Mud Fever is a form of Pastern Dermatitis affecting the pastern and legs, and is sometimes interchangeably called Greasy Heel or Scratches. Most commonly this condition is referred to as Mud Fever when the symptoms expand from the heel and fetlock region up onto the cannon. Pastern Dermatitis is a skin infection that affects a horse’s legs. Despite the common name of Mud Fever, fever is not a common symptom but instead refers to the inflamed scabs that develop as a result of the disease. This disease can initially be only uncomfortable or irritating but then progresses to signs of lameness and severe sensitivity. In extreme cases, cellulitis can occur, which requires veterinary intervention.
Despite its name, it is not just mud that can create this problem. The primary cause of this form of Pastern Dermatitis is the damage to the skin barrier, which allows the penetration of bacteria (most commonly dermatophilus congelensis) or fungi into the layers of the skin, resulting in inflammation, swelling, oozing and the resulting scabs and hair loss.
Other cases of mud fever, which look very similar to the dermatitis caused by prolonged moisture and damaged skin barrier, include photosensitivity, allergic dermatitis, chorioptic mange (which damages the hair follicle and skin) and a less treatment-responsive condition called Chronic Progressive Lymphodema.
Horses that regularly chew or lick their pastern region, such as those with mites
Horses with feathers
Horses with non-pigmented skin
Horses that live in paddocks with areas that regularly become boggy or muddy including the arena (as soil and sand can both increase exposure to the bacteria and irritate any sensitive skin).
Provide the horse with an environment to keep the skin of the lower limbs dry, clean and protected from further abrasion.
Don’t apply anything to the skin that will further damage the skin surface, particularly the use of chemicals (sulfur products, methylated spirits, bleach, sump oil etc.).
The scabs harbour the bacteria. Soften all scabs with warm water and then remove. Take care to dispose of these scabs rather than to let them contaminate the environment.
For mild cases, apply a topical 2-3%chlorhexidine solution (do not scrub!) to the affected areas twice daily for a minimum of three weeks.
If the area is red or ulcerated, then a topical ointment will be soothing and protective.
If severe lesions are present or a poor response to “over the counter” topical treatment, then topical antibiotics will be required after consultation with your veterinary. Remember, most of the clinical signs associated with Mud Fever are the result of a secondary bacterial infection.
A veterinary consultation is required if there is any swelling of the limbs, and appropriate antibiotics may be prescribed. your vet may also prescribe anti-inflammatories which will also provide pain relief.
Treatment is required for a minimum of three weeks.
If there is limb swelling or lameness, Minimise sun exposure during the acute inflammatory stage.
Remove your horse from wet and muddy conditions.
Keeping stables and paddocks manure free.
Reducing access to mud.
Thoroughly wash and dry legs.
Consider clipping the hair on the legs.
Use creams or ointments regularly to create a barrier.
Inspect your horses’ legs, fetlocks and pasterns regularly during wet or dewy weather.
If you are uncertain whether your horse’s condition is Mud Fever, or are not seeing a positive response from the above treatment regime please consult with your veterinarian.