Common Skin Problems in HorsesBy Kentucky Equine Research Staff · August 10, 2015
That hairless patch of skin on your horse’s nose and the unpigmented skin underneath white hair serve as sentinels for the overall health of skin. Are these areas suddenly red and angry? Do they appear irritated or blistered? Worse, do they have open wounds or small areas of unhealthy skin? Or, worst of all, are they itchy or painful?
“Horses grazing for long periods under the intense sun are exposed to ultraviolet rays capable of causing sunburn, have access to a variety of weeds or chemicals that could be irritating to the skin as they nose around, and may be at risk for photosensitization,” describes Peter Huntington, B.V.Sc., M.A.C.V.Sc., director of nutrition at Kentucky Equine Research (Australia).
All three conditions can result in very mild changes to the skin, such as redness and inflammation, with only limited pain or itchiness. Severe cases of all three are equally similar, each potentially presenting with blisters, erosions, swelling, and bleeding. Severely affected horses show signs of pain and can be quite itchy. Further, as a result of rubbing and scratching, the primary lesion can often be masked, leaving behind only signs of self-trauma, making it even harder for an owner or handler to identify the inciting condition.
“Because there is no quick, easy, or accurate test to diagnose those three conditions, owners will need to do a little detective work to identify the cause of their horse’s skin woes,” advises Huntington. “This will involve scouring areas where the horse spends long periods of time looking for weeds, chemicals, or anything out of the ordinary and scrutinizing other horses on the farm to see if and where they too are affected.”
Eliminate the Sunburn Option
Avoiding sunburn is always a sound first step, and by eliminating sunburn as a possibility, only contact dermatitis and photosensitization are left as possible diagnoses. Sunblocks, reduced turnout, and the use of masks and sheets with ultraviolet ray protection are widely available and recommended.
Watch for Worrisome Weeds
If your fields are full of specific plants or weeds known to contribute to photosensitization, such as St. John's wort, buckwheat, clover, and spring parsley, controlled grazing using portable fencing or grazing muzzles might be indicated. Horses receiving certain medications such as phenothiazine, thiazides, sulfonamides (trimethoprim sulfa), and tetracycline are at a higher risk of photosensitization and might benefit from less exposure to the sun by turning out at dusk and dawn instead of high noon.
Consider Contact Irritants
Finally, consider contact irritants when conducting your investigation. Any chemical, fertilizer, or product can potentially cause irritation and damage to your horse’s skin. Examples include organophosphate pesticides, heavy metals, bedding, topical medications, soaps, shampoos, blankets, and wool.
“Ensuring a clean, safe environment for your horse and minimizing superfluous skin products are important factors for maximizing the health of equine skin, especially considering the integumentary system is the horse’s largest organ,” notes Huntington.
Skin Supplements for Maximal Health
Work with a veterinarian to determine the origin of any skin issues and the best course of treatment. In addition to veterinary intervention, nutritional supplements might be appropriate.
Kentucky Equine Research has developed several supplements that support a healthy integumentary system in horses, including the dual-action hoof, skin, mane, and tail supplement, Bio•Bloom PS (Bio-Bloom in Australia) and a long-chain omega-3 fatty acid product, EO•3.