Natural Horse World

Mud Fever/Greasy Heel Treatment Tips

Mud Fever Greasy Heel
Mud Fever or Greasy Heel can start with just a few ‘scratches’ like this and when caught early has the best chance of healing quickly.

Mud Fever or greasy heel affects the lower limbs of our equine friends and may cause pain and swelling that is
accompanied with crusty scabs of varying sizes. In serious cases, the horse may become lame and the whole leg seriously swollen and infected.

Mud fever was thought to be caused by a bacteria that thrives in warm, moist conditions. However, My experience (over many years of adjusting my horse’s diet and living conditions) has shown me that it usually happens when a horse has inadequate minerals in their diet, especially copper and zinc.
And when there are toxins/high levels of sugars in the grass they can cause an inflammatory reaction in the legs.
Moisture and sun sensitivity then make this a painful condition that takes commitment and dietary changes to overcome quickly.


  1. Remove the horse from the pasture to an area where there is little grass and feed free choice low-sugar grass hay in a slowfeeder hay net. Feed extra copper/zinc available in a balanced formula (available from the
  2. To help remove the scabs cover them with Vaseline and use cling film under a cohesive bandage to wrap the affected area overnight. This allows the scabs to be removed easily.

    Greasy Heel or Mud fever swelling
    Greasy Heel or Mud fever sometimes involves swelling in the early stages.
  3. Apply an ointment such as a mix of Filtabac and vaseline or Filtabac and Derisal (cow udder ointment). The Filtabac helps with keeping the sun off.
  4. If the condition is acute, ie; legs very swollen, horse very lame/sore, a steroidal cream (Prednoderm) or antibiotics may be needed to start with. If you’re unsure about your horse’s condition, call your vet.
  5. Continue daily treatment with ointment and additional scab removal if needed until under control (usually about a week).
  6. Protecting your horse from mud, and flies while treating mud fever or rain scald will be of great benefit to the recovery process.
  7. A 3-day course of Arnica/Ignatia/Hypericum from your Homeopathy First Aid kit would be a good idea!

by Paul & Karen Lockwood
We were first introduced to Pat Coleby’s book “Natural Horse Care” by a neighbour back in about ’96. We thought it sounded pretty good & started to base our supplemental feeding on her ideas. The ponies we had did just fine on this feed with the grazing they had & the addition of hay in winter.
Then we got Jacko, a severely undernourished 3-year-old first cross-quarter horse.

Jacko1So we started the task of putting some weight on him, wow could he eat. It didn’t seem to matter how much we fed him, he didn’t put on weight. After six months he started to get greasy heal on 1 of his 3 white feet so we treated it topically with iodine which at first appeared to work. Then the greasy heal started to appear on his 2 other white legs as well, treatment with iodine did not seem to work at all, the scabs started to grow in size & number & spreading up his white socks. Mud Fever?

Over the following 6 months we tried every topical remedy that anyone told us about, Vaseline, White Healer, engine oil & Quit itch (iodine). They all seemed to do something at first, then the mud fever would come back even worse.

What a nightmare, he started to become lame with the condition. Then we remembered Pat Coleby had remedies in her book! Jacko was copper deficient! The answer was on our shelf all the time – why hadn’t we used it? A copper sulfate wash for his legs and feed him copper sulfate to address his deficiency.

Oh, that’s right we looked at the packet of copper sulfate at the hardware store, saw the poison label, did the human thing & asked around about copper sulfate & feeding it to horses & came to the conclusion that it might kill him. He should be getting enough copper from the seaweed. Wrong.

Well, we didn’t seem to have any other choice & to make matters worse 1 of our other horses started to get greasy heal, so we purchased the copper sulfate & just washed their legs with it. Hmm! Didn’t seem to be doing much after a week or so, looked like we had to feed the copper sulfate.

Jacko was the guinea pig, we started with a ¼ teaspoon daily in his feed. He didn’t seem to mind it at all & so increased it to ½ teaspoon. Within 1 week the mud fever had started to recede, yippee!!! After 2 weeks it had halved & 1 month later completely cleared. In the meantime we decided to feed ¼ teaspoon copper sulfate to the other horse, he didn’t like it at all.

