Search Results (199)

The expansion of digital technologies in dairy farming (precision dairy farming) has created new opportunities for the systematic use of data, which can lead to more efficient production processes. This study aimed to develop and evaluate models for predicting daily milk yield from dairy cows during summer. This yield was modeled at the individual level, with days in milk and parity group included as baseline covariates in all analyses. Three feature-set scenarios were defined and evaluated, in which the temperature–humidity index (THI) and milk yield history were added to the baseline variables either separately (Scenarios 1 and 2) or jointly (Scenario 3). Performance was evaluated using walk-forward validation, and feature selection was nested within each iteration’s training window. The performance of the linear mixed model (LMM) was then compared with two machine learning models, random forest (RF) and gradient boosting machine (GBM), within the same experimental framework. In Scenario 3, all three models showed similar fits (R² = 0.92 and concordance correlation coefficient = 0.96), although the GBM model yielded a smaller error (root mean square error [RMSE] = 2.07 ± 0.22, mean absolute error [MAE] = 1.39 ± 0.12) than the RF model (RMSE = 2.10 ± 0.23, MAE = 1.45 ± 0.13) and the LMM (RMSE = 2.15 ± 0.22, MAE = 1.41 ± 0.10). Overall, adding the THI and recent milk yield history to the baseline variables improved short-term prediction accuracy in this dataset, with the GBM model showing the smallest error. These results can support farmers and herd managers in predicting short-term milk yield under heat stress conditions and making timely management decisions. Full article

Milk production in dairy herds is determined by both intrinsic and extrinsic factors, with reproductive efficiency serving as a primary determinant. Infectious, nutritional, and management-related challenges can reduce this efficiency. Following parturition, cows are more susceptible to clinical disorders due to a temporary loss of integrity in the cervix, vagina, and vulva, which allows environmental bacteria to ascend and alter the vaginal microbiota. These microbial changes may disrupt endocrine responses related to conception and contribute to repeat breeder cow syndrome (RBCS), which is defined as failure to conceive after three or more inseminations. This study investigated associations among cultivable vaginal bacteria, circulating progesterone and glucose concentrations, and reproductive performance in 30 fourth-parity Holstein cows with a body condition score of 3.5. Cows were classified by reproductive history as repeat breeders (RBCS; n = 14) or controls (CTL; n = 16). Vaginal mucosal samples were collected at insemination and cultured on blood agar and MacConkey media under aerobic and microaerobic conditions. Bacterial identification was conducted using Gram staining and standard biochemical assays. Blood samples were collected at insemination, on day 5 post-insemination, and every two days thereafter to measure progesterone and glucose concentrations. Fertility outcomes were analyzed using PROC GLIMMIX, and hormonal data were analyzed using mixed models with repeated measures. The bacterial genera identified included Bacillus, Escherichia coli, Staphylococcus, Klebsiella, Proteus, Streptococcus, and Actinomyces. Progesterone and glucose concentrations did not differ significantly between groups (p > 0.05). However, the fertility rate (p < 0.05; CTL:87.50% vs. RBCS:57.14%) and number of attempts to conceive (p < 0.001; CTL:2.5 vs. RBCS:6.7) differed statistically between treatments. A higher prevalence of S. hyicus was detected in RBCS cows, and E. coli, S. hyicus, and Proteus spp. were more frequently detected in non-pregnant cows. These findings suggest that the identified cultivable vaginal bacteria are associated with reproductive status in dairy cows. Full article

This study presents the first molecular investigation into the prevalence and risk factors of Eimeria spp. infection among weaned dairy calves in Thessaly, Greece. Utilizing a cross-sectional design, 665 fecal samples were collected from 35 intensive dairy cattle farms and analyzed via genus-specific PCR and species-specific multiplex PCR targeting the internal transcribed spacer 1 (ITS-1) region. The overall molecular prevalence was found to be 46.3%, with Eimeria bovis (24.7%) and Eimeria zuernii (14.0%) emerging as the most prevalent species. Mixed infections were common, occurring in 51.0% of the positive cases. Multivariable analysis revealed that dairy calves aged less than 60 days had 2.15 times higher odds of infection compared to older calves. Environmental factors also significantly influenced infection rates, specifically ground flooring, the use of immovable/concrete water troughs and infrequent cleaning of floors, feeders and water troughs. These results highlight the high burden of pathogenic Eimeria in dairy cattle herds of Thessaly, Greece, and underscore the importance of integrating rigorous hygiene protocols with age-targeted management to control bovine coccidiosis. Full article

