Modern broiler chickens have been selectively bred for growth rates so extreme that many suffer chronic leg pain, cardiovascular disease, and impaired mobility before reaching slaughter weight at 6-7 weeks of age.
Broiler chicken welfare represents one of the most significant animal welfare problems in modern food systems by virtue of scale and severity. Over 70 billion broiler chickens are slaughtered annually, the majority suffering varying degrees of chronic musculoskeletal pain and cardiovascular compromise due to their extreme growth rate. The genetics of modern broilers have created animals whose muscle mass grows faster than their skeletal, cardiovascular, and respiratory systems can support. The resulting chronic pain from leg disorders affects billions of individuals annually. The solution is technically straightforward: slower-growing breeds reduce these welfare problems dramatically. Several major food companies have made commitments to transition to slower-growing breeds through the Better Chicken Commitment, but adoption remains incomplete.