Summer Sores and Horses

Summer Sores and Horses

Whinny’s Wisdoms

Springhill Equine Veterinary Clinic

Hey everybody, Whinny here! Although it’s not quite technically summer, the warm weather has arrived in full force in Florida. With the onset of heat, we’ve had an eruption of flies! And once flies begin pestering our horses, we soon run into a common Florida problem: summer sores.

Summer sores are caused by a stomach worm called habronema. Normally, the larvae of the habronema hatch out of horse manure and are picked up by flies. Then, the flies are supposed to deposit the habronema larvae onto the mouth of the horse where they are ingested. Once they are in the horse’s stomach, the larvae are produced and passed back into the horse manure to complete the cycle. That’s a complicated life cycle! Makes me glad I’m a mouse.

This stomach worm usually does not cause any disease or illness when the cycle occurs in the usual way. Summer sores, also known as habronemiasis, develop when the habronema larvae are deposited in the wrong place. The locations include wounds and mucocutaneous junctions, so around the mouth, eyes and genitals.

Classically, summer sores appear as circular wounds that are not healing. They may also be raised or have exuberant granulation tissue, which is colloquially known as proud flesh. In some cases small, hard yellow pieces called sulfur granules are found in the wound. These granules are formed as a calcifying reaction around the habronema larvae because they are not where they are supposed to be. Aggravatingly, these wounds can occur even with the smallest cut or break in the horse’s skin, so prevention is key, otherwise we can end up dealing with a sore all summer long!

Springhill Equine Veterinary Clinic

The most common mucocutaneous junction that can be affected is the medial canthus, or the inside portion of the eye. Horses are very likely to rub their eyes if they are harboring summer sores there, predisposing them to corneal ulcers. As if horse eyes don’t have enough problems!

Prevention starts with keeping wounds clean and wrapping or covering any wound until it is healed. Pasture management and manure cleanup are also essential in order to minimize the population of flies that are on your farm. During the spring and summer months, horses should really be wearing fly masks to limit their exposure to flies and their likelihood of contracting ocular summer sores. In instances where a wound cannot be wrapped, some creativity may need to be involved or they may need to be stalled with a fan periodically to keep flies off as much as possible.

Although they can be a pain and take time to heal, summer sores are treatable and they do heal eventually, especially once we enter the winter months. Treatment may include surgically debriding wounds, topical treatments or injections with steroids mixed with antibiotics, and oral deworming. Keep in mind that not all dewormers are created equal. Summer sores should be treated with Quest (moxidectin) based on your horse’s weight.

If you suspect your horse has a summer sore give my docs a call! Proper diagnosis is always key in expediting treatment. Summer sores can occasionally be misdiagnosed as squamous cell carcinoma, sarcoids, or pythium, but the veterinarians at Springhill can set you on the right path.

Until next week,

~Whinny

P.S. Have you seen the new YouTube series called Horse Girl Goes to the Vet on our YouTube Channel? I promise you don’t want to miss it! I’ve heard people say the Horse Girl looks a lot like Dr. Lacher’s husband, but I don’t see the resemblance, myself. Anyway, there are way over 100 videos about all kinds of horse health things, much like my blog, and you don’t want to miss out on that great free resource. Your horse will thank you, and so do I!

Whinny’s Wisdoms is the official blog of Whinny the Clinic Mouse at Springhill Equine Veterinary Clinic in Newberry, Florida. If you liked this blog, please subscribe below, and share it with your friends on social media! For more information, please call us at (352) 472-1620, visit our website at SpringhillEquine.com, or follow us on Facebook!

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More Adventures of the Horse Doctor's Husband
Summer Sores

Summer Sores

Tuesdays with Tony

Warmer weather is moving in, and along with it are some familiar visitors: flies! And in Florida, flies mean summer sores. Read along to learn everything you never wanted to have to know about summer sores, including how to prevent, identify, and treat these unwelcome, unpleasant, and unsightly buggers.

