Broiler Chicken Lighting and Sleep Welfare

Lighting regimes in broiler production directly affect sleep, circadian rhythms, and welfare. Evidence strongly supports minimum dark periods as a welfare requirement for commercial poultry.

Key Facts

Standard commercial broiler lighting often provides less than 4 hours of darkness in a 24-hour period
Insufficient darkness disrupts circadian rhythms and impairs immune function in broiler chickens
Minimum 6-hour dark periods are required by RSPCA Assured certification and are the subject of EU legislative proposals
Chickens in continuous or near-continuous light show higher rates of eye abnormalities and immunosuppression
Appropriate darkness also reduces mortality rates by allowing adequate rest and reducing activity-related cardiac stress

Welfare Considerations

Lighting management in broiler production has direct welfare implications that are well-supported by evidence. Continuous or near-continuous lighting was introduced to maximise feed intake and growth rate, but at the cost of sleep disruption, immune impairment, and eye damage. Minimum dark periods of 6-8 hours are achievable without significant production penalties and are increasingly required by welfare certification schemes. This is an area where regulatory standardisation would rapidly improve welfare across the sector, as the evidence base is clear and the cost of compliance is modest.

What You Can Do

Choose chicken certified by schemes requiring minimum dark periods such as RSPCA Assured
Advocate for minimum lighting standards in commercial poultry welfare regulations
Support research into optimal light-dark cycles that balance welfare with production requirements
Raise lighting welfare as an issue with supermarkets and food service companies when discussing chicken sourcing