Heat stress in broiler and layer poultry is a major welfare and production concern in hot climates, causing panting, reduced feed intake, and mortality in poorly ventilated housing.
Poultry are particularly vulnerable to heat stress because they cannot sweat and rely on panting and air movement for cooling. In densely stocked commercial housing, heat from animal bodies accumulates rapidly; without adequate ventilation and cooling, temperatures can rise to lethal levels during hot weather events. Individual birds in the final days before slaughter, when they are at maximum weight and metabolic output, are most vulnerable. The welfare impact includes panting, reduced movement, crowding near water, and in extreme cases, mass mortality. Investment in heat management infrastructure is both a welfare obligation and a commercial necessity.