Rain rot (dermatophilosis) is a bacterial skin infection causing painful crusting lesions in horses exposed to prolonged wet conditions, with prevention through shelter access being the most important welfare measure.
Rain rot causes painful skin lesions that may cover large areas of the horse's body. The scabs form when Dermatophilus bacteria infect waterlogged skin, and their removal during treatment causes significant discomfort. Horses with extensive rain rot may be reluctant to be touched or groomed in affected areas, showing pain responses to handling. The persistent wet conditions that cause rain rot also cause general discomfort and hypothermia risk. Prevention through ensuring horses have access to adequate shelter - often an underestimated welfare need - is far preferable to treating established infection.