Rain Scald is a skin infection seen in horses and ponies kept at grass. The most commonly affected areas are the back, loins, quarters and shoulders. Large tufts of hair become matted together and these can be gently teased off with a thick crust of exudate. The underlying skin may be dry and flaky or it may exude serum. Sometimes a secondary infection is present and a thick layer of pus can be found under the scabs.
Exposure to prolonged rain leads to excessive wetting of the skin. Bacteria is able to penetrate the softened skin and cause an exudative dermatitis.
To treat Rain Scald, firstly stable the horse until the lesions have healed as it is very difficult to clear the infection if the horse is still exposed to rain. Gently remove the scabs, if they are small and widespread a fine toothed comb removes them effectively. If there is exudate under large scabs, clean the skin with an anti-bacterial wash. Keep the horse stabled until the skin is dry and healthy.
In severe cases call your vet as they may prescribe a course of antibiotics.
To prevent Rain Scald, provide a field shelter for your horse and use a New Zealand rug.