Search Results (347)

A cross-sectional study was carried out on small-scale dairy farms in Paraíba State, Brazil, to evaluate the prevalence and anatomical distribution of integument injuries in grazing dairy cows. Twelve herds (n = 12) were assessed, recording herd size, milk yield, and daily hours of pasture access. The integument of five body regions (back/shoulder/neck, carpus, flank/side/udder, tarsus, and hindquarters) was scored for hairless spots, lesions, and swellings (0 = absent; 1 = present). Among 335 cows observed, 267 (81.5%) presented at least one injury. The most frequent conditions were hairless patches on the hock (65.4 ± 5.03%), lesions on the flank/side/udder (34.5 ± 1.46%), and swelling in the back/shoulder/neck region (52.9 ± 5.86%). Cluster analysis revealed distinct patterns of integument injuries among cows. The high prevalence of integument injuries indicates that even in grazing systems, welfare concerns persist. Neck swelling and hairless spots on the hock were the most common problems, emphasizing the need for improved management and environmental practices to enhance welfare outcomes. These findings have practical implications for welfare assessment and management strategies in tropical grazing dairy systems. Full article

Infrared thermography has been proposed as a non-invasive tool for mastitis detection in dairy ruminants; however, the extent of environmental confounding and diagnostic performance in small ruminants remain poorly characterized. This study evaluated udder thermography in dairy goats through correlation analysis under winter and summer conditions, and an experimental intramammary inflammation challenge using Staphylococcus aureus lipoteichoic acid, with receiver operating characteristic analysis using somatic cell count >1500 × 10³ cells/mL as the reference standard. Strong positive correlations between ambient temperature and udder surface temperatures intensified substantially from winter to summer, while surface temperatures showed weak or absent correlations with rectal temperature. Experimental inflammation induced a 12-fold increase in somatic cell count (305 vs. 3658 × 10³ cells/mL, p < 0.001); however, thermographic responses remained minimal and spatially inconsistent, with area under the curve values approximating 0.5 and weak correlations between thermographic measurements and somatic cell count. Environmental temperature variation and physiological thermoregulatory adjustments substantially exceeded the minimal thermal signal generated by intramammary inflammation, limiting diagnostic utility. Infrared thermography showed poor diagnostic utility for detecting experimentally induced intramammary inflammation in dairy goats under the tested conditions. Full article

Production diseases in dairy cattle impose economic and welfare burdens, yet few studies quantify costs using on-farm cases. This study aimed to estimate costs and lost revenues at the individual-animal level in 10 German dairy farms (average of 592 cows; 9694 kg marketed milk/cow/year; 32.9% culling rate). Each farm was visited for three weeks; diseased cows and calves were examined by a trained veterinarian. Diagnoses, treatments, labour times, and outcomes were recorded, and costs calculated for labour, products, veterinary and orthopaedic services, discarded milk, decreased milk yield, culling, book loss, and reduced carcass value. In total, 1272 single-animal cases were included: 68% were stand-alone diseases, 11% involved multiple diagnoses within one organ system, and 21% affected several organ systems. When several diseases occurred in the same animal, total costs and lost revenues were greater than the sum of stand-alone cases, indicating compounding effects. High-impact conditions included mastitis, claw disorders, left displaced abomasum, and multimorbidity; per-case losses ranged from €43 (digital dermatitis) to >€1200 (left displaced abomasum with complications). Labour and culling-related costs were higher than reported, and productivity losses exceeded treatment costs in many cases. Findings support farm-level decision-making, prevention, and parameterization of future dynamic models. Full article

