Mud Fever in Horses: Signs, Causes and Remedies

Mud fever is one of those problems that many horse owners eventually encounter, particularly during a wet British winter.

Weeks of rain can turn gateways and paddocks into mud baths, and horses may spend hours standing in wet conditions. Unfortunately, that creates an ideal environment for problems with the skin on the lower legs.

After more than 30 years of owning and competing horses, I've experienced more than my fair share of muddy winters. Mud fever can sometimes begin as a relatively small patch of irritated skin, but it shouldn't simply be dismissed as an inevitable part of winter horse ownership.

Recognising the early signs and managing your horse's environment can make a considerable difference.

What Is Mud Fever in Horses?

Mud fever is a skin condition that usually affects the lower legs, particularly around the heels and pasterns.

You may also hear it called mud rash, greasy heel or cracked heel.

Wet conditions soften the skin, while mud and grit can cause tiny areas of damage. Once the skin's natural protective barrier has been compromised, bacteria can enter and infection and inflammation may develop.

Despite its name, mud itself isn't the only possible factor. Anything that damages or weakens the skin can potentially make a horse more susceptible.

Mud fever is generally considered non-contagious, so it doesn't normally spread directly from one horse to another.

What Does Mud Fever Look Like?

One of the most recognisable signs is the development of crusty scabs on the heels or lower legs.

You might also notice:

Red or inflamed skin

Matted hair

Areas of hair loss

Crusty or thickened patches of skin

Broken or sore skin beneath the hair

Heat or swelling in the lower leg

Discharge beneath or around the scabs

Tenderness when the area is touched

In more serious cases, the horse may become lame.

Mud fever can be uncomfortable and sometimes quite painful, so don't assume a horse is simply being difficult if they object to you examining the affected area.

Checking your horse's legs regularly makes it much easier to notice changes before they become severe.

What Causes Mud Fever?

Persistent wet and muddy conditions are one of the biggest risk factors.

When skin remains wet for long periods, it becomes softer and more vulnerable. Mud rubbing against that softened skin can create tiny areas of damage through which bacteria can enter.

But several other factors can contribute.

These include small wounds or abrasions, constantly wet bedding, repeatedly washing the legs without drying them properly, mites and other conditions that cause itching or skin damage.

Some horses appear considerably more prone to mud fever than others.

Horses with white legs may have more sensitive skin beneath those markings, while horses with fine skin can also be susceptible.

Horses with thick feathers aren't automatically protected either. Feathers can make it harder to see what's happening underneath, and conditions such as mites can cause itching and skin damage that increase the risk of secondary infection.

Why Is Mud Fever So Common During a British Winter?

The answer will be familiar to almost every UK horse owner: prolonged wet weather.

A field doesn't necessarily need to be completely waterlogged. Areas around gateways, water troughs, hay feeders and field entrances can become churned up very quickly because horses repeatedly stand and walk in the same places.

Once mud becomes deep, horses may have very little opportunity for their legs to dry properly.

That's why managing the environment can be just as important as anything you apply directly to the horse's legs.

Should You Wash Muddy Legs Every Day?

This is an area where horse owners often have very different routines.

It can be tempting to hose muddy legs every evening because they look cleaner afterwards. But repeatedly wetting the skin can contribute to the very conditions you're trying to avoid, particularly if the legs aren't thoroughly dried afterwards.

Where appropriate, allowing mud to dry and then gently brushing it away may be preferable to automatically washing the legs every day.

If you do need to wash the legs, make sure they're dried thoroughly afterwards with a clean towel.

What matters most is avoiding a cycle where the skin remains damp for prolonged periods.

How Is Mud Fever Treated?

If you suspect your horse has mud fever, particularly if the area is painful, swollen, spreading or causing lameness, speak to your vet.

Several different skin conditions can look similar, so obtaining the correct diagnosis matters.

Treatment will depend on the severity and underlying cause, but an important first step is usually getting the horse away from persistently wet and muddy conditions and allowing the skin to remain clean and dry.

Your vet may advise cleansing the affected area with an appropriate solution and may recommend additional treatment depending on what they find.

If the horse has particularly thick hair or feathers, careful clipping may sometimes be recommended to make the affected skin easier to examine and treat.

However, don't automatically clip sore or inflamed skin without considering how uncomfortable this could be for the horse.

Should You Remove Mud Fever Scabs?

This needs some care.

It used to be common practice to scrub or pick every scab away quite aggressively. That can be painful and may cause further damage to already inflamed skin.

Loose scabs may sometimes come away during appropriate treatment, but firmly attached scabs shouldn't simply be forcibly removed.

Follow your vet's advice, particularly if the area is extensive or painful.

The aim is to allow the skin to heal, not create additional trauma.

Can Barrier Cream Prevent Mud Fever?

Barrier creams are popular during wet weather and can be useful for some horses.

The principle is straightforward: they create a protective layer between the horse's skin and the wet, muddy environment.

However, they should be applied to clean, dry skin.

Putting a thick barrier product over damp, dirty skin can trap moisture and contamination underneath it, potentially creating exactly the sort of environment you're trying to prevent.

Barrier products also shouldn't be regarded as a substitute for good field and skin management.