What now? He would not eat a feed with copper sulfate in it until we reduced the amount to 2 tiny grains!! That’s not enough. We then doubled the amount on a daily basis until we reached a ¼ teaspoon. After a week or so of the ¼ teaspoon, his greasy heal had gone. So not only did it not kill them, it cured them. Phew!! Over the next year or so Jacko changed colour from washed out orange to a shiny copper chestnut.


We became more aware of what Pat Coleby was saying in her book. We even wrote to her to tell her the story. She wrote back suggesting her new version of the book would be interesting reading. We purchased that & another of her books Natural Farming & Land Care. Both well worth getting, the amounts of copper sulfate & sulfur had been increased from the early version.

When we increased the sulfur to 1 tablespoon for Jacko he started to absorb his feed properly & finally started to put on weight to the stage where we reduced his feed to less than half what we had previously fed. We also had a soil test done which confirmed our pasture was, in fact, low in Calcium, magnesium, sulfur, copper, zinc & boron. Surprise, surprise!!

We have top dressed our paddocks as recommended by the soil lab over the past 2 ½ years and decided that we could stop the feed supplementing of minerals as we had them available in an ad lib form, as described in Pat Coleby’s books, as well as ad-lib seaweed and ad lib rock salt.
After 2 weeks, in January this year, of not supplementing their feed the greasy heal returned, 2 years after we thought we would never see it again, even though we had observed them using the ad lib minerals, & seaweed, they did not take enough.

We returned to supplementing on a daily basis, 1 tablespoon Dolomite, 1 tablespoon powdered sulfur, ½ teaspoon copper sulfate for Jacko (¼ for Spike) & 1 teaspoon of seaweed meal as our maintenance ration, they still take more from the ad lib options as well. The Greasy heal cleared in 2 weeks. Looks like our horses need copper more than we think?
We thoroughly recommend you at least read one of these books before using the information, to get a better understanding of the importance of minerals in your horses’ diet and the soil your feed is grown on so that you can tailor your supplement to suit your individual horse’s needs. You will also find in both these books a list of common conditions & which mineral deficiency is the underlying cause.

4 thoughts on “Mud Fever/Greasy Heel Treatment Tips”

  1. Kaye Walker

    Dear Cynthia,
    Thank you for the mud fever story and reminder to consult my Pat Coleby “Natural Horse Care” book. In it she discusses the use of Vit C (sodium ascorbate) for sick horses. My horses – one with mud fever, one with dermatitis and one I think just resisting all after moving to a new property, but managing to rip his mouth and face in the new stall latch. Pat doesn’t really suggest any specific amounts of the sodium ascorbate to add to their feed daily – do you have any recommendations?
    I’m getting the soil tested tomorrow and after no management for several years with intense fertilisation prior to that I’m banking on needing mineral repatriation. So I am adding all Pat’s and your recommendations for a daily regime of dolomite, sulfur, copper sulfate and seaweed meal at present, and have added turmeric to the list.
    Thank you for your consideration, and your website.

    1. Cynthia

      Hi Kaye,
      Generally, only older or really sick horses need vitamin C as they manufacture their own when healthy. Dr Juliet Getty has some good info here: but you will probably find when you get the minerals balanced (esp. copper and zinc) then your wiill resolve the mud fever and dermatitis. The Balanced equine mineral mixes provide the correct ratio and balance of these minerals so I would recommend those over the Pat Coleby approach.
      Hope this helps and good to hear you’re addressing the soil health too 🙂
      Cheers, Cynthia.

  2. Jan Kirkpatrick

    Would you please advise me on how to make a Copper Sulfate 30% solution to treat my horse’s scratches (Mud fever)?

    In one litre of water, how much copper sulfate powder would create a 30% solution?

    I read in ‘Natural Horse Care” to use a 30% solution. It does not, however, explain how to make it.

    I’ve been going crazy trying to figure it out online.

    Thanks you

    Jan Kirkpatrick
    Calgary, Alberta, Canada

    1. Cynthia

      Hi Jan, I generally make a mixture of copper sulphate (1 teaspoon) with petroleum jelly/vaseline (1 cup) but if you wanted to wash with a solution then use the same amounts with copper and water. I think the vaseline mix works better because it softens the scabs when left on for 24 hours, especially if you wrap the legs with plastic under a bandage. I hope that helps, and remember if your horse has scratches then its probably deficient in copper and zinc so its helpful to supplement with a mineral mix high in those two such as these here:
      Cheers, Cynthia.

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