The need for new feed ingredients that could reduce methane (CH₄) emissions from dairy cattle while maintaining rumen function is essential for sustainable milk production. This study aimed to evaluate the CH₄ mitigation potential of selected microalgae and macroalgae, along with an agro-industrial by-product, using two feeding strategies, and hypothesized that lipid- and polyphenol-rich materials would reduce CH₄ production in an inclusion-dependent manner. An in vitro batch culture study (24 h) was conducted to evaluate microalgae (Euglena gracilis and Aurantiochytrium spp.), macroalgae (Undaria pinnatifida), and an agro-industrial by-product (grape marc) either as feed additives (5%) or as a partial replacement of the concentrate mixture (30%, 50%, and 70%) in a basal diet consisting of 50% Klein grass hay and 50% concentrate mixture. As a feed additive, grape marc stands out for its potential to reduce CH₄ yield by about 43.3% without adversely affecting digestibility, pH, or total volatile fatty acid concentrations. When used as feed replacements, Euglena-, Aurantiochytrium-, and grape marc-based feeds reduced CH₄ yield at the highest replacement levels (50 and 70%); however, these effects were accompanied by decreased total gas production and volatile fatty acid concentrations, indicating reduced fermentation activity. Meanwhile, at a 30% replacement level, they showed promising efficiency as alternative feeds. Overall, CH₄ mitigation depends more strongly on inclusion strategy rather than feed type. Lipid-rich microalgae showed potential as concentrate replacements up to 30%, whereas grape marc was most effective as a feed additive for reducing CH₄ emissions. Full article

This study evaluated key reproductive and productive parameters of the Romanian buffalo reared under temperate-continental conditions. Data collected over a 30-year period (1990–2020) from 310 female buffaloes raised at the Şercaia Buffalo Research and Development Station (Brașov County, Romania) were analyzed. Only animals that completed their first gestation and calving within the herd and had complete lifetime records were included. Buffaloes were monitored longitudinally from first calving until the end of their productive life, regardless of the reason for exit. The evaluated traits included age at first calving, number of lactations, milk yield, milk fat content, and the effect of calf sex on milk production. Data were analyzed using descriptive statistics, group comparisons, and linear regression. Mean age at first calving was 51.6 ± 14.0 months, and females completed an average of 7.8 ± 3.0 lactations, indicating good reproductive longevity. Buffaloes calving male offspring produced significantly more milk per lactation (1272 ± 267 L) than those calving female offspring (1099 ± 244 L; p < 0.01). Milk fat content averaged approximately 7% and did not differ significantly between females giving birth to female offspring and those giving birth to male offspring (p > 0.05). Overall, the results indicate good productive stability and reproductive durability of the Romanian buffalo under semi-intensive management and confirm its adaptability to temperate environments. Full article

Acid-induced coagulation of milk plays an important role in the production of dairy products with high quality. The gel texture is significantly affected by processing conditions such as heat treatment and mineral composition. This study examines the effect of moderate heat treatment applied at 65 °C for 5 min and ionic calcium supplementation (10 mM CaCl₂) on coagulation at 30 °C for 180 min of cow’s milk induced by glucono-δ-lactone (GDL). A slow and gradual protonation was induced, reaching pH values of 4.3–4.5. Rheological analysis revealed an increase in G′ from 59.28 Pa for raw milk gel to 224.1 Pa after the addition of CaCl₂. An inverse trend was observed for gel produced with heated milk after the addition of CaCl₂. However, the gel produced from calcium-fortified heated milk showed G′ values of 136.7 Pa. Turbiscan analysis showed the highest TSI for gels made from heated milk. Scanning electron microscopy analysis indicates that raw milk gels supplemented with CaCl₂ exhibit dense and homogeneous networks, while heat-treated GDL gels show more porous networks. Mid-infrared (3000–2800 cm⁻¹, 1700–1500 cm⁻¹, and 1500–900 cm⁻¹) and fluorescence spectra revealed changes in protein–protein, protein–water, and protein–protein–lipid interactions throughout coagulation. Full article

