Air quality in horse stables significantly affects respiratory health. Dust, mold spores, and ammonia from bedding and hay are primary drivers of equine respiratory disease.
Stable air quality is a welfare issue that operates largely below the threshold of obvious clinical signs. Sub-clinical airway inflammation from chronic dust and spore exposure causes exercise intolerance, reduced performance, and may contribute to the development of equine asthma in predisposed horses. Ammonia irritation affects mucous membranes and airways even when stable keepers cannot smell it. Good stable design — high ceilings, ridge ventilation, and minimal occupancy density — combined with low-dust bedding and high-quality forage or soaked/steamed hay significantly reduces respiratory welfare harm. These investments in air quality pay dividends across the lifetime of horses stabled in the facility.