Lighting conditions in poultry houses profoundly affect behavior, health, and welfare. Evidence-based lighting programs that provide appropriate day length, intensity, and spectrum significantly improve poultry welfare.
Lighting in poultry production has historically been managed to maximize production efficiency rather than welfare - low intensity to reduce activity and energy expenditure, continuous or near-continuous light to extend feeding time. Welfare science has demonstrated that these choices impose real costs on birds: suppression of natural behavioral repertoires, disruption of circadian rhythms, and reduced opportunities for normal activities. Regulatory requirements for minimum dark periods and light intensities in European production represent welfare gains hard-won through scientific advocacy. Further improvements - toward natural spectrum lighting, higher intensities, and natural light access - are achievable within commercial economics and represent the next frontier.