Natural light provision in broiler housing improves welfare by supporting normal circadian rhythms, enabling natural behavior patterns, and reducing the chronic low-level stress associated with constant artificial lighting.
Broiler lighting welfare illustrates how production optimization can impose chronic physiological costs on animals without obvious acute harm. Extended lighting regimes that maximize feeding time disrupt circadian biology in ways that compound the leg and cardiovascular problems already associated with rapid growth genetics. The dark period requirement is a simple, low-cost intervention with measurable welfare benefit. Consumer certification programs that require minimum dark periods, circadian lighting management, and natural light access are implementing welfare improvements that have strong evidence bases and are achievable at minimal cost across production systems.