By Heidi Swiderek

When a horse shows signs of illness or lameness, the cause is not always clear-cut. I learned this the hard way when my 14-year-old Haflinger gelding, Brody, battled a rare condition last year. Along the way, however, I discovered the power of working closely with a good veterinarian, doing my research, taking notes, and not giving up. I’m sharing this experience in hopes it can help another horse owner struggling with a difficult diagnosis.

In September 2010, after moving to a new barn, Brody developed a swollen sheath and severe hives primarily around his hind legs, rump, and sheath. After a day or two of cold water soaks and cleaning with no improvement, I called my veterinarian. We agreed the sudden swelling and hives seemed like an allergic reaction, and the fact he was at a new barn supported that possibility. My vet began treating Brody with the corticosteroid prednisone as we tried diligently to determine the cause. It helped reduce the swelling and hives, but once we lowered the dosage he would flare back up, often worse than before.

By the end of October, I moved Brody back to his previous, familiar environment, but he did not improve. My vet suggested allergy testing, and I was anxious to finally find out what was causing Brody’s reactions. Brody tested borderline to positive for 42 items. It seemed unbelievable that he could suddenly be allergic to so many things, but my vet explained allergies can develop at different stages in life and recommended allergy desensitization shots.

The allergy desensitization serums were unique to Brody’s case, based on his various allergies. However, by