Conventional broiler chickens have been bred for such rapid growth that they often suffer from severe health problems before slaughter age.
The genetic selection for rapid muscle growth has created chickens whose physiology is fundamentally compromised. Their cardiovascular and skeletal systems cannot keep pace with muscle development, causing widespread suffering. Transitioning to slower-growing breeds addresses the root cause rather than merely treating symptoms. The welfare gap between conventional and slower-growing breeds is among the most clearly documented improvements available in commercial poultry.