Farmed Chicken Breed Reform: The Welfare Case for Slower-Growing Birds

The intensive selective breeding of broiler chickens for extreme growth rate has created a suite of welfare problems that can only be fully resolved by shifting to slower-growing breeds with better welfare profiles.

Key Facts

Modern commercial broiler breeds are typically slaughtered at 5-6 weeks of age having grown from 40g to 2.5kg
Growth rates in fast-growing breeds have approximately doubled since the 1970s; daily weight gain of 60-70g is common
Cardiovascular problems (heart attacks and ascites) are estimated to cause 1-3% mortality in fast-growing flocks
Leg disorders are near-universal at slaughter weight; lame birds experience chronic pain in the final weeks of life
Hock burn (contact dermatitis from litter contact) is an outcome welfare measure used to score flock conditions
Slower-growing breeds including the RSPCA Assured 'higher welfare' breeds grow at significantly lower rates over longer periods
Research shows slower-growing birds spend more time walking, foraging, and exploring, demonstrating better welfare
The BBFAW (Business Benchmark on Farm Animal Welfare) tracks progress by major food companies toward slower-growing breed commitments

Welfare Considerations

Broiler breed is the most fundamental welfare factor in chicken production - choosing a faster or slower-growing breed sets the ceiling on achievable welfare outcomes regardless of how good the husbandry is. Fast-growing breeds suffer cardiovascular failure, skeletal collapse, and leg pain that no amount of good management can fully prevent. Slower-growing breeds have better physiological resilience and express more natural behaviour. Major food companies that have committed to higher welfare chicken standards have made slower-growing breeds central to those commitments - consumer pressure is the most effective lever for accelerating adoption.

What You Can Do

Choose chicken products from RSPCA Assured or equivalent schemes specifying slower-growing breeds
Ask fast food chains, supermarkets, and food service providers about their broiler breed commitments
Support campaigns like Open Wing Alliance's Better Chicken Commitment
Reduce chicken consumption as a direct response to the welfare challenges of intensive broiler production
Donate to farm animal welfare organisations campaigning for broiler breed reform at scale