Mud Rash is a frustrating disease, caused by the bacteria, Dermatophilus congolensis, which is present normally on horses’ skin; it is a bacteria which has many similarities to a fungus. It causes scabs and matting of the hairs over the legs, especially lower legs, the fetlocks and pasterns (because they are the areas that get most exposed to mud!!! The bacteria can live in the soil for years and anytime your horse has a small defect in its skin it can penetrate it, multiply and set up an infection.
What will I see?
Mud rash is usually seen on the lower leg and your horse will have scabs and crusty exudates. If the infection gets established it may be very painful for your horse, its legs may swell and it may be lame. It is more commonly seen on horses with feathers and on white legs.
Horses with white socks seem to be more at risk, but all horses can get mud fever. Some horses appear to be lucky and are rarely affected by this condition. We are not entirely sure why but it may be skin immunity.
How can I treat my horse?
Prevention is better than having to treat but that is easier said than done!!
Hygiene is a very important factor, both in treating the horse and preventing horses from getting this condition. Wash horses legs off once they come in from the field. Dry the legs off as well. The bacteria grows best in damp, warm conditions.
If your horse has feathers unfortunately you need to trim them off. Clipping the legs off can help to allow drying time but it can be easier said than done when the scabs are very painful!!!
If your horse develops scabs, scrub the legs with warm water and a diluted antiseptic such as Hibiscrub, iodine or Malaseb (dog shampoo). Work it into a lather and then leave on for 10-15 minutes to allow contact time for the antiseptic to kill the bacteria. Sometimes you need to soak the leg to loosen the scabs. You MUST then dry the legs after cleaning the scabs off. Do this at least twice a day, or whenever the horse is exposed to muddy conditions.
Some cases have persistent scabs, just persevere and keep softening them with cleaning, warm water, creams or even zinc and castor oil.
Drying the legs off after bringing in from the field or after washing is very important. Using a dry towel or even a hair-dryer!!
Bandaging is not always the best solution as this can promote moistness although if the legs have been dried properly bandaging can be used to protect the legs and prevent swelling.
Barrier creams, such as udder cream, or flamazine (from your vet) are very useful as topical preparations. Apply after cleaning and drying the legs, not as a substitute for this.
How can I stop my horse from getting mud rash?
There are many preventative measures. Barrier creams or Vaseline may help to reduce or prevent mudrash. Bandages or “mud-chaps” can be put on in the field but care must be taken that they are dried daily and don’t rub the legs and make the skin irritation worse.
There are even powders that can be placed on the leg to act as a barrier as they turn to a protective gel. Many people still swear by the use of oils (vegetable or even pig oil!!!)
Lymphangitis and cellulitis (often called mud-fever when it cause a high temperature) are possible conditions that could occur if not treated and if the condition worsens.
Many cases require antibiotics and some require anti-inflammatories/painkillers.
Keeping horses in while they are suffering from mud rash may be beneficial. However, some horses’ legs swell up if kept in. For these horses, exercise at least twice a day before then cleaning up and drying them. Care must be taken if a sand arena is used as this can further irritate the legs!!
There are some other conditions that can appear similar to mudrash such as mite infestation (often occurs higher up the leg such as behind the knee and in feathered horses that may not have been turned out on wet fields; can be similar)
or pastern dermatitis from other causes so if you are struggling to completely cure a case of mudrash/fever despite carrying out the advice mentioned above, veterinary attention may be needed.
Rainscald is the same condition and is caused by the same bacterial infection. It is treated in exactly the same way although it is easier to stop water getting onto the skin by putting a rug on!!
If it is not clearing up with this basic advice then we may need to prescribe antibiotic cream to apply. Sometimes you may also need a course of antibiotics and anti-inflammatories. If in doubt, ring us for more advice.
Take home message
Keep your horses legs clean from mud on a daily basis and dry them carefully. Keep an eye out for any small scabs forming and keep on top of it!