Broiler Chicken Leg Health and Gait Scoring

Leg disorders are the most significant welfare problem in commercial broiler production. Gait scoring is a validated tool for monitoring flock welfare and identifying farms needing intervention.

Key Facts

Up to 25% of commercial broilers show clinically significant leg problems in EU surveys
Common conditions include tibial dyschondroplasia, valgus-varus deformity and hock burn
Affected birds show reluctance to move, time spent lying increasing, and reduced access to feed and water
Bristol Gait Scoring System uses a 0-5 scale: 0 is normal, 3+ indicates significant pain
The EU Broiler Directive requires farms to take action when gait scores exceed thresholds
Fast-growing breeds (Ross 308, Cobb 500) have significantly higher leg problem rates than slower-growing breeds
Reducing growth rate by just 10-15% produces dramatically better leg health outcomes

Welfare Considerations

Leg disorders in broilers cause chronic pain in animals that must move on inadequate legs to reach food and water. A gait score of 3 indicates a bird that walks with clear difficulty and pain; scores of 4-5 represent birds unable to walk and who must crawl on their hocks. The birds at the bottom of the welfare scale are also the least able to access resources - they become progressively debilitated. The solution is well-established: breed selection for slower growth rates, reduced stocking density, better litter management and lighting programmes that allow adequate rest. These improvements require producer and retailer commitment to act on.

What You Can Do

Choose chicken from suppliers who have committed to the Better Chicken Commitment slow-growth standards
Ask retailers what maximum gait score they allow in their supply chains
Support Compassion in World Farming campaigns for breed welfare standards
Reduce chicken consumption as a direct response to leg welfare concerns
Support research into breed welfare assessment that includes locomotion quality