The present study evaluated the effects of sugarcane-derived polyphenol nutritional supplement on milk production, milk composition, and somatic cell count (SCC) in lactating Holstein cows. A second objective was to evaluate the quality and stability of yogurt produced with milk from supplemented cows. Sixteen cows (20 ± 2 L/d milk, 120 ± 21 days in milk, 550 ± 82 kg body weight) were assigned to either a control group or a polyphenol-supplemented group in a randomized block design for a six-week evaluation period. Milk yield and individual milk samples for composition analysis (fat, protein, lactose, non-fat solids, casein, free fatty acids, and milk urea nitrogen) were recorded weekly, and only SCC was monitored three times per week. Yogurt was produced from pooled milk of each treatment and evaluated for fermentation parameters (pH, titratable acidity), shelf life, and sensory attributes were evaluated using a triangle test (discriminative sensory analysis). Polyphenol supplementation did not significantly affect milk yield or composition (p > 0.05), but reduced SCC considerably (238 × 10³ vs. 593 × 10³ cells/mL; p < 0.01). Yogurt fermentation and storage parameters were not significantly affected by supplementation, although pH and titratable acidity changed considerably over time (p < 0.01). Sensory analysis indicated that only 37.3% of panelists correctly identified differences between yogurts, which did not differ from chance expectation in the triangle test. These results demonstrate that polyphenol supplementation can improve udder health, evidenced by reduced SCC, without compromising milk yield, composition, or yogurt quality. Polyphenols thus represent a promising nutritional supplement for enhancing dairy cow health and maintaining product quality. Full article

Milk is a highly nutritious food and a cornerstone of the human diet, supplying not only essential macronutrients but also a wide range of bioactive compounds with important functional and health-promoting properties. This study presents the first comparative analysis of ruminant (cow, goat, sheep) and equine (mare, jenny) milk samples collected in Serbia, with emphasis on their physicochemical properties, protein profile, redox characteristics, and nutritional potential. Ruminant milk had significantly higher protein concentrations, with cow and sheep milk containing the highest levels of protein. Two equine milks demonstrated a distinctive whey-to-casein protein ratio to ruminants, and a higher content of active sulfhydryl groups, correlating with improved digestibility and functional properties. Antioxidant potential was determined using spectrophotometric and electrochemical methods, confirming superior redox potential in mare’s milk, followed by jenny’s and sheep’s milk. Nutritional properties of milk separated by Principal Component Analysis highlighted species-specific profiles of equine milks as a promising alternative for individuals with an allergy to cow’s milk protein, offering enhanced antioxidant protection, bioactive compounds, and digestibility. These results support the potential of equine milk as a functional food with added value in human nutrition. Full article

This cross-sectional study investigated the associations between the acute-phase proteins (APP) serum amyloid A (SAA) and haptoglobin (Hp), herd-level factors, and the seroprevalence of respiratory pathogens in Estonian dairy herds. Serum samples were analysed from 938 cows (95 herds) and 921 heifers (94 herds). Seroprevalence was tested for bovine herpesvirus 1 (BHV-1), bovine respiratory syncytial virus (BRSV), bovine parainfluenza virus 3, bovine viral diarrhoea virus, bovine coronavirus, bovine adenovirus, and Mycoplasma bovis (M. bovis). Farm visits included questionnaires on herd management practices. Linear random-intercept regression models showed higher serum SAA concentrations in cows from farms with BHV-1 seroprevalence of >50% and on BRSV-positive farms (p < 0.05), while farms employing a veterinarian had lower serum SAA concentrations. Cows had higher serum Hp concentrations in M. bovis-positive herds (p = 0.030). In heifers, serum SAA concentrations increased with low to moderate BHV-1 seroprevalence, decreased with higher M. bovis seroprevalence, and were higher in free-stall or mixed housing compared to tie-stall housing. Heifers’ serum Hp concentrations were lower in BHV-1-positive herds, but higher in herds with breeding bulls and larger herd sizes. To conclude, APP may reflect the herd health status and management-related effects on animals, supporting their use in herd-level monitoring. Full article

