Broiler Breast Myopathy: Welfare Implications

Understanding wooden breast and white striping myopathies in fast-growing broilers, their causes, and welfare implications for the poultry industry.

Key Facts

Wooden breast and white striping are muscle myopathies affecting up to 90% of fast-growing broiler breeds at commercial processing weights
The conditions are caused by excessive muscle growth outpacing blood supply capacity, resulting in muscle fiber degeneration
Affected birds show reduced activity levels and increased time lying, suggesting chronic discomfort or weakness
Wooden breast results in hardened, pale breast meat with reduced commercial quality alongside significant animal welfare impacts
Slower-growing breeds with 20-25% lower growth rates have dramatically reduced myopathy prevalence
The EU and major welfare certification schemes are increasingly mandating slower-growing breeds to address myopathy welfare concerns

Welfare Considerations

Breast myopathies in broilers represent a welfare crisis embedded directly in the genetics and growth rates of modern commercial poultry. The same genetic selection that produces rapid muscle growth and high breast meat yield causes muscles to outgrow their blood supply, leading to chronic hypoxia, inflammation, and fiber degeneration throughout the growing period. Birds affected by wooden breast show behavioral changes consistent with chronic pain or weakness. The solution is known: slower-growing breeds that reach market weight in 56+ days rather than 35-42 days have dramatically lower myopathy rates. The welfare cost of continuing to produce extremely fast-growing broilers is borne by billions of individual birds each year, making this one of the most numerically significant animal welfare problems in the world.

What You Can Do

Choose chicken products from certified higher-welfare schemes that mandate slower-growing breeds, such as RSPCA Assured or Better Chicken Commitment certified products
Support retailers and food companies that have signed the Better Chicken Commitment in your country
Reduce overall poultry consumption and prioritize quality over quantity when purchasing chicken
Advocate for legislation mandating maximum growth rate limits in commercial broiler production
Share information about broiler myopathies with others — most consumers are unaware of this widespread welfare problem