Horses can experience a variety of allergies from seasonal respiratory allergies to food allergies to skin reactive allergies. These reactions can range from mild and annoying to severe and concerning. Some of the most common allergens are:
- Dust, mold, and pollen
- Insect bites
- New or rarely fed substances
- Products applied to or touched by the horse
- Vaccines or drugs
Reactions to these allergens can appear in a few different ways and severity can vary:
- Swelling, redness, crusting at the reaction site
- Itching
- Hair loss
- Regional or body wide hives
- Labored breathing, coughing, or exercise intolerance in the case of respiratory allergies
Your veterinarian will consider a few different variables to narrow down the potential cause of a flair up. They will look at the horse’s living area; is it a barn with hay storage above stalls where dust can linger? Are they fed from a round bale that may be prone to developing mold in the center or at the bottom? How old is the horse? Does this horse have a history of seasonal reactions? Maybe they are allergic to a near by tree or flower or just the general pollen in the air. Where is the reaction occurring on the horse? Does it affect their breathing or is it a dermal (skin) reaction to something that was in contact with the horse’s body?
Thankfully, we have a couple of options for testing the cause of reactions. We can take a sample of the skin and submit it to be examined under a microscope to rule out other causes for reactions or we can take a blood sample and submit it for an allergy panel to detect specific allergen reactions.
Treatment and prevention will vary horse to horse, but some changes to environment and routine can help such as providing clean hay to prevent respiratory flair ups, using fly sheets and masks to help protect against bug bites, and bathing with medicated shampoos to soothe skin reactions. If your veterinarian determines medications are necessary, corticosteroids and antihistamines can help to keep reactions at bay. Custom formulated allergy shots are also available. They are tailored to each specific horses allergens and help their immune system fight against them.
Michigan Large Animal Associates, P.C. 