AN UNUSUAL CASE OF LYME DISEASE
False leads, shifting signs and unexpected test results complicate the search for answers about a gelding’s persistent headshaking.
Early one spring, several years ago, I got “that call” from the barn that so many horse owners dread: Something was wrong with my beloved horse, a handsome Thoroughbred named Whisper.
Whisper was 9 years old then, and I’d had him for nearly four years. At first, I had taken him in only to foster him for CANTER, the national nonprofit organization that helps find new homes for retiring racehorses. But I quickly fell in love with his friendly, laid-back, puppy-like personality. I ended up adopting him even though I knew he’d be able to handle only light work due to a fetlock injury and the arthritis that was likely to develop as a result. Still, I was able to do some dressage and trail riding with him.
At the time I’d received that call, the pain in Whisper’s fetlock had been acting up, and he’d been in his stall off and on for a few weeks, with limited turnout. The situation was difficult, but it was about to get much more complicated.
Whisper had begun shaking his head, flipping it up and down almost frantically. It was so persistent that he wasn’t even stopping to eat. At first the staff thought he might have developed the repetitive movement because he was bored in his stall, so they moved him to a small paddock, but he continued to shake and flip his head.
When I arrived at the barn, he was standing in the corner of the field, tossing his head up and down rhythmically, while occasionally flipping his nose in the air as if he was being bitten or shocked.
He looked confused, agitated and miserable.
After a close examination, my veterinarian said he thought Whisper’s head flipping was probably due to ear mites, and he prescribed a medication to put in the gelding’s ears twice a day for a week. But the headshaking did not stop. What’s more, Whisper developed a swelling under his jaw.
After a new examination, my veterinarian decided Whisper’s issue might stem from some type of infection, unrelated to his ears. Although he had been immunized against strangles, and he had no fever or nasal discharge, the lump under his jaw was suspicious. The veterinarian prescribed an antibiotic and anti-inflammatory medication for the pain and told me my horse should be feeling better in a few days.
To my great relief, Whisper did improve. He began eating again, the lump diminished and he appeared to be more relaxed. Still, I dove into a search for any information I could find on headshaking.
But the more I read, the more confused I seemed to get. This syndrome, in which a horse will constantly flip his nose and jerk his head, can have many causes and potential treatments. Triggers for the behavior can include exposure to bright sunlight, exercise, loud sounds, smells or allergies. In some horses, the behavior is limited to the spring and summer, while in others it can occur year-round. Often, headshaking can result from a malfunction of the trigeminal nerve, a sensory nerve in