06/22/2026
Equine asthma is a breathing problem caused by inflammation in the airways. It can range from mild to severe, but across all forms, one thing matters most: reducing dust and irritants in the horse's environment.
What many owners think of as "dust" is more than just visible dirt. It can include bacteria, mold and fungal spores, mites, endotoxins, and other tiny particles that trigger inflammation in the lungs. Some of the worst particles are actually too small to see.
The key is the horse's breathing zone - the air right around the nose. Dust in that area matters much more than dust elsewhere in the barn. Even a stable that looks clean can still have harmful tiny particles in the air.
Common dust and irritant sources can include:
• Hay
• Bedding
• Sweeping or mucking stalls
• Barn blowers
• Round bale feeding
• Very dry, windy conditions
• Pollens or other allergens
• Unusual triggers like nearby manure piles, chemical sprays, chickens, or certain bedding materials
Management often focuses on lowering dust exposure:
• Reconsidering hay and bedding
• Using wood shavings
• Feeding a pelleted diet or hay cubes
• Soaking hay
• Steaming hay correctly
• Considering haylage
• Avoiding round bale feeding in horses prone to severe asthma
Note that medication may help control inflammation or open the airways, but there is no replacement to environmental management. Long-term improvement depends on reducing dust in the horse's environment, especially in the breathing zone.
If you have questions or concerns about your specific equine, contact your veterinarian.
