Horse Health: Dealing with Mud Fever

Wet winter and spring weather can lead to mud fever, also known as scratches.

Wet winter and spring weather brings inconvenience along with it. Besides slippery footing and messes everywhere, mud can cause a horse health problem commonly known as mud fever. Also known as scratches or pastern dermatitis, it causes irritation, painful sores, and scabs that when left untreated, can cause lameness. While mud fever usually affects only the pastern and heel areas, it can also spread up the legs, onto the belly, and in some cases, it moves up onto the neck area, where it’s known as rain scald. Now that you know a little more about what mud fever is, here are some tips for preventing and treating it.

What Causes Mud Fever in Horses?

Knowing what causes a problem is always a good first step in preventing and addressing it. Horses’ mud fever is caused by a bacterial infection, and it can be compounded by chorioptic mange mites. Under normal, dry circumstances, the horse’s skin does a good job of preventing microorganisms from making their way into the skin. But when dirt or even stable bedding constantly abrades a horse’s wet skin and that skin never has the opportunity to dry out, a breakdown of the protective barrier occurs, allowing bacteria to enter and cause infection.

As you may have guessed, mud fever thrives in muddy, wet paddocks. As it is a contagious condition, it tends to be more prevalent in areas where multiple horses congregate. And because unpigmented skin has less natural protection than darker skin does, horses with white socks tend to be affected more frequently than darker colored equines. This being said, mud fever is opportunistic; it will affect horses and ponies of every breed, color, and age.

Mud Fever Symptoms

It can be difficult to spot mud fever symptoms in wet, messy conditions, so take a little extra time to check your horse each day. The sooner you detect possible symptoms of mud fever, the more likely it is that you’ll have an easy time with treatment. Watch out for the following:

  • Swollen legs
  • Legs that appear to be tender or painful
  • Hair loss
  • Red, chapped skin
  • Open sores
  • Scabs

Pay close attention to your horse’s pasterns when looking for signs of mud fever. Symptoms usually show first as small, red ulcerations located in the plantar pastern region. The lesions typically grow larger, then develop scaling. Oozing, hair loss, and a noxious odor can develop, along with edema and skin fissures.

Preventing and Treating Mud Fever

Cleanliness is the first line of defense against mud fever. If possible, rotate paddocks/corrals so that horses are not forced to stand in wet, muddy areas. You can set up portable electric fencing to make this faster, easier, and more affordable.

Horses that spend time indoors should have clean, dry bedding such as wood shavings. Keep run-ins and stalls clean and dry, so skin has a chance to dry off completely instead of remaining constantly wet.

Groom your horse frequently – even if he’s only going to go out and get dirty again. This gives you a chance to spot mud fever symptoms before they have a chance to get out of control.

If you notice any mud fever symptoms, wash the affected area with an antibacterial solution, then dry them completely. Next, apply a barrier cream; there are several different ones to choose from. Anti-mud fever boots may also be used, if you like; just be sure that they do not encourage moisture retention.

If your attempts to get your horse’s mud fever under control don’t seem to be working, or if the condition appears to be worsening, have your vet visit right away.