The transition from energy sufficiency to deficiency triggers complex metabolic and immune adaptations that have traditionally been viewed through a reductionist pathological lens. During early lactation, coordinated mobilization of adipose tissue, muscle protein, and bone minerals supports milk synthesis, with ketogenesis specifically arising from hepatic oxidation of non–esterified fatty acids. This review introduces the Keto–Inflammatory Network (KIN), a novel framework positioning ketonemia as an evolutionarily conserved adaptive response rather than inherent metabolic dysfunction. The KIN integrates β–hydroxybutyrate (BHB) signaling with immune modulation, epigenetic regulation, circadian rhythms, and microbiota interactions. Through mechanisms including NLRP3 inflammasome inhibition, HDAC–mediated epigenetic modifications, and HCAR2 receptor activation, ketone bodies orchestrate anti–inflammatory responses while maintaining metabolic flexibility. Building upon important precedent work recognizing beneficial roles of ketones in ruminant metabolism, this review synthesizes recent advances in immunometabolism and systems biology into an integrated framework. The KIN encompasses calcium–ketone integration through the Calci–Keto–Inflammatory Code (CKIC), temporal regulation via the Ketoinflammatory Clock, and trans–kingdom signaling through microbiota interactions. In dairy cattle, this perspective reframes periparturient ketonemia as existing on a continuum from adaptive to pathological, with biological meaning determined by integrated metabolic–inflammatory patterns rather than absolute ketone concentrations. The CKIC paradigm, while requiring prospective validation, suggests novel therapeutic approaches leveraging ketone signaling for inflammatory diseases, autoimmune conditions, and metabolic disorders while challenging traditional threshold–based ketosis management strategies. This systems–level understanding opens new avenues for precision interventions that work with, rather than against, evolved adaptive mechanisms refined through millions of years of mammalian evolution. By distinguishing ketonemia (measurable ketone elevation) from pathological ketosis (dysregulated ketone accumulation), and by integrating evidence from both ruminant and monogastric models, this review provides a comprehensive framework for next–generation metabolic medicine. Full article

Enterococci are ubiquitous lactic acid bacteria frequently detected in dairy environments, where they represent an important component of the non-starter lactic acid bacteria community, particularly in artisanal cheeses produced from raw milk. Due to their metabolic versatility, enterococci may contribute to cheese ripening and the development of characteristic sensory attributes; however, their technological relevance is accompanied by growing concern regarding their role as opportunistic pathogens and reservoirs of antimicrobial resistance. This review critically summarizes current knowledge on antimicrobial resistance in enterococci isolated from milk and dairy products, with emphasis on both intrinsic and acquired resistance traits and their reported prevalence across different dairy matrices and geographical regions. Particular attention is given to artisanal cheeses, in which heterogeneous and region-specific resistance patterns have been described. Advances in whole-genome sequencing have substantially improved understanding of the genetic basis of antimicrobial resistance in dairy enterococci and have largely corroborated earlier findings obtained through phenotypic antimicrobial susceptibility testing combined with targeted resistance gene detection. Nevertheless, available data remain fragmented due to variability in study design, analytical approaches, and reporting practices. Overall, the evidence highlights the need for harmonized surveillance strategies integrating phenotypic and genomic data within a One Health framework to improve risk assessment and to better understand the role of dairy enterococci in the dissemination of antimicrobial resistance along the food chain. Full article

