Disease is a major welfare challenge in broiler and layer hen production. High stocking densities and genetic factors create conditions where infectious disease causes widespread suffering.
Disease welfare in poultry encompasses both the suffering of individual birds experiencing infection and the mass culling events used to control disease spread. Individual birds with respiratory disease experience breathing difficulty, lethargy, and pain. Mass culling through methods including CO2 exposure and whole-house gassing raises welfare concerns about the speed and humaneness of death at scale. Prevention through reduced stocking densities, good ventilation, litter management, and biosecurity reduces both disease incidence and the welfare costs it imposes. Consumer demand for higher-welfare poultry products from farms with better biosecurity and lower stocking densities creates market incentives for disease prevention investment.