temporal effect. Overall, RPM and, to a lesser extent, RPC modulated key hepatic metabolic pathways, supporting energy and redox homeostasis during early lactation. These findings highlight the potential of methyl-donor supplementation to enhance metabolic resilience at the tissue level in transition cows. Full article

This study evaluated the effects of dietary Myrtus communis L. extract on the production performance, immune functions, and metabolic and health status of Holstein cows throughout the transition period. Forty cows were assigned to either a control group (n = 20) or a treatment group (n = 20) receiving Myrtus communis L. extract at 1.5 mL/kg body weight per day. Milk yield and feed intake were recorded daily, whereas blood samples were collected weekly. Reproductive performance and health status were monitored. Myrtus communis L. supplementation increased dry matter intake during prepartum and early and mid-lactation and elevated prepartum glucose levels. Treated cows produced more milk in early (44.56 vs. 40.72 kg/day) (p < 0.0001), and mid-to-late lactation (42.57 vs. 37.19 kg/day) (p < 0.0001). NEFA and BHBA concentrations were lower in the treatment group (p = 0.015 and 0.019, respectively), whereas cortisol and ALT were higher around calving (p < 0.001). Despite similar prepartum inflammatory profiles, treated cows demonstrated higher TNF-α concentrations at calving (p = 0.006). The days open and insemination number per pregnancy did not differ; however, the number of ovarian cysts were less in treated cows. Overall, Myrtus communis L. extract offered at a dose of 1.5 mL/kg body weight during the transition period improved feed intake, enhanced milk production, and reduced metabolic stress, suggesting its potential as a natural additive to support energy balance and reproductive performance in cows. However, it increased the blood cortisol and ALT concentrations, which requires further investigation. Full article

Conjugated linoleic acid (CLA) is produced by bacterial biohydrogenation in the rumen of cattle, fulfills various biological functions, and is known for anti-obesity, anti-inflammation, anti-cancer, and other beneficial effects. It has numerous isomers, of which cis-9,trans-11 CLA accounts for 80% of total CLA, followed by trans-10,cis-12 CLA (t10,c12 CLA), with distinct molecular structures, oxidation efficiencies, activities, and functions. Different effects were observed, when isomers were individually supplemented in livestock nutrition. Currently, CLA is supplemented into the diets of dairy cows to improve the energy balance, and avoid negative effects of energy loss during the transition period. Furthermore, t10,c12 CLA was shown to reduce subcutaneous fat and to improve intramuscular fat (IMF) content in the carcasses of ruminants and pigs. Increasing the IMF content without increasing other fat depots and without compromising feed efficiency is an important goal in beef production. However, inconsistent and conflicting results were reported partly based on different study designs. This review aims to summarize studies on CLA supplementation in cattle, focusing on t10,c12 CLA and the effects of the dose, time, and method of supplementation on energy balance, milk yield and body composition, as well as on individual cells in vitro. This may improve our understanding of energy-saving and repartitioning effects of CLA in cattle. Full article

The transition period, spanning approximately three weeks before and after parturition, represents one of the most critical physiological windows in dairy production. Profound metabolic, endocrine, and immune adaptations occur as the cow shifts from gestation to lactation, predisposing high-yielding cows to oxidative stress, inflammation, and metabolic imbalance. Negative energy and metabolisable protein balances stimulate extensive lipolysis and the accumulation of non-esterified fatty acids (NEFAs) and β-hydroxybutyrate (BHBA), which can impair hepatic function and postpartum performance. This review integrates recent advances in the understanding of metabolic and immunometabolic regulation during transition, emphasising the interplay among energy metabolism, oxidative stress, and immune dysregulation. It critically re-evaluates current nutritional interventions including controlled-energy and negative DCAD diets, rumen-protected polyunsaturated fatty acids, and methyl donor amino acids while highlighting the emerging potential of injectable trace minerals as adjunct strategies to improve metabolic resilience. The review concludes by outlining remaining knowledge gaps and proposing a framework linking physiological mechanisms with targeted nutritional management. Full article

Background: Negative energy balance (NEB) during the transition period is associated with profound changes in the body condition and metabolic dynamics of dairy cows. However, the detailed lipidomic changes in milk induced by NEB are unclear, and lipid biomarkers that indicate the energy status of cows remain to be established. Methods: Using a combination of GC-FID, HILIC-MS and RP-LC-MS, we performed a systematic comparison of lipid composition between early lactating (DIM: 5–14) and mid-lactating (DIM: 65–80) milk. Results: We found that NEB in cows caused a profound modification in the profile of all the lipid classes surveyed, including phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI), sphingomyelin (SM), lysophosphatidylcholine (LPC), PC-plasmalogen (PCP), PE-plasmalogen (PEP), lactosylceramide (LacCer), acylcarnitine (AcylCar) and triglycerides (TAGs). Except for LPC and AcylCar, which were reduced and increased, respectively, by NEB, the responses of other lipid classes varied across different species. For phospholipids and TAGs, species containing de novo FAs (C4:0–C16:0) and odd-chain FAs (C15:0 and C17:0) were markedly downregulated, whereas those comprising long-chain preformed FAs were upregulated by NEB. Conclusions: Comprehensive lipidomic profiling of early and mid-lactating milk from two large cohorts of cows allowed us to identify nine lipids (PE 33:1, LacCer 32:1, LacCer 39:1, LacCer 41:1, SM 36:1, SM 36:2, SM 37:1, PEP 38:4 and PEP 38:5) as potential biomarkers of NEB in dairy cows. Full article