Extreme heat events pose acute mortality and welfare crises for broiler chickens, whose limited thermoregulatory capacity and high stocking densities make them uniquely vulnerable to heat-related suffering and death.
Broiler heat stress causes suffering that ranges from chronic discomfort in persistently warm conditions to acute, painful death in ventilation failure events. The combination of extreme growth rate, high stocking density, and limited thermoregulatory capacity makes commercial broilers uniquely vulnerable. A flock of 40,000 birds in a sealed, unventilated barn during a summer heatwave can experience a complete mortality event within hours — a welfare catastrophe of enormous scale. Climate change is increasing the frequency and severity of heat events, making thermal welfare management increasingly critical. Infrastructure investment in emergency generators, temperature monitoring with remote alerts, and climate-resilient barn design is welfare-essential. Breed selection that moves toward slower-growing genetics with better heat tolerance addresses the problem at source and represents a long-term welfare improvement beyond management fixes.