What is mud fever, and how do you prevent it?

Spring and autumn are seasons that offer a lot of color for us to enjoy out in the nature, but also a lot of changing weather where rain sadly is a big part of the everyday life. And with rain comes muddy fields. The risk of horses developing mud fever increases massively when the fields are muddy, and the following article will tell you more in-depth what it is and how to prevent it.

What is mud fever and what causes it?

Mud fever is a skin inflammation on the pastern of the horse which is caused by a wound infection. The skin on the pastern is thin and sensitive and if it’s not kept clean, small wounds easily appear.


The skin has a natural protection against unwanted organisms, but the protection can be weakened if the skin becomes moist and/or sore. The moist and damaged skin is easily infected by bacteria, as the skin on the pasterns is an extra sensitive area. The symptoms of mud fever are scabs on the pasterns, heat, tenderness, swelling and redness can occur. Aggressive mud fever can sometimes cause lameness. In some cases, mud fever can be caused by hypersensitivity reactions to, for example, sunlight or to the contents of certain plants out on the fields.

Consequences of mud fever

If the mud fever is not treated in time, it can spread. If it spreads upwards and affects the skin on the tendon the condition can get much worse. A common complication is lymphangitis (inflammation of the lymphatic vessels), which means that the lymphatic vessels in the horse's bones become inflamed. The lymphatic vessels normally transport fluid away from the tissues, but in the event of an inflammation in the lymphatic vessels, this does not happen. Then fluid accumulates in the horse's legs which swells sharply. The condition can become chronic if it is not treated in time, the horse then gets a so-called elephant bone.

How is the welfare of the horse affected?

It can go so far that the horse becomes lame from the mud fever, due to the fact that it causes pain and that the skin tightens from the swelling. As long as the horse is not hurting or showing lameness, it’s good if it’s allowed to move around as usual. If the horse is in pain and also is lame, it has gone so far that you should contact a veterinarian.

How do I prevent mud fever?

The most important thing is to always wash the legs after contact with mud or other dirt. While keeping the area nice and clean, you’re leaving an unfriendly environment for bacteria and fungus to thrive. Afterwards, make sure that you’re drying the legs, as we want all of the moisture gone. If the horse already has developed mud fever, be careful when drying with towels, as they can be a bit abrasive on the sensitive, and possibly wounded legs.


The horse’s hoof beard is there to protect from dirt and moisture and some horses have a lot of it, which gives them a bit more, natural protection. But many horse owners choose to trim the hoof beard however, due to practical reasons. When trimming the legs, it's especially crucial to clean and dry the legs after the horse has been out in the field or after a training session. So, either you leave the hoof beard to protect, or you cut it off and keep the area clean yourself. Whatever you choose, it is important to look after mud fever on the pasterns every day.


A great way of ensuring that the legs are drying efficiently after washing is to use a drying boot, which Siccaro has developed. It’s called Sahara Multi-Functional Boots and it has a fantastic ability to absorb the moisture and water from the fur and leave the legs dry after only 15 minutes. The boots can also be used for other purposes like for cooling, warming and for protection.

What does the vet do?

If the mud fever doesn't want to heal on your horse, it is important that you contact a veterinarian before it goes so far that the horse gets lymphangitis (inflammation of the lymph vessels in the legs that causes a severe swelling of the leg).

The veterinarian examines the horse and takes, if necessary, samples from the damaged skin for analysis. This is to try to get a better picture of the cause of the mud fever, which makes it easier to find the most effective treatment. If the horse has lymphangitis, the treatment is often supplemented with anti-inflammatory medication.

Change of routines if the horse has developed mud fever

When the horse has developed mud fever, it is important to eliminate the causes. If the horse once has had mud fever, it will unfortunately easily get it back.

  • Carefully inspect the legs every day.
  • Keep the fields/paddocks as mud-free as possible.
  • Wash and clean the legs after they’ve been in contact with mud or other dirt, e.g., salt from the roads.
  • Dry the legs after washing, to ensure that the moisture’s gone. One way to do this is by using the Sahara Multi-Functional Boots.
  • Ensure that the horse box is properly cleaned at least once a day.
  • Shop now