To monitor the epidemiological situation of bluetongue virus (BTV) in Belgium, a national surveillance programme was conducted during the 2024–2025 winter season. The objective was to estimate the apparent seroprevalence of BTV-3 following the 2023–2024 epidemic and to prove the absence of active circulation of other BTV serotypes in mixed herds (cattle and sheep). A total of 2551 cattle and 1458 sheep were sampled across Belgium. Serological analyses were performed using ELISA, and molecular detection of BTV-3, BTV-8, and BTV-12 was conducted by RT-qPCR. The majority of cattle and sheep herds showed evidence of exposure to BTV-3, with a very high herd-level apparent seroprevalence (100%; 95% CI: 96.2–100% in cattle and 98.9%; 95% CI: 93.8–99.8% in sheep). Apparent within-herd seroprevalence was also high in cattle (94.6%; 95% CI: 91.8–96.5%) and sheep (85.5%; 95% CI: 80.4–89.5%). No evidence of active circulation of BTV-8 or BTV-12 was detected. A moderate significant positive correlation between Ct values and sampling date was observed both for bovine and ovine samples, consistent with a progressive decline in detectable BTV RNA during winter in the absence of vector activity. Full article

The longitudinal study investigated the impact of age at first mating (AFM) on milk yield (MY) across the productive lifespan of Alpine goats born between 2005 and 2018. Data from 740 animals across three herds and 3200 lactations were analyzed. The AFM of the studied population ranged from 7 to 23 months. The impact of AFM on MY was estimated using a linear mixed model, accounting for the fixed effects of parity, litter size, season, herd, and suckling and milking durations, with the individual goat included as a random effect to control for repeated measures. The impact of AFM on lifetime production was estimated by regressing total milk yield (TMY) and number of lactations (TNL) on AFM, while accounting for herd effect. The study revealed a notable shift in productivity patterns across the animal’s life. Every additional month of AFM significantly increased milk yield in the first lactation (13.28 kg; p < 0.001), but this influence vanished in subsequent parities (p > 0.05). These higher initial yields were insufficient to compensate for the losses caused by a shortened productive lifespan. Specifically, each month of mating delay resulted in a loss of ~0.08 TNL and 34 kg TMY, totaling ~1 lactation and ~400 kg of milk for a 12-month delay. Results suggest that earlier mating may improve lifetime productivity under intensive production systems. Full article

This study investigates the typology of the pastoral farming systems in the arid region of southern Tunisia, with a particular focus on the governorate of Tataouine. A field survey was conducted among 111 livestock farmers distributed across different agro-ecological zones. The typology of breeding systems was established using a Factor Analysis of Mixed Data (FAMD), which identified eleven dimensions explaining 69.74% of the total data variance. The first three dimensions accounted for 15.91%, 8.79%, and 7.67% of the variability, respectively, and were defined by herd composition, resource availability, and management strategies, including variables such as the number of goats, sheep, and camels, distance to water sources, infrastructure, reproductive practices, and workforce availability. Hierarchical clustering revealed three distinct systems: System 1, regrouping “Small Urban Farmers”, defined by small-scale operations relying on family labor, localized feed resources, and market-driven production targeting urban consumers; System 2, representing large livestock, composed of professionalized operations with improved infrastructure, hired labor, and transhumance practices to optimize resource use and productivity; and System 3, for herds with camels, characterized by extensive systems utilizing collective rangelands and camels to adapt to arid conditions and ensure ecological resilience. The results emphasize how ecological constraints, infrastructure, and spatial organization shape the diversity of these systems. This typology provides critical insights into the challenges and potential of livestock farming in arid environments and offers a foundation for designing targeted interventions to support the sustainability of pastoral systems under increasing environmental and economic pressures. Full article

Highly pathogenic avian influenza virus of the H5N1 subtype has been infecting U.S. dairy cattle and spreading among dairy operations since March 2024. H5N1 surveillance systems for dairies are needed, but information on whether environmental sampling can inform these systems is lacking. To guide a surveillance framework, we determined the environmental sites with Influenza A virus (IAV) detection on H5N1-affected dairies (n = 25) in four states (California, Colorado, Michigan, and Ohio) and explored sample characteristics that may have influenced detection. A total of 581 samples from dairy environmental sites were characterized for IAV RNA via rRT-PCR, and classified into six categories. A total of 94 samples (16.2%) had IAV detected, and the Ct values measured from these samples were typically higher than those measured in bulk tank milk from a subset of sampled herds. A majority of IAV detections were made from the following site categories: milking equipment/personal protective equipment, parlor surfaces, and wastewater/lagoons/manure. These results suggest that environmental sites most likely to be contaminated with IAV on dairies are those with exposure to milk. Meanwhile, mixed effect logistic modeling showed that days into an outbreak that samples were collected was associated with IAV detection. These results provide a framework within which to continue the assessment of environmental sampling as a surveillance tool for dairy H5N1. This framework can be strengthened by studies that perform further IAV viral characterization and collect samples from sites prior to, during, and after H5N1 outbreak periods. Full article

