Lighting conditions in poultry houses profoundly affect the health, behaviour, and welfare of farmed chickens. Evidence supports using natural light cycles and higher quality illumination.
Lighting is one of the most powerful environmental factors affecting poultry welfare, yet it has historically been managed primarily to maximise production rather than animal wellbeing. Chickens are diurnal animals with clear circadian rhythms that are disrupted by continuous or inappropriate lighting. The welfare consequences of poor lighting include sleep deprivation, impaired immune function, increased fearfulness, and higher rates of injurious pecking. Higher-welfare lighting programmes provide at least eight hours of darkness, appropriate intensity, and natural variation in light quality throughout the day. Natural daylight access significantly benefits both physical health and behavioural expression. Growing consumer and regulatory pressure is driving improvements in poultry lighting standards globally.