Heat stress is one of the most significant welfare and production challenges in dairy and beef cattle, causing suffering, reduced production, reproductive failure, and death — and climate change is making it worse.
Heat stress in cattle causes a cascade of welfare problems. Acutely, high body temperature causes discomfort comparable to severe fever in humans — reduced activity, altered posture (standing in water or shade), increased respiration, and physiological distress. Chronically, heat-stressed cows produce less milk, conceive less reliably, and are more vulnerable to metabolic disease. Calves born to heat-stressed dams are born immunocompromised, predisposing them to disease in the neonatal period. Feedlot cattle in intensive systems without shade or cooling face the worst welfare outcomes during heat waves. As climate change increases the frequency and severity of heat events, the welfare burden of inadequate heat stress mitigation will grow substantially, making proactive infrastructure investment both a welfare imperative and a production necessity.