If you find small, white, crusty spots in your horse’s ears, resist the urge to pick or scrape them off. These wart-like growths are nothing to worry about and your efforts to remove them are likely to do more harm than good.
The growths are most likely aural plaques, also known as papillary acanthoma or ear papillomas. They are caused by one of several strains of papilloma virus spread by flies. Typically, both ears are affected, and while the pale, crusty patches may look unpleasant, they usually don’t cause the horse discomfort.
On the other hand, attempts to scrape away these crusts will likely be painful for your horse and may end up making him head shy. What’s more, if you manage to remove the plaques, they will probably just return.
If, however, the plaques crack and bleed, or if they seem to bother your horse, ask your veterinarian how the situation can be managed. Fitting your horse with ear covers when insects are most active may prevent the spread of plaques and keep them from becoming irritated. In addition, covering the growths with soothing cream, such as zinc oxide, may reduce discomfort. Your veterinarian may recommend using the topical immune-modulating medication imiquimod, but this treatment protocol is labor-intensive and expensive, so it’s typically reserved for extreme cases.
This article first appeared in EQUUS issue #464, May 2016.