Heat waves create acute welfare emergencies for farm animals, particularly poultry and pigs, whose physiological heat tolerance is limited and whose housing often lacks adequate cooling.
Heat wave poultry mortality is among the most acute and visible farm animal welfare disasters. In a single extreme heat event, millions of birds can die within hours when ventilation systems fail or temperature exceeds cooling capacity. Deaths involve heat-induced seizures and cardiovascular collapse preceded by severe distress. Pre-heatwave planning — system redundancy, emergency cooling capacity, mortality threshold stocking densities — prevents most deaths but requires regulatory standards to become universal.