Heat stress reduces productivity and compromises welfare in tropical beef cattle. We assessed the effectiveness of various shade structures in 180 Brahman-cross cattle across six Malaysian farms. Animals with access to shade had lower rectal temperatures, reduced respiration rates, and increased grazing time during hot periods. Shade cloth structures providing 80% solar blockage optimized cost-effectiveness. Shaded cattle gained 0.18 kg per day more than unshaded controls during the hot season. Simple interventions significantly improve thermal comfort and productivity in extensive tropical systems.

Bovine viral diarrhea virus causes substantial reproductive and immunological impacts in beef herds. We evaluated modified-live and killed vaccine protocols in 24 cow-calf operations over three consecutive breeding seasons. Pre-breeding vaccination with modified-live vaccine reduced fetal infection rates from 8.2% to 1.4%. Antibody titers persisted through gestation in vaccinated dams, with passive transfer protecting calves through weaning. Comprehensive vaccination programs combined with biosecurity measures achieved BVDV-negative status in 83% of participating herds. Results demonstrate achievable control strategies for endemic infections.

Antimicrobial stewardship is particularly critical in organic dairy production where therapeutic options are limited. We characterized antimicrobial susceptibility of 412 bacterial isolates from clinical mastitis cases across 45 Danish organic dairy farms. Staphylococcus aureus and Streptococcus uberis predominated. Penicillin resistance occurred in 23% of staphylococcal isolates, while streptococci remained largely susceptible. Multidrug resistance was uncommon but increased over the five-year study period. Results support targeted narrow-spectrum antimicrobial selection and highlight the importance of ongoing surveillance in organic systems.

Lameness causes significant economic losses and welfare concerns in dairy production systems. We surveyed hoof health in 640 cows from 128 smallholder farms in central Kenya. Overall hoof lesion prevalence was 34%, with sole ulcers and white line disease most common. Risk factors included zero-grazing housing, concrete flooring without bedding, and irregular hoof trimming. Farms practicing routine hoof care had 58% lower lesion prevalence. Training programs for smallholder farmers on hoof management could substantially improve cattle welfare and productivity in resource-limited settings.

Hepatic lipidosis during the transition period contributes to metabolic dysfunction in dairy cattle. We developed and validated an ultrasonographic scoring system for liver fat assessment in 180 periparturient Holstein cows. Ultrasound scores correlated strongly with hepatic triglyceride concentrations determined by biopsy. Cows with high ultrasound scores at calving had 2.4-fold increased risk of developing clinical ketosis. The non-invasive technique enables repeated monitoring without tissue sampling. Early identification of cows with excessive hepatic fat accumulation facilitates targeted nutritional interventions during the critical transition period.

Bovine respiratory disease remains the leading cause of morbidity and mortality in feedlot cattle. We evaluated serum biomarkers for early BRD detection in 450 newly arrived feedlot calves. Haptoglobin, serum amyloid A, and fibrinogen concentrations were measured at arrival and weekly for six weeks. Elevated haptoglobin at arrival predicted subsequent BRD development with 82% sensitivity and 71% specificity. Combined biomarker panels improved diagnostic accuracy to 89%. Early identification of at-risk animals enables targeted metaphylactic interventions, potentially reducing antimicrobial usage while maintaining animal welfare.

Clinical endometritis significantly impacts dairy cattle fertility and farm profitability. We compared four intrauterine treatment protocols in 320 postpartum Holstein cows with diagnosed endometritis. Treatments included cephapirin, oxytetracycline, chlorhexidine, and saline control. Cephapirin achieved highest bacteriological cure rates at 78% versus 61% for oxytetracycline. First-service conception rates improved significantly in treated groups compared to controls. Time to first insemination decreased by 12 days in cephapirin-treated animals. Economic analysis demonstrated favorable cost-benefit ratios for antimicrobial treatments despite withdrawal period considerations.

This study evaluates indoor air quality (IAQ) and associated health risks in 122 households with children across coastal urban (n = 40), inland urban (n = 45), and coastal rural (n = 37) areas of Qingdao, China. Indoor pollutants, including particulate matter, volatile organic compounds, and biological contaminants, were measured alongside environmental indicators. Health symptoms and household characteristics were assessed via questionnaires. Results revealed significant seasonal and spatial variations in IAQ. Elevated temperatures were associated with inattention (odds ratio [OR] = 4.2, 95% confidence interval [CI]: 1.18–14.97) and cold symptoms (OR = 12.41, 95% CI: 1.55–99.04). Xylene exposure correlated with inattention (OR = 3.60, 95% CI: 1.01–12.82) and cold symptoms (OR = 4.07, 95% CI: 1.15–14.33). Carbon monoxide (CO) exposure was linked to dry eye (OR = 3.71, 95% CI: 1.11–12.43) and pruritus (OR = 9.63, 95% CI: 1.59–58.21). Benzene exposure was associated with headaches (OR = 5.15, 95% CI: 1.2–22.16), and fungi exposure with dizziness (OR = 7.32, 95% CI: 1.58–34.02). Modern dwelling features, such as double-layered windows and central heating, significantly influenced pollutant levels. Formaldehyde posed a notable carcinogenic risk (excess risk [ER] for maximum concentration: 2.83 × 10⁻⁵) and exceeded hazard thresholds (hazard quotient [HQ]: 1.52). Findings highlight the need for targeted interventions in building design and ventilation strategies, particularly in coastal regions with distinct seasonal patterns.

This trial addresses the hypothesis that Cryptosporidium spp. causes intestinal infections in calves worldwide and nitazoxanide (NTZ) has shown antiprotozoal activity. Yet, dosing and safety data are scarce. The effects of a commercial formulation of NTZ were evaluated in Cryptosporidium - positive herd consisting of 150, 2-day old diarrhea-free Holstein/Brangus male calves randomly assigned to a prophylactic (n = 50); treatment (n = 50); or untreated (n = 50) group. If out of protocol intervention was allowed, a negative outcome was registered. 50 mg/kg of NTZ were administered as an oral drench on either day 2 to 6 (prophylactic protocol) or on days 7 to 16 (treatment protocol). Weight and parasitic load were measured on days 0, 12, 30 and 60. NTZ controlled diarrhea in all cases, both groups, while untreated calves were regarded as recovery failures on day 10 and were treated as required. The severity of diarrhea and oocyst count shedding decreased earlier in the prophylactic group. Calves treated prophylactically gained significantly more weight than animals in the treatment group. No apparent adverse reactions were observed due to NTZ. Hence, it is here proposed to use NTZ prophylactically to treat cryptosporidiosis. Management practices to improve calves’ housing are mandatory.