Aural Plaque in Horses
Also called aural papilloma, aural plaque is a condition affecting the inside of a horse’s ear. A white, plaque-like material, it sometimes appears thick and crusty. In most cases, there is tender pink skin underneath the plaque. This is usually a benign condition that does not bother the horse, but is purely a cosmetic issue. However, occasionally, a horse can develop ear sensitivity. Once aural plaque develops, it is tough to get rid of permanently.
Symptoms and Types
These are some signs that can be seen in the horse's inner ear:
- White, crusty plaque, usually raised and rough
- Thick, pink skin underneath lesions
If the horse has become sensitive to the lesions, there may be head shaking, head shyness, and the horse may be come difficult to put a halter or bridle on.
These plaques are thought to be caused by a wart-causing virus, such as papillomavirus, and spread by biting flies.
While it is easy for your veterinarian to diagnose aural plaque, most experienced horse owners can detect aural plaque, too, as the symptoms are quite obvious. During the summer months, the prevalence of small black biting flies make this an even larger issue, as they tend to aggravate the condition even more.
There is no definitive treatment for these plaques. As they are mostly a cosmetic issue, if they are not bothering the horse, no treatment needs to be pursued. However, if the horse has developed sensitive ears due to the plaques, certain treatments may be tried. The plaque can be removed and the pink skin underneath treated with a soothing, healing ointment. This usually reduces the size of the affected area and alleviates the pain. Anecdotally, a human immunomodulatory drug called Aldara can be applied as a cream to affected ears and has been reported to help.
For more difficult cases of aural plaque, you may want to consider giving your horse a pair of ear covers to wear outside. This protects from the irritating sting of the black flies, which can aggravate aural plaque and worsen the pain.
Living and Management
As papillomaviruses can become dormant in the body and never truly leave, once a horse develops aural plaque, it tends to come back eventually. Keeping the black flies from biting the inside of the horse’s ears is the best defense against the aural plaque becoming worse.