Equine asthma (formerly heaves or RAO) causes significant respiratory suffering in horses — air quality management and medical treatment substantially improve welfare outcomes.
Equine asthma welfare management requires equal attention to environmental modification and medical treatment. Horses managed medically without addressing the environmental trigger — dusty hay, deep straw bedding, poorly ventilated stabling — experience ongoing allergen exposure that maintains airway inflammation despite treatment. The welfare-optimal approach combines environmental dust elimination (soaked or steamed hay, paper or rubber mat bedding, maximized ventilation and turnout) with appropriate bronchodilator and anti-inflammatory medication. Horses with well-managed asthma achieve good respiratory welfare and maintain working capacity. Unmanaged equine asthma progresses to permanent structural airway changes and chronic respiratory distress — a preventable welfare deterioration.