The objective of this study was to evaluate the impact of summer calving on reproductive performance, milk yield, and culling risk in U.S. organic dairy herds. Data were obtained from the Dairy Herd Improvement records of 434 organic dairy herds across 31 states, comprising 287,927 calving records from 2018 to 2022. Calving months were categorized as winter, spring, summer, or fall. Mixed models were used to analyze the 305 d milk yield, 305 d energy-corrected milk yield, peak milk DIM, peak test-day milk yield and logistic regression, and survival analyseswere applied to analyze calving difficulty, abortion, pregnancy diagnosis, and culling outcomes. Cows calving during summer had fewer days to first service and fewer days open compared with cows calving in other seasons; however, their odds of being diagnosed as pregnant were significantly lower. Summer-calving cows produced lower 305 d milk and energy-corrected milk yields, reached peak milk production later, and had a lower peak test-day milk yield. Calving during summer was also associated with increased odds of calving difficulty and a higher risk of culling. These findings indicate that summer calving poses distinct challenges for organic dairy cows, with cumulative effects on fertility, milk production, and survivability, underscoring the need for season-specific management strategies in organic dairy systems. Full article

The CSN2 gene encoding β-casein has gained increasing attention in dairy cattle breeding due to the global adoption of A2-oriented selection strategies. However, robust large-scale evidence assessing potential unintended effects on functional traits, particularly fertility, under intensive commercial conditions remains limited. This study evaluated whether selection for the CSN2 A2 β-casein variant is associated with biologically relevant differences in fertility traits in Holstein cows. Reproductive and genomic data from 7826 lactation records of 2773 Holstein cows collected between 2022 and 2025 in a large commercial dairy herd were analyzed. Fertility indicators included days open, number of services per conception, calving interval, first-service conception rate, and pregnancy by 100 days in milk. Mixed-effects models accounting for repeated lactations and cow- and sire-level clustering were applied, and predefined equivalence margins were used to distinguish statistical non-significance from biological irrelevance. Across all evaluated fertility traits, differences among CSN2 genotypes (A1A1, A1A2, and A2A2) were consistently small, biologically negligible, and well within predefined equivalence margins. Differences in days open were within ±2 days, and effect sizes for count and binary traits were close to unity. Parity and calving year significantly influenced reproductive performance, whereas no CSN2 genotype × parity interactions were detected. These findings indicate that selection for the CSN2 A2 β-casein variant does not compromise reproductive performance under intensive commercial management conditions. From a breeding and industry perspective, the results support the implementation of A2-oriented selection strategies without biologically meaningful adverse effects on fertility. 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 objectives of this study were (i) to analyze the ClassyFarm welfare scores in loose housing system (LHS) and tied housing system (THS) Rendena herds, and (ii) to investigate the influence of the housing on individual milk yield and quality traits in Rendena cows. The dataset consisted of 3761 individual milk samples from 750 Rendena cows, collected between August 2022 and November 2023 from 17 single-breed herds of the Veneto region. Available data included days in milk (DIM), parity, and milk yield, as well as fat, protein, casein, and lactose contents, somatic cell count, differential somatic cell count, and urea concentration. For milk traits, a linear mixed model included housing system, DIM, and parity as fixed effects, while cow, herd-test-date, and residual variability were random effects. In both housing systems, a good level of welfare was observed, although shortcomings in biosecurity measures were identified in both LHS and THS. Milk quality (in terms of protein % and casein %) and yield were higher in LHS compared to THS. The observed differences cannot be explained by the housing system alone, as other management and nutritional factors may have played a role, highlighting the need for further studies to clarify these contributions. Full article

Piglets are highly susceptible to iron deficiency. This randomized clinical trial evaluated the effectiveness of four iron dosing schemes in preventing anemia. Two herds with different farrowing management systems were included. In each herd, 40 litters (6 piglets/litter) were selected on day 3 of age. A 2 × 2 factorial design was applied, combining two intramuscular iron dextran injection schemes [37.5 mg Fe/kg (low injection; LI) or 150 mg Fe/kg (high injection; HI)] with two oral ferrous sulphate feed supplementation schemes [125 mg Fe/kg (low feed; LF) or 200 mg Fe/kg (high feed; HF)]. Blood samples were collected at 4 and 20 days of age, and piglets were weighed at 3 and 20 days. Data were analyzed using linear mixed models, with significance set at p < 0.05. In Herd A, HI-LF piglets showed increased body weight, whereas no growth differences were observed in Herd B. Creep-feed intake did not differ between treatments. HI consistently improved red-cell indices in Herd A, while in Herd B LI piglets initially showed higher values at day 4, but HI piglets surpassed them by day 20. Leukocyte responses were limited. High-dose iron injections were effective in preventing anemia, while oral supplementation had minimal impact. Full article

