Air quality in intensive pig facilities causes respiratory disease in pigs and workers, creating a welfare problem that links animal and human health.
Air quality in intensive pig facilities affects welfare through multiple pathways. Chronic ammonia exposure damages respiratory mucosa, increasing susceptibility to pneumonia that causes significant suffering. High particulate levels carry pathogens deep into respiratory tracts. Poor ventilation causes temperature extremes that add thermal stress. Respiratory disease is painful and, because pigs hide illness, often advanced before detection. Ventilation investment is a welfare investment with documented returns in reduced treatment costs and improved production.