Mud Fever & Rain Scald

Presenting Signs

• Localised/ generalised hair loss or crusting of the skin
• May be itchy
• Lesions can be mildly painful
• Often follow period of wet weather, where horse may be standing in water or mud for prolonged periods
• Distribution/ location of lesions are often in areas subject to wet conditions: either rain, mud or sweat. (Can also be on head/ neck/ abdomen/ lower legs/ under tack)
• Rainscald: dorsal back
• Mud fever: distal limbs, particularly pastern area. White skin tends to be more commonly affected

Pathogenesis

• Caused by the bacterium Dermatophilus congolensis that lives in the environment. Requires abrasion to the skin and a moist environment to cause infection.
• Predisposing factors: muddy fields, sweating, pink skin, trauma to skin

Diagnosis

• A combination of client history, clinical signs, and sometimes diagnostic investigation if needed
• Clinical signs: matted hair, scabs, underlying yellow discharge, crusts may be dry in chronic or healing lesions
• In severe cases skin may crack, ooze and swell
• Confirmation of diagnosis: clinical signs, identification of organism with histopathology or cytology

Treatment

Clean and dry affected areas

• Heavily diluted hibiscrub or iodine solution
• Soak scabs gently to allow easy removal
• Avoid bandaging as creates a moist environment
• Dry well and keep clean

Stabling

• Allows dry environment, protects from rain and mud
• Protects from flies/ other biting insects which may cause skin abrasions
• Keep bedding dry and clean

Topical treatments for localised areas

• Crusts must be softened and gently lifted away to allow topical treatment to be applied directly onto the skin
• Daily for 5-7 days then weekly until resolved
• Seek appropriate medicated cream from your vets

Topical treatments for larger areas 

• Antibacterial shampoos and medicated creams from your vet work well
• Drying skin well is very important
• Avoid over treatment that could lead to further skin damage

Prevention

• Prevent excessive contact with rain/ mud and wet grass
• Ensure bedding is clean and dry
• Use individual rugs/ tack/ grooming kit to prevent cross contamination between horses
• Regularly check legs thoroughly, especially in feathered horses where skin lesions may be hidden
• Wash off/ groom well after exercise, to ensure no sweat is left in contact with the skin
• Put food and water on hard standing to minimise time spent standing in mud
• Keep feathers clipped

For more advice or if concerned, contact the team on 01323 815120.