Managing Mud Fever in Horses

During fall and winter, pastured horses are often exposed to moist, muddy areas. This can result in something called, "Mud fever," or "Pastern Dermatitis," an infection of the horse's legs. While mud fever can be troublesome, it is unlikely to be serious, though some horses take longer than others to recover from the lesions that can result. In this article, we will help you learn how to protect your horse’s legs and prevent mud fever from becoming a problem.

What is mud fever?

Wet ground can contribute to mud fever *

Mud fever is a common condition that affects horses throughout the globe when exposed to wet, muddy conditions. The skin over the pasterns and heels becomes inflamed, resulting in scabby lesions which can become infected and very painful. It is most commonly experienced by horses living in wetter climates, particularly those with white socks, stockings and limbs.

Treatment may involve the simultaneous use of an antibiotic, an anti-fungal, and a topical treatment. Speed of recognition is important in preventing spread or deeper infection. Call your veterinarian as soon as you suspect your horse may have mud fever to discuss treatment options.

Signs of mud fever:

  • Found on the lower limbs of the horse
  • Commonly seen on the back of the pastern and heels
  • Appears as crusty scabs in varying sizes from a mild infection up to irritation on all four legs spreading horizontally around the legs
  • The lesions leak a sticky serum which causes the hair in the area to mat
  • In severe cases, the back of the pastern can split open (cracked heels) which can lead to long term lameness

Causes of Mud Fever

Although the main contributing factor is damp, wet conditions, other factors can contribute to mud fever. Predisposing factors can include:

  • Genetic predisposition: Horses with white hair on the lower limbs and thicker coats or feathers appear to be far more prone to mud fever.
  • Environmental conditions - Anything that irritates, damages, softens, or causes a break in the skin will allow infection to occur, increasing the likelihood of mud fever.
  • Bacteria such as Dermatophilus congolensis and Staphylococcus spp. cause skin infection leading to mud fever
  • Other infections such as ringworm can damage the skin and allow secondary infection to occur.
  • Damage from boots which are too tight, trauma, sweating under boots during exercise, and contact from other horses can also leave legs susceptible to mud fever.

Managing Mud Fever

Although there are no 100% guarantees of preventing mud fever, you can take steps to control the likli-hood of your horse having to endure this unpleasant condition.

  • Ensure the horse spends some time each day on dry ground: this can be time in a stall overnight or during the day but keeping the legs and feet dry are essential to reducing problems with mud fever.
  • Ensure the stall environment is clean, dry, and ammonia free. Muck out daily and remove wet bedding as well as droppings, (See our article on effective mucking out.) Spalding Bye Bye Odor is ideal to use in the stall as it not only removes dangerous ammonia fumes from horse bedding but safely eradicates odor at its source.
  • Try to limit the amount of mud in your field, particularly around gates where horses may stand for long periods. (See our article on preparing for winter.) Ensure if you feed hay in the field that it is fed in different places each day and spread out. If possible, provide more than one place to drink.
  • Coat the legs with a barrier cream such as Zinc and Castor Oil prior to turning the horse out; this will keep the legs waterproofed.
  • If your horse is prone to severe mud fever, consider purchasing some special boots to protect the legs.

For more tips on winter and colder weather health care, come back to Morgan’s blog daily!

*Image courtesy of Dollar Photo Club