Springhill Equine Veterinary Clinic

What are summer sores?

     The short version, because I’m a very busy cat and I haven’t got all day. Summer sores, technically termed Habronemiasis, happen when insect larvae end up in the wrong place: namely either in a wound or in your horse’s mucous membranes such as eyes, lips, or genitalia.
      Habronema is actually the horse stomach worm, and rarely causes any problems when it stays in the digestive tract where it belongs. However, when the larval stage is deposited in a wound or elsewhere on the skin, instead of being ingested by the horse, it causes a major inflammatory reaction.
       I guess it’s kind of a bummer if you’re a habronema larva…it would be like getting dropped off at the wrong house by your Uber driver. (The Uber driver in this scenario would be a house fly, face fly, or stable fly; and your pick-up location would be a steaming pile of manure.)

Habronema in Wounds

      Summer sores that develop in wounds are actually the easiest to prevent. Here’s the secret: cover them up!! For wounds on the legs, this means bandaging. For the face, it means a fly mask. For elsewhere on the body…time to get creative! Summer sores are definitely one of those places where an ounce of prevention is worth a pound of cure.
     Even the tiniest break in the skin can offer an opportunity for habronema larvae to be deposited and set up shop. Be wary of summer sores anytime you are dealing with Scratches on the back of the pasterns, nicks from walking or riding through thick brush, and of course any time you have a wound big enough to require stitches.
Springhill Equine Veterinary Clinic    In fact, preventing summer sores is one of the best reasons to have those borderline lacerations stitched up. The less space flies have to land, the less opportunity they have to drop a little habronema larva in there too. And believe me, flies LOVE wounds! Yummy, weeping serum, blood droplets, maybe some pus…it’s a fly dreamland! For those wounds on the lower limbs, we love Sox for Horses Silver Whinnys. They provide a good combination of skin coverage and breathability, while the silver-impregnated threads help the wound to heal.

Habronema in Eyes

    If I were a fly, the choice between landing in a weepy eye or a bleeding wound would be a real toss-up. Decisions, decisions. I guess I’d have to say the eyes have it, because horses always (well, usually) have 2 of those, whereas the wounds are more of a hit-or-miss thing.
    I guess what I’m really trying to say here is, keep a fly mask on your horse. Especially in the summer. And especially during the day. If your horse has allergies, uveitis, or otherwise tends to have runny eyes, then he probably should have a fly mask on 24/7/365. No, it doesn’t hurt to do that, as long as you are peeking under the fly mask at least once a day to make sure there are no  hidden injuries. Yes, they can see through a fly mask, even at night.
    Ocular habronemiasis, or habronema in the eye, is probably the most common location where my docs find these parasites. The larvae are deposited and then migrate into the conjunctiva, the third eyelid, or the nasolacrimal duct which runs from the inside corner of the eye to the nose.
    Once these larvae realize they are in the wrong place (i.e. not the stomach), they die. But THEN their little bodies calcify into this hard, yellow granular material, the consistency of which is not unlike concrete. Imagine several of these rock-hard dead larvae carcasses imbedded in your horse’s eyelid and I bet you can guess what comes next: a corneal ulcer.
    Now, you know from reading my blog and coming to my seminars that corneal ulcers are always an emergency, and often a bad deal because they can become infected so easily. With corneal ulcers caused by habronema, you have the added disadvantage of a jagged calcified granule rubbing up against the cornea and not allowing it to heal. So, not surprisingly, my vets will do their best to remove these dead larvae before they can cause any more damage. This involves squeezing them out like a pimple, pulling them out with tweezers, or flushing them out through the nose with saline. Spoiler alert: this is not a fun procedure for your horse. So, again, FLY MASK!

