Modern broiler breeds have been selected for such rapid growth that they routinely experience welfare problems including leg disorders, heart failure, and difficulty walking that affect a majority of birds.
Fast-growth broiler breeds represent a fundamental welfare problem built into genetics rather than management - birds suffer because of what they are, not how they are kept. Leg disorders, respiratory distress, and cardiovascular failure affect enormous numbers of animals in their final weeks of life. Transitioning to slower-growing breeds is the single most impactful intervention available to broiler producers, removing the genetic basis of suffering at scale.