Lighting Programmes in Commercial Poultry: Welfare Implications of Light Management
Light management in poultry houses profoundly affects bird welfare, influencing sleep, behaviour, growth, and stress. Many commercial lighting programmes prioritise production over bird wellbeing, but evidence-based reforms are achievable.
Key Facts
Commercial broiler houses historically used near-continuous lighting (23L:1D) to maximise feed intake and growth — this severely disrupts sleep.
Chickens have a strong circadian rhythm requiring regular dark periods for sleep, immune function, and cardiovascular health.
Sleep deprivation in continuous light conditions increases leg weakness, sudden death syndrome, and ascites (fluid accumulation) in broilers.
EU regulations now require at least 6 hours of darkness per day for broilers, but enforcement and compliance vary.
Lighting intensity affects fearfulness — very low light reduces activity but increases fearfulness when birds are caught for slaughter.
Natural spectrum lighting (including UV wavelengths) improves chicken vision and allows more normal foraging and social behaviour.
Welfare Considerations
Lighting management illustrates how commercial optimisation for production metrics creates welfare problems that are invisible to consumers. Broilers kept under near-continuous light cannot sleep adequately — a basic physiological need. The cardiovascular and musculoskeletal consequences compound existing welfare problems from rapid growth genetics. Providing appropriate dark periods, adequate light intensity, and natural spectrum light costs relatively little but significantly improves chicken welfare. Welfare certification schemes that include lighting requirements are an important tool for consumers to identify better-managed flocks. The evidence base for welfare-positive lighting programmes is strong and the implementation barriers are low — making this a readily achievable reform.
What You Can Do
Choose chicken products certified to welfare standards specifying lighting requirements (minimum dark periods, adequate intensity).
Support the Better Chicken Commitment, which includes lighting standards as part of its welfare requirements.
Advocate for enforcement of existing EU minimum dark period regulations and equivalent standards in other jurisdictions.
Reduce chicken consumption — particularly from uncertified sources where lighting welfare standards are unknown.
Share information about the welfare importance of lighting management in poultry production with your network.