Rain Rot in Horses: Welfare Management and Prevention

Rain rot (dermatophilosis) causes painful matted skin lesions in horses exposed to prolonged wet conditions, requiring prompt treatment and prevention.

Key Facts

• Rain rot is caused by Dermatophilus congolensis bacteria that penetrate rain-softened skin
• Classic signs are matted crusts that peel off with tufts of hair, leaving raw, painful skin underneath
• The back, hindquarters, and face are most commonly affected due to rain exposure patterns
• Immunocompromised horses and those with prolonged wet skin are most susceptible
• Treatment involves removal of crusts, topical antimicrobial washes, and dry shelter access

Welfare Considerations

Rain rot causes the welfare harms of painful skin lesions, the sensitivity of raw exposed skin to touch and grooming, and in severe cases, secondary bacterial infection and systemic illness. Affected horses may resist grooming and saddling due to pain, creating management difficulties. Welfare-focused management requires systematic crust removal (softening with antimicrobial shampoo first reduces pain), application of antibacterial topical treatments, and ensuring the horse has access to dry shelter. Prevention through adequate weatherproof shelter, turnout management during prolonged wet periods, and use of waterproof rugs when appropriate is the most welfare-effective approach.

What You Can Do

• Provide weatherproof shelter accessible at all times, especially during prolonged wet periods
• Soften crusts with dilute chlorhexidine or betadine shampoo before removal to minimize pain
• Use waterproof turnout rugs during persistent rain to prevent skin saturation
• Check horses daily during wet weather for early signs of skin lesions
• Consult a veterinarian for severe cases or those with systemic illness signs