Slow-growing or lower-output chicken breeds offer substantially improved welfare outcomes compared to conventional fast-growing broilers, which suffer high rates of leg problems, heart failure and chronic pain.
The welfare case for slower-growing breeds is compelling and well-evidenced. Fast-growing broilers experience chronic leg pain that limits movement and reduces access to food, water and environmental enrichment. Cardiovascular strain leads to ascites and sudden death syndrome. Slower-growing breeds have lower activity levels, better leg health, more time spent foraging and perching, and express more natural behaviours. They also appear to experience less chronic pain, as measured by gait scores and pain sensitivity tests. Transitioning the industry represents a significant welfare improvement for billions of birds annually.