With a few simple steps at the first signs of trouble you can keep this generally minor skin infection from growing out of control.
Often, the first signs of rainrot arise just hours after a horse is brought in from the rain: Tufts of hair begin to stand upright in patches over his back, sometimes following the contours of the “drip line” where water runs off of his body. Or the tufts might appear on the legs, where he has been wading in deep, wet grass. The areas with raised hair feel warm to the touch, and the horse may flinch from contact. By the next day painful, tight scabs will have formed over pockets of yellow-green pus.
Rainrot is an infection caused by Dermatophilus congolensis, which usually resides on the skin in a dormant state without causing trouble. However, persistent moisture can activate the bacteria, leading to infection. Advanced age, illness, stress, the administration of corticosteroids or other factors that can compromise immune function increase a horse’s susceptibility to rainrot.
Although it’s not the most serious skin infection a horse can contract, rainrot can cause discomfort and hair loss, so it’s good to get a developing case under control as quickly as possible.