Horse Mud Fever Welfare and Prevention

Mud fever — pastern dermatitis — causes painful skin infections in horses kept in wet conditions, and prevention through pasture management is far more effective than treatment.

Key Facts

Mud fever is caused by Dermatophilus congolensis and opportunistic bacteria that penetrate skin softened by chronic moisture
Heavy horses and horses with feathering are particularly susceptible due to moisture trapped against the skin by leg hair
The condition causes painful crusting and ulceration of the skin above the hoof, with lameness in severe cases
Horses with white legs may have photosensitization reactions that compound mud fever severity
Prevention focuses on reducing pasture mud through sacrifice paddocks, rubber matting, and rotational grazing
Treatment involves removing scabs — a painful process — and applying antimicrobial and barrier products
Dry housing during wet periods substantially reduces incidence in susceptible horses
Chronic mud fever can lead to lymphangitis — infection of the lymphatic system causing severe leg swelling

Welfare Considerations

Mud fever causes genuine skin pain that can significantly impair horse welfare during wet seasons, particularly in heavy horses whose feathering traps moisture. The treatment process — removing scabs to access infected tissue — is itself painful and requires care and sensitivity. Prevention through pasture management is overwhelmingly more effective and welfare-positive than treating established cases: keeping horses off deeply poached ground, providing field shelters, and using sacrifice paddocks during the wettest periods dramatically reduces incidence. Horses that develop chronic mud fever leading to lymphangitis experience severe welfare harm — painful leg swelling, reluctance to move, and potential long-term lymphatic damage. Early recognition and prompt treatment reduce these serious welfare consequences.

What You Can Do

Implement sacrifice paddock rotation during wet seasons to keep horses off deeply poached pasture
Inspect legs daily during wet periods, particularly in horses with white legs or heavy feathering
Keep affected legs dry — careful grooming, appropriate clipping, and barrier preparations reduce recurrence
Treat established mud fever promptly — remove scabs gently using warm water soaks before cleaning and treating
Provide field shelters that allow horses to stand on dry ground when conditions are wet
Consult a veterinarian for severe or lymphangitis-complicated cases requiring systemic antibiotic treatment