How Can You Prevent Mud Fever?

You may not be able to eliminate mud from a British winter, but you can reduce some of the factors that make mud fever more likely.

Try to avoid leaving horses standing in deep mud for prolonged periods where possible.

Pay particular attention to high-traffic areas such as gateways, troughs and feeders. Rotating fields, moving feeders, fencing off badly poached areas or improving the surface around gateways can all help where facilities allow.

Give your horse access to somewhere dry to stand for at least part of the day.

Check the legs regularly so that you notice early changes.

Avoid unnecessary repeated washing, and thoroughly dry the legs when washing is necessary.

Keep stables and bedding clean and dry.

Deal promptly with cuts, abrasions or other skin problems.

And if your horse has mites or another condition that causes persistent itching, speak to your vet about treating the underlying problem.

Should You Use Turnout Boots to Prevent Mud Fever?

Turnout boots designed to keep mud away from the lower legs are another option some owners consider.

They can work well for certain horses, but fit and management are important.

Poorly fitting boots can rub, while moisture or dirt trapped underneath them may cause additional skin irritation.

If you use turnout boots, remove them regularly and check both the boots and your horse's legs carefully.

Don't assume that because the legs are covered they no longer need checking.

Are Horses with Feathers More Likely to Get Mud Fever?

Heavy feathering can be both helpful and problematic.

Feathers provide some natural protection, and routinely removing them from a healthy horse isn't necessarily required.

However, thick hair can make early skin changes harder to see and can retain moisture close to the skin.

Feathered horses can also be affected by mites, which may cause intense itching. Scratching and stamping can damage the skin and potentially create an opportunity for secondary infection.

If your horse has feathers, regularly feel through them rather than relying entirely on what you can see from the outside.

When Should You Call the Vet About Mud Fever?

I'd err on the side of seeking veterinary advice rather than allowing a significant skin problem to continue untreated.

Contact your vet if you notice substantial swelling, heat, pain, discharge or lameness, if the condition is spreading, or if your horse is reluctant to let you touch the affected area.

You should also seek advice if what appears to be mild mud fever isn't improving.

Severe infections can occasionally lead to more serious complications involving the lower leg, so significant swelling shouldn't be ignored.

Persistent or recurring mud fever can also sometimes indicate that there is another underlying issue that needs investigating.

Is Mud Fever the Same as Rain Scald?

They are related skin conditions and can involve the same type of bacteria, but they usually affect different areas of the horse.

Mud fever is typically associated with the lower legs.

Rain scald usually affects areas such as the back, neck and hindquarters and is associated with prolonged wetting of the coat and skin.

If you're unsure which condition your horse has, ask your vet rather than trying to diagnose it from photographs online.

Mud Fever and Winter Horse Management

Preventing mud fever isn't really about finding one miracle cream.

It's part of good overall winter management.

Turnout, field drainage, clean bedding, regular leg checks, appropriate grooming and giving horses opportunities to dry out can all play a part.

We've covered these wider considerations in our guide to Preparing Your Horse for Winter in the UK.

If your horse is clipped during winter, you may also find our Horse Clipping Guide useful when deciding how much coat to remove according to workload and management.

Frequently Asked Questions About Mud Fever

Is mud fever contagious?

Mud fever is generally considered a non-contagious skin condition, so it doesn't normally spread directly between horses or from horses to people.

Can horses get mud fever without being in mud?

Yes. Persistent wetness and damage to the skin are important factors, so a horse doesn't necessarily have to be standing in a muddy field to develop a similar problem.

Should I pick the scabs off mud fever?

Don't forcibly remove firmly attached scabs. This can be painful and may further damage the skin. Follow your vet's treatment advice, particularly if the area is extensive or sore.

Should I wash mud off my horse's legs every day?

Not necessarily. Repeated washing can keep the skin wet. In some circumstances it may be better to let the mud dry and gently brush it away. If you do wash the legs, dry them thoroughly afterwards.

Can I turn a horse out with mud fever?

This depends on the severity of the condition and the turnout environment. Persistently exposing affected skin to deep wet mud can make healing more difficult. Ask your vet about the most appropriate management for your horse.

Does mud fever go away on its own?

Mild skin irritation may improve when conditions change, but don't assume established mud fever will simply disappear. If you suspect mud fever, particularly where there is pain, swelling, discharge or lameness, seek veterinary advice.

Prevention Is Better Than Fighting It All Winter

Mud fever can be frustrating because once the skin becomes damaged, continually turning the horse back into wet, muddy conditions can make recovery more difficult.

The best approach is to think about prevention before the fields become completely waterlogged.

Look at where your horse spends most of their time, pay attention to gateways and feeding areas, check their legs regularly and try to give them opportunities to stand somewhere dry.

Most importantly, don't ignore early signs.

A few small scabs or a little soreness are much easier to address than a painful, swollen leg several weeks later.

British winters will probably always bring mud.

The aim isn't to keep your horse perfectly spotless. It's to protect the skin as much as reasonably possible, notice problems early and get appropriate veterinary advice when something doesn't look right.

"This article represents the personal views and opinions of the author and should not be taken as representative of the official policy or position of any organization, professional, expert, or individual."