One of the things that many yards and horse owners struggle with each winter is Mud Fever.
Mud fever refers to a w ide range of equine skin reactions, which are primarily caused by an infectious agent called dermatophilus congolensis, which thrives in muddy wet conditions. It can also be referred to as pastern dermatitis, greasy heels or cracked heels and is frustratingly common in wet weather.
The infection can stay dormant in the skin, becoming active when the skin is compromised, usually by prolonged wetting. Spores germinate and produce hyphae (threadlike tentacles) that penetrate into the skin and spread in all directions from the original site. This causes an acute inflammatory reaction.
Equine skin provides an ideal environment for many bacterial organisms, as well as fungi and other parasites. These micro-organisms live on healthy skin, gaining nourishment from natural waste matter and causing no harm or active infection. But if the skin is damaged in any way by a cut or wound of some sort the balance of the host and organism is disturbed . The organism then enters the horses boy through the broken skin, and multiplies in the damp, warm epidermal layers, starting and active infection.
Some soil types seem to predispose horses to these infections. This may explain why several different horses that have been on the same land become affected. There are many different causes of Mud fever, some may include:
1. Prolonged damp or mild conditions
2. Standing in deep mud or soiled bedding
3. Constantly washing legs before and / or after work without fully drying them afterwards
4. Having lots of feather on the legs is frequently blamed but this is probably only because the legs tend to be washed and scrubbed more than horses with less or no feather. Clipping the feather off may not be the answer as this exposes the skin further
5. White legs or patches on the body possibly due to an associated photosensitisation issue.
Some horse with mud fever may also be suffering from infestations of tiny chorioptic mange mites, similar to those that cause scabies in humans. This is most common in horses with long hair around the lower leg, but can also be found in horses with less feather. The condition is often called heel mange. Fungal infections can also be responsible for skin damage.
The signs of mud fever are fairly classic and easy to recognise, with the scattering of the lesions reflecting the areas of the skin that have been subjected to continued wetting and / or trauma. Some of the other signs of mud fever could include:
1. Matted fur containing crusty scabs
2. Small, circular, ulcerated, moist lesions beneath the scabs.
3. Thick, creamy, white, yellow or greenish discharge between the skin and the scab.
4. In severe cases the skin at the bock of the horses leg may split open, producing the horizontal fissures that are characteristics of cracked heels.
5. Heat, swelling and pain on the pressure or flexion of the limb.
Keeping the skin clean and dry is the basis for treating mud fever. This may only be possible if the horse is removed for the wet and mud and kept stabled for a period of time. More specific treatment needs to penetrate the organisms under the scabs, so these must be removed to start with. Depending on the horse and the severity of the mud fever, the horse may need sedating as this can be painful. Some of the bigger scabs may need soaking to first soften them before they can be removed.
Once the scabs have all been removed, the area should be washed using a mild disinfectant such as an iodine wash, surgical scrub or medicated shampoo and then rinsed well.
Drying the leg thoroughly is vital. Clean towels or kitchen roll can be used to blot the moisture and a hairdryer is an excellent way of thoroughly drying the area. Once the area is dry there are many creams, lotions and gels on the market that may help. Bandaging the affected leg can also be a good way of keeping the leg clean and dry, but only if the skin has been prepared correctly beforehand. The whole process may need to be repeated several times and in severe cases a full recovery may take a few weeks. Antibiotics and anti-inflammatories will depend on the individual case but a vets advice should always be followed.