Heat stress in dairy cattle causes significant welfare harm and production losses, but effective cooling systems can substantially reduce its impact on animal wellbeing and health.
Heat stress causes genuine suffering in dairy cattle — animals in thermal stress show increased respiratory rates, drooling, reduced activity, and huddling behaviour that disrupts normal social patterns. Chronic heat stress impairs immune function, increasing susceptibility to mastitis and other infections. The welfare case for heat abatement investment is strong and is reinforced by the substantial production benefits, making it one of the most tractable farm animal welfare improvements with clear economic incentives for producers. Failure to provide adequate cooling infrastructure — particularly as climate change increases the frequency and severity of heat events — represents an avoidable welfare harm. Transition cow cooling is especially important given the evidence that heat stress in late pregnancy causes persistent effects on calves that continue through their productive lives.