There it is again---that strange-looking bump, or scruffy patch, or bald spot on your horse's skin. It looks harmless, and it doesn’t bother your horse when you touch it. But it just won’t go away.
Is it something you can safely ignore, or do you need to treat it? The answer depends on whether the spot or bump in question is caused by a bacterial, fungal or viral infection, an insect bite, sunburn, allergic reaction, bruise, abrasion or any number of assaults the world can throw at a horse.
The good news, says William H. Miller, VMD, professor of dermatology at Cornell University, is that many equine skin diseases and conditions are not very serious. In fact, some issues are considered merely cosmetic and may be left untreated, and in many cases, a knowledgeable horse owner can safely handle the situation on their own.
But there’s a catch: In order to treat a condition effectively, you need to know for sure what it is, and some issues that stem from completely different causes can look remarkably similar. Just reaching for your favorite ointment and applying it to the skin can do more harm than good. Heavy salves like Vaseline, for example, can plug hair follicles, and many homemade remedies can irritate skin.
What’s more, says Miller, persistent skin problems are rarely just skin-deep. “Skin diseases can be indicative of a compromised immune system brought on by poor nutrition, age or other disease,” he explains. So no matter how basic your horse’s skin problem may seem, if it doesn’t respond to treatment or continues to recur, talk to your veterinarian. Not only can she confirm the identity of the issue, she will help you develop a treatment plan that may include dietary and management changes and possibly systemic drugs in addition to topical treatments. And in any case, if you’re unsure what you’re seeing or how to handle it,
it’s always best to consult with your veterinarian.
But if you’re looking at one of these eight common equine skin ailments, especially if you notice them early, you may be able to manage them safely on your own.
Rainrot (rain scald)
- Appearance: scabby crusts that form raised bumps with upright tufts of matted hair. The crusts form on
parts of the body that are chronically damp---often along the topline and where rain runs off down the barrel, shoulders or hindquarters, but also on the lower legs or faces of horses who regularly stand in mud or graze tall, wet grass. Over time, the crusts peel off, leaving small, round bare spots; pus may also be seen under newly sloughed scabs.
- Causes: Rainrot is a bacterial infection. The causative organism, Dermatophilus congolensis, can reside on the skin without causing trouble, but it multiplies rapidly in a moist environment. If the bacteria find a break in the skin, whether a small wound or insect bite, an active infection can develop. Anything that compromises a horse’s immunity---advanced age, malnutrition, illness---can make him more susceptible to the infection, as can having a heavy winter coat, which tends to trap moisture against the skin.
- Do I need to treat it? Yes. Rainrot is uncomfortable, if not painful, for the horse, and it can cause unsightly patches of hair loss.
- Treatment: First remove the horse from wet conditions and place him in a living arrangement where his coat can dry out thoroughly. A variety of anti-microbial shampoos and disinfectant rinses are available over-the-counter that are labeled for use on rainrot infections; the horse’s coat will probably need to be treated daily for at least a week. The specific duration of treatment depends on the product being used and the severity of the infection. Spot treating may be effective if only a small area is affected; otherwise, giving the horse a full bath may be advisable.
Picking off loose scabs may help them heal faster, because exposing the bacteria to air helps to kill them, plus it will enable topical treatments to penetrate further. But do not remove scabs if they are still tight and pulling on them causes the horse pain.
Call your veterinarian if an infection fails to improve after a week, despite treatment. She can make sure your horse actually has rainrot, rather than another similar condition, and may prescribe a topical medication or oral antibiotics, especially if a secondary infection has set in.
- Prevention: Provide dry areas that turned-out horses can retreat to in wet weather and keep your run-in shed’s roof in good shape. Waterproof blankets and light sheets can also help keep pastured horses dry; just make sure their coats are not damp when you put them on. Groom often, both to clear away mud or dirt, which can hold moisture against the skin, and to spot the infection in its earliest stages. Disinfect all blankets and equipment that came in contact with an infected horse before reuse.