Researchers found both steamed hay and haylage lowered horses’ exposure level to respirable dust particles compared to that experienced with dry hay. | Photo: The Horse Staff

Laurent L. Couëtil, DVM, PhD, professor of Large Animal Internal Medicine and director of Equine Research Programs and Equine Sports Medicine Center at Purdue University’s College of Veterinary Medicine in Indiana, presented data showing the benefits of avoiding dry hay in horses with mild airway inflammation, also known as equine asthma (EA), during the 2020 American Association of Equine Practitioners (AAEP) Convention, which is being held virtually.

“Poor performance with or without a cough together with excess tracheal mucus visible via endoscopy directly after exercise suggest the presence of mild EA,” he said. “A bronchoalveolar lavage (BAL, which involves introducing sterile fluid into a horse’s lung before drawing it back out again for testing) can confirm the presence of airway inflammation, and airway endoscopy can rule out other airway conditions such as infectious diseases, exercise-induced pulmonary hemorrhage, and upper airway obstructions.”

Identifying horses with mild EA allows appropriate management changes to eliminate poor performance associated with airway