The polymorphism of the bovine β-casein gene (CSN2) is of increasing interest due to its relevance for A2 milk production. This study genotyped 2773 Holstein-Friesian cows for five CSN2 alleles (A1, A2, A3, B, I) using both conventional DNA-based PCR and a newly evaluated direct PCR protocol. Eleven genotypes were detected, with A2/A2 (33.9%) and A1/A2 (30.3%) being the most common, resulting in an A2 allele frequency of 59.0%. Genetic diversity indices indicated moderate polymorphism and a significant deviation from Hardy–Weinberg equilibrium, consistent with ongoing selection for the A2 allele. Associations between CSN2 genotype and milk traits (305-day milk, fat, and protein yield; fat% and protein%) were evaluated using linear mixed-effects models including lactation number, age at calving, and calving year as covariates, and cow ID as a random intercept. Several genotype effects reached statistical significance (p < 0.05); however, all effect sizes were very small (partial η² < 0.01), indicating that any influence of CSN2 on production traits is negligible within this population and management context. These findings suggest that A2-oriented selection is unlikely to compromise productivity. The direct PCR genotyping method achieved 96–100% success and enabled substantially faster and more cost-efficient processing (approximately 80–90% reduction in reagent costs), providing a rapid and scalable approach for large herds. Full article

Pathogens such as Toxoplasma gondii, lentiviruses (e.g., CAE), Hypoderma spp., Neospora caninum, Mycoplasma spp., and pestiviruses are important for goat farming in Lithuania; however, data on their prevalence remain limited. To address this gap, a multi-pathogen study was conducted between 2021 and 2024 using selected ELISA kits (ID.vet, Innovative Diagnostics, France). A total of 380 blood samples were collected from 30 goat herds across different regions of Lithuania; the sample size varied depending on the pathogen. Serum samples were tested for antibodies, and seroprevalence was calculated for each pathogen. The highest seroprevalence was detected for T. gondii (38.9%, 143/368) and CAE virus (19.5%, 74/380). Antibodies to Mycoplasma spp. (0.3%, 1/368), Hypoderma spp. (3.8%, 7/184), and N. caninum (0.5%, 2/368) were detected only sporadically, while no antibodies to Border disease virus or Q fever were identified. Mixed infections were found in 7.6% of samples. Chi-square analysis showed that co-infections with toxoplasmosis and CAE occurred more frequently than expected (χ² = 19.05, p < 0.001). Herd size was significantly associated only with CAE seroprevalence (χ² = 7.913, df = 1, p < 0.05). Overall, toxoplasmosis and CAE were identified as the most epidemiologically relevant infections in the Lithuanian goat population. Full article

Livestock production in the high Andes is vital for rural livelihoods and food security but is limited by poor pasture quality, environmental variability, and restricted resources. Pasture improvement, achieved through management practices and particularly through fertilization, may enhance productivity and sustainability in high-Andean livestock systems. This study aimed to characterize mixed herds composed of domestic sheep (Ovis aries), alpacas (Vicugna pacos), llamas (Lama glama), and domestic cattle (Bos taurus) and to evaluate the role of pasture fertilization on herd composition and livestock size. Primary data were collected through structured questionnaires administered to 88 randomly selected livestock producers, complemented by direct field observations of grazing areas, corrals, shelters, and water sources. The survey documented herd structure, grazing management, pasture conservation, fertilization practices, and farm infrastructure. Data from multiple farms were analyzed using a clustering approach to group production units with similar characteristics, and statistical models were applied to assess the effects of fertilization, pasture area, and water sources. Three distinct clusters were identified: one dominated by alpacas, another by sheep, and a third by llamas with the most uniform stocking density. Pasture fertilization was most common in the sheep-dominated cluster and was significantly associated with higher sheep numbers, while no significant effects were detected for alpacas, llamas, or cattle. Farms without fertilization showed slightly higher overall livestock size; however, a strong negative interaction between pasture area and lack of fertilization indicated that expanding grazing land alone could not offset low forage quality. These findings suggest that targeted fertilization, when combined with sustainable grazing practices, may contribute to improved herd performance and long-term resilience in heterogeneous Andean livestock systems. Full article