Heat stress is one of the most significant and growing welfare problems facing dairy and beef cattle worldwide, with serious consequences for animal health, productivity, and wellbeing.
Heat stress in cattle causes genuine suffering — animals experiencing severe heat stress are in physiological distress equivalent to a human suffering heat exhaustion. Prolonged heat stress suppresses immune function, exacerbates lameness, increases susceptibility to respiratory disease, and causes reproductive failure. The welfare consequences extend beyond the individual to affect the entire herd through increased disease pressure. Many intensive operations lack adequate cooling infrastructure, either due to cost or because heat stress is normalized as an acceptable production loss. Welfare-focused farming requires shade as a minimum standard, with active cooling (fans and water sprinklers) as best practice in hot climates. Heat action plans should be mandatory components of farm management.