Habronema anywhere else

Springhill Equine Veterinary Clinic    The tough summer sores to treat are the ones that occur somewhere that is impossible to wrap and too deep to dig out. Common locations for these include the corners of the mouth and the sheath on males. These summer sores usually need to be treated aggressively and repeatedly by a veterinarian. My docs have a special cocktail of a dewormer, a steroid, and DMSO that they will inject directly into the summer sore. This combination is aimed at killing the larvae while also treating the severe secondary inflammation associated with habronemiasis.
    In addition to local injection, my docs will also instruct you to deworm your horse with Quest. Why Quest, you ask? Because Quest contains Moxidectin. Similar to Ivermectin, the active ingredient in most dewormer, Moxidectin is the strongest drug in its class. This is probably the ONLY time you will hear me recommend Quest, as we try to reserve it for treating summer sores and not use it on deworming for internal parasites.
    The silver lining, if there is one, is that summer sores are not life-threatening, and they will heal eventually. As the name implies, summer sores are almost exclusively seen during periods of warm weather. As such, winter in itself cures most summer sores.
    So, now you know all the secrets. If you would like to pick an expert’s brain on Ocular  habronemiasis as well as all other eye things, don’t miss my next seminar, All About Eyes, on May 2nd at 6:30pm, featuring Dr. Dennis Brooks!
   Until next Tuesday,
           -Tony

Tuesdays with Tony is the official blog of Tony the Clinic Cat at Springhill Equine Veterinary Clinic in Newberry, Florida. If you liked this blog, please subscribe below, and share it with your friends on social media! For more information, please call us at (352) 472-1620, visit our website at SpringhillEquine.com, or follow us on Facebook!

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Summer Sores

Summer Sores

Tuesdays with Tony

It’s a wound, it’s a tumor, no wait…it’s a summer sore! The docs have been reporting a lot of these ugly things recently. Maybe it’s the weather we’ve been having. Maybe it’s just the fact that we are lucky enough to live in glorious Florida!! Whatever the reason, summer sores have been popping up left and right, so here I am to tell you what to do about them.

 

Summer sores are gross

 

I hope you’re not eating, because this is pretty gnarly. Summer sores happen when larvae from the stomach worm Habronema are deposited in a wound or mucous membrane. Yuck! The larvae cause a severe inflammatory reaction in the skin, which creates the red, thickened, oozing granulation tissue we so fondly recognize as a summer sore. They commonly occur on the legs, in the inner corners of the eyes, on the sheath, or in the corners of the mouth. I’ve never had one myself, but they don’t look like much fun.

 

“Summer sores” are not always summer sores

 

If you suspect your horse has a summer sore, the first thing you should do is definitely call Springhill Equine. There are certain more severe skin conditions (sarcoids, pythium, squamous cell carcinoma) that can masquerade as summer sores, so a proper diagnosis by one of our docs is important. The treatment for these skin conditions is not the same across the board, and treating them like you would a summer sore could actually make them worse.

 

How to kick a summer sore’s butt

 

First, deworm your horse with oral Ivermectin, if you haven’t already. This will not only kill any stomach worms in his belly, but also any larvae living in the wound on his skin. Then, put some antibiotic ointment with steroid on it. The steroid will help with that excessive inflammatory response to the larvae, and the antibiotic will prevent the wound from becoming infected. Finally, cover the area with something loose that will keep flies off. On the face, a long-nose fly mask works best. On the legs, Sox for Horses are great. In aggressive cases, one of the docs may have to surgically remove and/or inject the summer sore to get it to go away. Also, winter helps (providing we actually get a winter this year).

I doubt you will have any questions, because I am pretty much perfect when it comes to explaining things. But if you do, you can always give me a call or a visit here at the clinic, and I will direct you to one of our three amazing docs in exchange for some scratches right there behind my ear.

Until next time,
      -Tony

Tuesdays with Tony is the official blog of Tony the Clinic Cat at Springhill Equine Veterinary Clinic in Newberry, Florida. If you liked this blog, please subscribe below, and share it with your friends on social media! For more information, please call us at (352) 472-1620, visit our website at SpringhillEquine.com, or follow us on Facebook!