Mud Fever
Equine Pastern Dermatitis (EPD) is a frustrating condition of horses that is known by many different names, including mud fever, mud rash, cracked heels and greasy heels. Many of us are familiar with milder forms of the condition that present as small scabs over the back of the pasterns and fetlocks; however the disease can worsen to large erosive lesions that cause significant distress to both the horse and owner as they are often very difficult to resolve.
The exact cause of EPD is not known and it is important to remember that the sores we see represent the end point of a number of different disease processes, one or more of which may be present in an individual.
It is generally agreed that at the point when they can first be detected, the skin sores are the result of infection by one or more types of bacteria (particularly Dermatophilus congolensis). Usually this bacteria is known as an ‘opportunistic’ pathogen, which means that there must be some underlying cause that allows the it to invade and grow within the horses skin.
Possible primary causes include:
- Mites - it is important to remember that these are almost never actually seen, but most horses will stamp their feet.
- Trauma such as scratches or cuts – stubbly pasture could be enough to trigger the condition
- Allergies – many systemic allergic skin diseases affect the same area and can cause only minimal effects themselves. Allergies can also occur at the skin surface to creams used to treat the EPD.
- Horse/environment factors – thick skin with deep creases, dense feathers and muddy or wet pasture all combine to create an environment the bacteria loves
Treatment is usually directed at killing the bacteria and the cleaning the lesions with hibiscrub and then blotting them dry with paper towel twice daily will usually do a good job of this; however if any underlying cause is not determined it is likely that the condition will recur, no matter how many different treatments or creams are used. Unfortunately it is often the horse/environment factors that are to blame and these can be tricky to manage, but a more thorough investigation and discussion will often yield some helpful results.
