## Overview Recurrent airway obstruction, also called heaves or severe equine asthma, is a chronic allergic airway disease similar to human asthma. Exposure to dust and mold in hay and bedding causes airway inflammation and constriction. Signs include chronic cough, nasal discharge, increased respiratory effort, and in advanced cases a heave line from abdominal muscle hypertrophy. Average age of onset is around 9 years. ## Causes Hypersensitivity to organic dusts, especially in hay. ## Diagnosis Clinical signs, endoscopy, and bronchoalveolar lavage. Response to environmental change supports the diagnosis. ## Treatment Environmental management is essential (pasture turnout, soaked or steamed hay, dust-free bedding). Corticosteroids and bronchodilators control inflammation and spasm. ## Recovery and Prognosis Lifelong but manageable. Clinical signs can be well controlled with strict environmental changes. ## Prevention Minimize dust and mold exposure, especially for susceptible horses.
chronic cough; nasal discharge; increased respiratory effort; heave line in advanced cases
## Overview Recurrent airway obstruction, also called heaves or severe equine asthma, is a chronic allergic airway disease similar to human asthma. Exposure to dust and mold in hay and bedding causes airway inflammation and constriction. Signs include chronic cough, nasal discharge, increased respiratory effort, and in advanced cases a heave line from abdominal muscle hypertrophy. Average age of onset is around 9 years. ## Causes Hypersensitivity to organic dusts, especially in hay. ## Diagnosis Clinical signs, endoscopy, and bronchoalveolar lavage. Response to environmental change supports the diagnosis. ## Treatment Environmental management is essential (pasture turnout, soaked or steamed hay, dust-free bedding). Corticosteroids and bronchodilators control inflammation and spasm. ## Recovery and Prognosis Lifelong but manageable. Clinical signs can be well controlled with strict environmental changes. ## Prevention Minimize dust and mold exposure, especially for susceptible horses.
chronic cough; nasal discharge; increased respiratory effort; heave line in advanced cases