Modern broiler chickens are bred to grow so fast that their bodies cannot cope. Leg problems, heart failure, and respiratory disease are endemic in commercial broiler production.
The selective breeding of broilers for rapid growth has created animals whose bodies are fundamentally incompatible with healthy living. Lameness from insufficient skeletal development, cardiovascular failure from demands placed on the heart, and skin lesions from lying on soiled litter affect billions of birds annually. Switching to slower-growing breeds significantly reduces these welfare impacts, though it increases production costs.