Strange Skin Ailment--what's your guess?

[PNG_Pony]

I have a mare with a strange skin ailment that we can't seem to beat, so having exhausted most of my options, I once again turn to my trusty armchair vets

(For those of you who don't know yet...here's my disclaimer: I live in Papua New Guinea, a third world tropical island nation north of Australia, that really was never intended to support horses. There are no vets here, no farriers, no physios, no chiros... no nothing. Not even stalls or hay. Equine nutrition is sketchy, but we've done the best we can by creating a personal mix of various minerals specific to our herd of 9 stock ponies and we've seen great improvement.)

This is a 26 year old QH mare who has two odd patches on her body: between her front legs (girth area) and on the right side of her crest in the middle of her neck. Both of them are behaving slightly differently, despite having been treated extensively, we’re getting no-where. Neither of them are rain rot/rain scald (which we deal with a lot here), nor do they appear to be Queensland Itch.

The one on the stomach is itchier of the two. It has lost hair in about a 4” diameter patch, but there are a few smaller spots as far away as 12” from the main spot. Some hair has grown back, actually, but in the middle of the hairless spot, it has developed blotchy black speckles on the skin (not like normal dark skin, but oddly colored spots). The skin is flaky.

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The one on the crest is a 4” diameter spot with no hair (and again, spotted skin). It has strange lumps under the skin, which seem to shift and change position gradually (over a period of weeks). This one isn’t really as itchy as it used to be.

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We’ve treated these for several months now, with no changes, and instead the one on the crest has grown. At first, they seemed like rainrot, so we attacked it in kind (we're rainrot experts here in the tropics...); we either use an effective herbal treatment from Zephyr’s garden or a potassium permagenate mixture. Both tend to clear it up right away. With this, it wasn’t working. In desperation, we’ve moved on to other things--we’ve tried antiseptic washing and normal washing, we’ve tried hydrocortisone creams, we’ve tried anti-itch creams (including stuff with zinc, like desitin), we’ve tried some other fungal treatment begged off our local clinic (whitfield’s ointment) and it doesn’t seem to be making any difference, despite twice-daily treatment.

Thoughts?

[Fatcat]

Have you de wormed her with ivermectin? Making sure she got a generous dose?

[PNG_Pony]

Yes, we just dewormed with ivermectin again, and back when this first arose I treated her for neck threadworms (one of our other mares here has those and ivermectin is the only thing that controls her itchiness.) It made no difference.

[myleetlepony]

Just curious, did you try putting the ivermectin on the spots? I don't know how easily you can obtain it down there, or if it's a precious resource, but if you can spare it, I'd give it a try. The strange lumps moving around makes me think burrowed parasite...

[svvdressage]

Just curious, did you try putting the ivermectin on the spots? I don't know how easily you can obtain it down there, or if it's a precious resource, but if you can spare it, I'd give it a try. The strange lumps moving around makes me think burrowed parasite...

This is what I was going to say.

[PNG_Pony]

I hadn't thought of putting ivermectin on it topically; I've got some extra paste lying around, so we'll try that. Thanks for the idea!

[myleetlepony]

If you have some liquid DMSO on hand, you could mix a little bit with the ivermectin to help carry it through to whatever might be living in there; that's what I ended up doing to combat a few summer sores once.

[kande50]

My mule had a half dollar sized lumpy, hairless patch on his inner thigh a couple years ago. I dewormed with ivermectin with no change, but then a few months later it went away. No idea what it was, as I've never seen anything like it before or since. The lumps under the skin seemed like they were in a symmetrical pattern, or were at least evenly distributed, with about a dozen lumps in that half dollar sized patch.

[angela9823]

Only other thing I can think of besides what other said, try washing with a mix of tea tree oil and aloe. Sometimes you can find shampoos with this already (even dog shampoos) but other times you can mix it yourself. Antiseptics can leave the skin scaly like what you are seeing in your pictures but tea tree oil with aloe seems to soothe the skin. If you are damp there, maybe the horses are getting a bit of a yeast infection. Dogs can get it and it looks just like what you have there. You can follow it up with a bit of listerine and water sprayed on and left on the skin for good measure.

Don't mix the tea tree oil strong. Just a few drops with an aloe will work.

[PNG_Pony]

Hmm, I think I've got some DMSO somewhere.

kande--yes, I've not seen anything like this either. Some of our horses get hives or insect bites, but this isn't that...

Tea tree oil with aloe is a good idea; we've used it on some other horses, but I didn't think to put it on her. And I have the listerine/water mixture too.

I decided to give her one more double-dose of ivermectin orally as well, just in case it is a really stubborn case of neck threadworms and needs a couple of treatments (but why the patch on the belly too? odd.)

[Josette]

This reminds me of "ringworm" which I saw many years ago. It is really a fungal infection and there is the scaling skin and hair loss.

http://www.pets4homes.co.uk/pet-advice/ ... orses.html

http://horses.about.com/od/commonproble ... horses.htm

[Moutaineer]

Could well be ringworm or some other fungal infection. A little Clorox will clear it up quicker than the fancy creams if so. (I caught ringworm from a rescue horse about 2 weeks before my wedding...)

[PNG_Pony]

Yes, my first guess (after the rainrot was ruled out) was ringworm, and we treated it accordingly, but it never changed (though didn't try Clorox). It seemed fungal, so we've since tried a couple other creams, but it doesn't seem to be responding.

[Josette]

What about trying a spray like for athlete's foot fungus?

[PNG_Pony]

Hm, now that's a thought!

Our semi-optimistic update is that after daily topical application of ivermectin the lumps in the neck appear to be diminishing slightly and hair seems to be growing back on the belly, so maybe that's the trick! We'll keep going and see what happens.

[myleetlepony]

Let's hope it keeps going in that direction! Keep us updated!