Lighting Programmes for Laying Hens: Welfare Implications

Lighting management profoundly affects the biological rhythms, behaviour, and welfare of laying hens in commercial production.

Key Facts

Commercial egg production uses controlled lighting to stimulate and sustain egg production year-round
Continuous or near-continuous lighting (23 hours per day) was historically common but is now largely banned in the EU
EU regulations require at least 8 hours of darkness per 24-hour period for laying hens
Insufficient darkness disrupts circadian rhythms, suppresses immune function, and increases mortality from ascites
Dim red lighting reduces feather pecking by lowering visibility of wounds but also limits natural behaviour expression
Natural light access in free-range systems correlates with better bone strength and activity levels
Hens prefer light levels between 5 and 20 lux for resting, higher for foraging — most sheds use fixed low levels
Intermittent lighting programmes that mimic natural day length improve welfare with no loss in production

Welfare Considerations

Lighting is a powerful but frequently underappreciated welfare lever in laying hen production. Manipulating photoperiod for production purposes — extending "day" with artificial light — comes at a welfare cost when darkness and circadian rest are insufficient. Sleep deprivation and disrupted biological rhythms impair immune competence, bone health, and behavioural expression. Welfare-progressive facilities are adopting naturalistic lighting programmes that provide genuine darkness periods, graduated light transitions that mimic dawn and dusk, and species-appropriate light intensity variation throughout the day. These modifications show welfare benefits with minimal production impact, making them a cost-effective welfare investment.

What You Can Do

Advocate for minimum darkness period requirements in egg production regulations
Support producers certified to welfare standards requiring naturalistic lighting programmes
Ask your egg retailer what lighting standards their suppliers are required to meet
Fund research into optimal lighting for laying hen welfare across different housing systems
Push for regulatory review of lighting standards in broiler production, which lags behind layer standards
Choose free-range eggs where hens have access to natural daylight when possible