Slow-Growing Broiler Breeds: A Path to Better Chicken Welfare

Transitioning from conventional fast-growing broilers to slower-growing breeds is one of the most impactful welfare interventions available in commercial chicken production, addressing the root cause of production-related disease.

Key Facts

Conventional broiler breeds reach market weight in 35-42 days through intensive genetic selection for rapid muscle accretion; this growth rate causes severe musculoskeletal, cardiovascular, and metabolic problems.
Slower-growing breeds reach market weight in 56-81 days; they have lower rates of lameness, contact dermatitis, heart disease, and ascites than fast-growing counterparts.
Studies comparing fast and slow-growing breeds consistently show that slow-growing birds are more active, spend more time foraging and perching, and show fewer gait abnormalities.
The Better Chicken Commitment specifies use of breeds meeting minimum welfare criteria including maximum 6-hour dark period, stocking density limits, and enrichment — effectively excluding the very fastest-growing breeds.
Price premium requirements for slower-growing chicken add approximately 5-15% to production costs; consumer and retailer willingness to pay this premium determines adoption rates.
Major European food companies including IKEA, Sodexo, and Compass Group have committed to slower-growing breeds; North American adoption has been slower.
Breed selection is considered by welfare scientists to be the single most impactful lever for improving broiler welfare at scale.

Welfare Considerations

The welfare case for slower-growing broiler breeds is grounded in the fundamental biology of growth rate and physiological capacity. Conventional fast-growing breeds are metabolically challenged: their hearts, lungs, and skeletal systems cannot adequately support the muscle mass they are genetically programmed to accumulate in 35 days. The result is a population-level welfare crisis with high rates of lameness (painful, limiting normal movement), leg deformities, sudden death syndrome from cardiac failure, and ascites from pulmonary hypertension. These are not occasional welfare problems — they affect 15-30% of birds in some studies. Slower-growing breeds do not eliminate welfare challenges but substantially reduce the prevalence and severity of production-related disease, enabling birds to live their abbreviated lives with meaningfully lower rates of chronic pain and physiological compromise.

What You Can Do

Choose chicken products from companies committed to the Better Chicken Commitment with slower-growing breed requirements.
Support retailers and food service companies that have made and are meeting breed welfare commitments.
Reduce chicken consumption overall or shift to suppliers who transparently report breed welfare metrics.
Advocate for breed welfare standards in national poultry welfare legislation.
Support farm animal welfare organizations tracking corporate commitments and holding companies accountable.