White striping and wooden breast myopathy affect the majority of fast-growing broiler chickens, causing muscle degeneration and reduced welfare. Slowing growth rates is the primary solution.
Broiler breast myopathy represents a systemic welfare failure caused by decades of selection for extreme growth and breast mass without adequate attention to the physiological sustainability of that growth. The muscle fibers of fast-growing broilers outgrow their blood supply, resulting in localized oxygen deprivation, inflammation, and muscle cell death. The resulting conditions cause pain, altered gait, and reduced activity in affected birds. Because myopathy is endemic in fast-growing breeds, the welfare problem is not an exception but the norm in conventional broiler production. The solution is straightforward but economically disruptive: slowing growth rates to what the body can sustain. Slower-growing breeds achieve this at modest cost increases, and a growing number of food companies have committed to requiring them from suppliers.