Broiler chickens are particularly vulnerable to heat stress due to their fast growth rate and consequent high metabolic heat production. Ventilation management and cooling systems are essential welfare tools in hot climates.
Heat stress in broiler chickens causes a welfare burden that increases as climate change drives summer temperatures higher across major producing regions. Fast-growing breeds are particularly vulnerable because their high growth rate generates substantial metabolic heat independent of ambient temperature. Birds that cannot dissipate this heat effectively through panting experience progressive hyperthermia, lethargy, and in severe cases death from heat stroke. Ventilation management is the primary welfare tool: inadequate ventilation during heat events is directly responsible for mortality events where thousands of birds die in a single building. Welfare-positive heat management requires proactive action before heat stress develops: reducing stocking density before hot periods, ensuring ventilation systems are maintained and operational, and having contingency plans for extended power outages that disable ventilation.