This study examined the effects of average daily gain (ADG) during gestation on growth, nutrient digestibility, metabolic response, and subsequent milk yield and composition in dairy heifers. Twenty pregnant Holstein × Gyr heifers (450 ± 5.0 kg; 18 ± 1.1 months) were randomly assigned to moderate (MOD; target 0.35 kg/day) or high (HIG; target 0.70 kg/day) ADG groups, and received a total mixed ration from day 70 of gestation until calving. Body growth, blood metabolites, and lactation performance after birth were measured. At calving, HIG heifers had greater body weight (p < 0.01) and thoracic perimeter (p = 0.02). Nutrient digestibility and most blood metabolites were not affected by ADG (p > 0.05), except for triiodothyronine concentrations, which differed between treatments over time (p < 0.01). Milk yield and energy-corrected milk were not affected by gestational ADG (p > 0.10), while milk fat and total solids showed numerical treatment × week interactions (p ≤ 0.10). These results indicate that higher ADG during gestation increases body reserves at calving but does not affect milk yield. The moderate ADG for Holstein × Gyr heifers during gestation may improve milk quality through higher fat and solids content, emphasizing the importance of tailoring growth strategies for heifers during gestation. Full article

Historically, methods to detect subclinical mastitis have been used to aid treatment decisions. The limitations of these tests have led to the exploration of the use of differential somatic cell count (DSCC). The objective of this study was to evaluate the relationship between DSCC and antibiotic success in subclinically infected cows. Cows were pre-screened to confirm an SCC ≥ 200,000 cells/mL and a positive bacterial culture. At enrollment, aseptic quarter milk samples were collected for culturing and evaluated using SCC, DSCC, the California Mastitis Test (CMT), and electrical conductivity. Enrolled quarters were treated with an intramammary antibiotic and resampled 7-, 14-, 28-, and 35-days post-treatment and retrospectively classified as “Cured” or failed to cure (Failed) based on a bacteriological cure. The overall cure rate was 51.5%. Pre-treatment SCC, total leukocyte count (TLC), neutrophils, and CMT were lower in Cured quarters compared to Failed. Meanwhile, macrophage percentage was greater in Cured quarters compared to Failed. No difference was found between lymphocyte percentage and conductivity. When evaluating the use of multiple threshold optimizations to predict cure outcome, TLC tended to have the highest ranking for the metric of interest; however, SCC tended to numerically perform as well in sensitivity and specificity outside of the optimized parameter. 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

Colonial cheese production represents a valuable cultural and economic activity in southern Brazil. This study evaluated the effect of oral supplementation of dairy cows with an essential oil blend (EOB)—a combination of eucalyptus oil, peppermint oil, and menthol crystals—on the chemical composition and quality parameters of Colonial cheese during 21 days of ripening. Nine dairy cows were randomly assigned to three groups: control, EOB3.6 (3.6 g/cow/day), and EOB7.2 (7.2 g/cow/day). Milk from each treatment was used to produce Colonial cheeses, which were analyzed for physicochemical composition, texture, color, lipid profile, thiobarbituric acid reactive substances (TBARS), and microbiological quality at different ripening stages. Data were analyzed by analysis of variance (ANOVA) using SAS^® software, following verification of normality and homogeneity of variances. When assumptions were met, repeated-measures ANOVA was applied, and means were compared using Tukey’s test (p < 0.05). Sensory data were evaluated by ANOVA using XLSTAT^® (Addinsoft, Paris, France). EOB supplementation maintained the physicochemical integrity of the cheeses, with a gradual increase in fat content during maturation (40 g/100 g at 21 days, p < 0.05). At seven days, the EOB7.2 treatment showed lower lipid oxidation (TBARS = 0.063, p < 0.05), indicating antioxidant potential. Significant interactions between treatment and maturation were observed for color parameters and polyunsaturated fatty acids (PUFA) (p < 0.05). Cheeses from EOB7.2 presented higher saturated fatty acids (SFA) and lower unsaturated fatty acids (UFA) compared with the control (p < 0.05). No Salmonella spp. or Staphylococcal enterotoxins were detected. Counts of coagulase-positive Staphylococcus, molds, and yeasts remained stable, while Escherichia coli counts were lower in EOB-supplemented cheeses throughout ripening. Overall, EOB supplementation improved oxidative stability and microbiological safety without compromising the technological or compositional quality of Colonial cheese. Full article