The extreme growth rates of modern commercial broiler breeds cause significant welfare problems including leg disorders, heart disease, and chronic pain.
The extreme growth rates selected into modern broiler breeds represent perhaps the most significant genetic welfare problem in farm animal production. These birds are physiologically compromised by their own biology — their musculoskeletal and cardiovascular systems cannot keep pace with their engineered growth. The welfare costs are massive in scale given the billions of birds produced annually. Transitioning to slower-growing breeds — as required by the Better Chicken Commitment — addresses the root cause rather than managing symptoms of a broken system.