Equine asthma encompasses a spectrum of chronic airway conditions from mild equine asthma to severe heaves (RAO), causing significant respiratory compromise and welfare impairment requiring environmental and medical management.
Equine asthma welfare impact depends critically on severity: mild equine asthma may cause subtle exercise intolerance and occasional coughing, while severe heaves creates visible respiratory distress at rest - standing with head low, elbows abducted, nostrils flaring, and using abdominal muscles to force air from lungs. The breathing effort of a horse in severe asthma crisis is physically exhausting and distressing. Environmental management is the cornerstone of treatment and prevention - removing the allergen source (dusty hay, mold spores in bedding) provides more sustained benefit than medication alone, because pharmaceutical management without addressing the trigger only provides temporary relief. Hay soaking, haylage or hay replacement, dust-extracted bedding, and maximum outdoor time all reduce allergen exposure. The condition is chronic and management is lifelong, requiring sustained owner commitment.