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Miles Licking Wood July 2014

Battle Rain Rot

Even though Miles is only my second horse, I’ve been an equestrian for more than 10 years. I’ve seen and dealt with my fair share of lameness, wounds and general equine issues. However, it never ceases to amaze me that no matter how much you think you know, there’s always something new you can learn about horses. Currently, Miles is teaching me all about rain rot… and I have to admit, it really sucks. I’ve definitely gone through a variety of emotions [from worry, to terror, to anxiety and even depression] but I’m starting feeling a bit better since this nasty fungus is finally starting to clear up. Anyways, I thought I’d share with you all a bit about the lovely stuff I’ve been dealing with… cause I know rain rot is extremely intriguing [heh].

All About Rain Rot

Rain Rot has many different names in the equestrian world including: rain scald, mud fever, scratches and sweet itch. Rain Rot is a fungus caused by dermatophilus congolensis, a bacterial organism whose natural habitat is unknown. Attempts to isolate it from soil have been unsuccessful, although it widely believed to be a saprophyte in the soil. Rain Rot is spread by direct contact between infected animals, through contaminated environments or possibly via biting insects. Factors such as prolonged wetting by rain, high humidity and high temperature can influence the development, prevalence, seasonal incidence, and transmission of Rain Rot. In the early stages of infection, you will feel small lumps on the horse’s skin/hair by running your hand over his coat. As Rain Rot progresses, matted tufts of hair may appear as well as large (sometimes crusty) scabs. There are usually dozens of tiny scabs that have embedded in the horse’s coat and can be scraped off. Underneath the scabs, sometimes the skin is pink with puss when the scabs are first removed, then it becomes gray and dry as it heals.

In layman’s terms, we really have no idea how horses get rain rot and it’s a really disgusting problem to have.

Rain Rot Infographic

How to Treat Rain Rot

Step 1 Do not Google or go on the Chronicle Forums for advice. You will be scared silly, see terribly horrific pictures and spend a small fortune at Whole Foods and CVS. Plus, your horse won’t get any better. Trust me, I tried it.

Step 2 Pick off all the scabs. Wipe your hand across your horse’s entire body and anytime you feel a small lump, pick it off. If the scabs are tough and a little painful (I found this to be the case most often on Miles’ legs), wipe some baby oil on them and let it sit for a few minutes. The baby oil will soften the scabs and make it less painful to remove them.

Step 3 Don’t panic when you remove all the yucky gunk from your horse’s back and realize he’s now bald in large patches. Take a deep breath and evaluate the now exposed skin. Is it grey or pink? Pink = infected, grey = good.

Step 4 Skip all the home remedies and go straight to what works: Chlorhexidine. I got a shampoo [Equishield Ck Shampoo] and a spray [PhytoVet CK Antiseptic Spray] from my vet. Both contain 2% chlorhexidine gluconate and 1% ketoconazole. I bathe the infected areas three times a week, and spray once a day; and I promise it’s like magic. I saw immediate improvement after just the first use!

Step 5 Contain the infection by not sharing brushes or saddle pads with other horses. Wash your hands thoroughly after grooming before touching other horses, and I would recommend regular sterilization of grooming tools with bleach water. If the infection is anywhere near your saddle or girth area, it wouldn’t be a pad idea to also wash your saddle pads more regularly, and use a washable girth cover as well.

Miles Rain Rot July 2014
Left and right side of Miles, where his rain rot is the worst.

Miles’s Battle

I first noticed some Rain Rot on Miles’s back at the New Vocations Charity Show over July 4th weekend. It was two small spots, and I picked off the scabs, treating with MTG to help the hair grow back. Not too long after we got home from the show, it seemed that every day I came out, there was a newly infected area: the shins of his front legs, followed by the back of back legs, and then on either side of his back [right above the stifle]. After totally freaking out that my horse was becoming a hairless Mexican Chihuahua [and trying every trick I could find on the internet to no avail] I finally called my vet who dropped off the medicated shampoo and spray I mentioned in Step 4.

Since then, the rain rot is slowly disappearing. His legs are almost completely healed, his sides only have minimal infection and the fungus isn’t spreading nearly as quickly over his back. Plus, it hasn’t sprouted up anywhere new. Hallelujah!


Fly On Over is an equestrian lifestyle blog devoted to connecting horse lovers around the world. By providing equestrians with practical tips and tricks related to horse ownership, discussing training techniques for horse and rider, as well as covering industry news.

13 thoughts to “Battle Rain Rot”

  1. Great article! I’ve always had excellent luck treating rain rot by scrubbing with betadine. I wonder what the differences are between that and the medicated stuff the vet gave you. I’ll agree, when using anything else, it’s almost impossible to get rid of.

      1. Both chlorahexidine and betadine are excellent antiseptics, but the reason that chlorahexidine was found to be more protective in that study is that chlorahexidine has a longer residual activity (meaning it will continue to protect against infection) than betadine. However straight chlorohexidine (aka not when mixed with other things like as is the case in your spray) can be more irritating to some animal’s skin. At the hospital I worked at, when we scrubbed a horse for surgery we would scrub the entire clipped area with betadine, and then put one small strip of chlorahexidine right over where the incision was going to go.

  2. Last summer when O had access to go swimming she has it AWFUL on her legs. This year I’ve been obsessive and so far have kept it mostly at bay, but it is zero fun 🙁 Glad you found something that worked so well!

    1. I think Miles’ skin genetics just blow, because I’ve been pretty diligent about keeping him clean and dry and the stuff just seemed to crop up overnight! I think part of it was he was going out at night, and it was just so damp and humid this year 🙁

  3. Rain rot sucks, I’m glad that you’ve gotten it under control. I’ve always found that the MOST effective thing is getting the scabs off and keeping the skin as dry as possible. Some people start overdoing it with all of the bathing/shampoos/etc. I really like the EquiShield Products too. =-)

    Since you have been interested in learning more about rain rot, I wanted to make a few small corrections to your lovely blog post. First, rain rot is not a fungus. Dermatophilus congolensis is a bacteria; bacterial organisms differ from fungal organisms in their cell structure and metabolism. I know that seems like a trivial difference, but we use different drugs to treat fungal infections than bacterial ones, so knowing what exactly you are dealing with helps picking an appropriate treatment.

    When horse people talk about sweet itch, they usually are talking about a totally different disease. Sweet itch usually refers to an insect hypersensitivity. Look up culicoides hypersensitivity if you want to learn more about sweet itch (and be thankful that Miles does not have it). Scratches is also a different disease- that refers to the scabs/sores horse get on their pasterns and it has a variety of causes.

    Just thought you might like to learn a bit more =-). Good luck with Miles!

    1. Thank you for the corrections! I will have to update my blog post so I don’t confuse anyone. I’m always learning and I appreciate the info!!

  4. That first sentence in that graphic is really awkward, LOL….with the fungus caused by bacterial organisms….

    Well…fungus are fungus, bacteria are bacteria except there are bacteria with fungal type properties, but they really don’t cause a fungus, they just are what they are.

    But I am glad someone else has seen the light about using a proper antiseptic instead of saukerkraut or 1001 other goofy things I’ve seen lately….

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