Respiratory health is fundamental to equine welfare and performance. Horses are obligate nasal breathers with a highly efficient but sensitive respiratory system. The stable environment, training demands, and dust exposure common in horse management all present respiratory welfare challenges that require proactive management.
Equine Asthma (formerly IAD/RAO/COPD/heaves) is an umbrella term for inflammatory airway disease ranging from mild (mild equine asthma, MEA) to severe (severe equine asthma, SEA). SEA is characterised by coughing, nasal discharge, exercise intolerance, and laboured breathing at rest. Equine Herpesvirus (EHV), Equine Influenza, Strangles (Streptococcus equi), and bacterial pneumonia are significant infectious respiratory conditions. Exercise-Induced Pulmonary Haemorrhage (EIPH) affects working horses, particularly racehorses.
The stable environment is the primary driver of equine asthma. Dust from hay, straw bedding, and arena surfaces contains fungal spores, bacteria, and particulates that trigger airway inflammation. Welfare-centred stable management includes: using dust-extracted or steamed hay (or replacing hay with haylage/soaked alternatives), using low-dust bedding (rubber matting, shredded paper, dust-extracted straw), ensuring good stable ventilation, avoiding dusty arenas, and maximising turnout time. Clean, fresh air is essential for respiratory health.
Signs of respiratory disease include: coughing (resting or exercise-induced), nasal discharge (clear, white, yellow, or blood-stained), increased respiratory rate or effort at rest, flared nostrils, reduced exercise tolerance, abnormal respiratory sounds (wheeze, whistle), and in severe cases, heaving breaths using abdominal muscles. Any persistent respiratory signs warrant veterinary assessment.
Diagnosis of equine asthma involves clinical examination, bronchoalveolar lavage (BAL) for cytology, endoscopy, and lung function tests. Treatment for equine asthma combines environmental modification (essential) with medications including inhaled or systemic corticosteroids to reduce airway inflammation and bronchodilators for relief of bronchoconstriction. Infectious respiratory conditions require appropriate antimicrobial or supportive treatment.
Respiratory conditions significantly impair performance and welfare simultaneously—horses in respiratory distress during exercise face genuine suffering. The relationship between training demands and respiratory health requires careful management; working horses with compromised respiratory function may experience exercise-induced suffering that is not immediately apparent to observers.
Biosecurity measures are essential for preventing spread of infectious respiratory disease. Isolation of new arrivals, vaccination against EHV and Equine Influenza, prompt identification and isolation of respiratory cases, and disinfection protocols protect both individual and herd respiratory welfare. Respiratory health monitoring should be integrated into routine health management programmes.