Archives of Current Research International

Climate-related heat stress can impair the productivity, welfare and reproductive performance of dairy cattle in tropical environments. This study evaluated whether an integrated housing modification could improve the microclimate and animal responses of early-lactation crossbred cows. Sixteen cows, balanced for parity, milk production and stage of lactation, were randomly assigned to a conventional loose-housing system or a modified shed with regulated foggers, high-speed fans, sand bedding and fenceline feeding (n = 8 per group). Microclimate, cow comfort index (CCI), dry matter intake (DMI), milk yield, reproductive traits, physiological responses and behaviour were assessed. Mean THI was lower in the modified shed than in the control shed (73.85 ± 1.07 vs 77.53 ± 1.36; P = 0.042). CCI, DMI and milk yield were higher in the treatment group (93.59 ± 1.96%, 15.28 ± 0.29 kg/cow/day and 19.54 ± 0.34 kg/cow/day, respectively) than in the control group (74.18 ± 4.89%, 13.71 ± 0.40 kg/cow/day and 16.87 ± 0.25 kg/cow/day). Days to first postpartum oestrus were lower in the treatment group (65.37 ± 4.63 vs 78.87 ± 5.33 days), whereas service period did not differ significantly. Resting and rumination times were greater, and heart rate was lower, in cows housed in the modified shed. These findings indicate that integrated structural and cooling interventions can improve thermal comfort, milk production and selected reproductive and behavioural outcomes in crossbred dairy cows under tropical conditions.