EPM. Equine Protozoal Myeloencephalitis.
EPM is an invasive neurological disease that affects the central nervous system and spine. If not properly treated, it can be fatal and extremely dangerous to both horse and rider. EPM has no vaccine or prevention – it is spread only by opossums. Even once treated, EPM can come back (and has a bigger chance of coming back) at any time.
I should probably start with the fact that my veterinarian suspected EPM in West over two years ago. We did the blood test, which came back negative – and we moved on with our lives. Looking back, I’m convinced it was a false negative ( very common with EPM testing ) and he’s had it low grade this entire time, it just didn’t flare up significantly until last fall.
This past summer (2018) I started noticing small symptoms in West. Things like dull coat, weight loss, muscle loss, etc. All of these things had other logical explanations though. I was incredibly busy with work and travel all summer, so I turned him out and let him chill. It was his first summer ever living outside 24/7. I blamed the “sunbleached” coat and weight/muscle loss on this. I figured he was out in the sun, which was the reason for the drained coat. I also figured that he was sweating some weight out, and that he was losing muscle due to a dramatically reduced riding schedule. At this point, I wasn’t very worried about anything serious going on.
Towards the end of July, he started showing abnormal sweat patterns. Some days he looked striped like a zebra, some days he looked spotted like a cow. Some days he wouldn’t sweat at all, some days he was sweating to death under the fans. I figured that the 95 degree heat and 100% humidity was just getting to him. I had seen others post about their horses having weird sweat marks too, so I figured it was nothing.
It wasn’t until symptoms got more severe that the thought crossed my mind that something could actually be wrong. His muscles continued to waste despite increased feed, supplements, and conditioning. I could see his entire spinal column. He became extremely lethargic. He started stopping at fences, which if you know West – never happens. He also started refusing to work. It took all the strength I had to get him to canter. Again, if you know West – this is extremely abnormal. He loves to go. It usually takes everything I have to STOP him, not make him go. He began rearing when asked to go into the ring. He became sloppy in his work, extremely hollow, and overall just very unwilling. Not like him. He also began tripping, which isn’t necessarily out of the ordinary for West – he usually trips a bit when he gets towards the end of his four week shoeing cycle, but he was tripping significantly more.
Shortly after the under saddle symptoms began, West was due for the farrier. I’ll never forget that night. My appointment was at 5 pm, I didn’t end up leaving the barn until 9:30 that night. West has always had great feet, physically. We’ve never really had much trouble with cracks or breakage, maybe just a little here and there. His feet during this time were literally falling apart. So much so that my farrier had no foot to nail in to. Our only option was to do glue ons, and use acrylic to create an artificial wall where his foot was shelling away. It took four hours for my farrier to get two shoes on West. Who mind you, normally sleeps in the cross ties when he is shod. He’s never been a problem for any farrier. He was rearing, striking, biting, everything. I was fully expecting my farrier to quit that night.
It was so bad that he had to put West in a stall, pin him against a wall, and put hay in his face to even try to hold him still long enough for the glue to set. It got so bad that I couldn’t even handle him. Travis had me step away and let his assistant Keith hold and handle him. After four hours of battling, Travis and I agreed that that was enough for the night. We didn’t want to push him any further because something was obviously wrong. He would survive without his hind shoes until we figured something out. Travis felt that West’s behavior was pain related. West had never been a problem for him before, and Travis actually enjoyed working on West because of how good he always behaved.
The next day, I had my barn owner look at him. He immediately suspected EPM, specifically because of the weight and muscle loss. He told me that he was constantly upping West’s grain. West, who is typically a very easy keeper, was eating enough for six horses per day. Justin is a lifelong horse owner, professional polo player, and equine chiropractor. When you have 40+ head of horses at any given time, you learn to do a lot of your own medical work and examination. He’s had dozens of horses with EPM over his life time, so he’s picked up on the physical tests that some veterinarians do during diagnosis. These tests are not sure fire ways to determine a horse’s condition, but usually if a horse is reactive – it’s an indicator that something like EPM might be going on. West was highly reactive to each test that he performed.
Next line of action was to get my actual vet out. She pulled his blood and ran all the tests. She redid the physical tests that Justin had done the day prior, with the same results. To no one’s surprise, his EPM test came back positive.
Next step was choosing a treatment. We caught the disease early, and my vet deemed West “non neurologic,” meaning as far as we could tell by diagnostics, his symptoms were merely physical. She recommended a compounded medication called Toltrazuril, and if that didn’t work, we would move forward with the Marquis.
West received an entire tube of Tolt. on day one, four, seven, ten, seventeen, twenty four, thirty one, and thirty eight. Within a week we noticed incredible improvement. His coat started to come back, and he was putting weight back on. He completed treatment, and myself, my vet, and my barn owner felt that it was enough. We stopped treating, and if West relapsed, we would go ahead with the Marquis.
So far – so good! West bounced back quickly and stronger than before. Along with medication, I started West on HG Super Weight Gain and Vitamin E, which is recommended for horses with EPM. The combination of the three completely transformed him back into the handsome, flashy horse that he is.
After treatment was over, West was cleared to begin light workouts – lunging and tack walks. After several weeks of that, he was able to go back to normal work under saddle, with heavy focus on building up his topline.
As a result of the disease, West did have to be retired from jumping. Well, he didn’t necessarily “have” to be retired, but both me and my vets thought it would be best. Often times, horses with EPM show lasting symptoms even after treatment. West is still tripping – not like he was when he was sick, but he might trip once or twice per week now. I don’t want that trip to be coming down from a 3’6 oxer. It just isn’t worth it, for either of us. I felt that even before his diagnosis, West was trying to tell us that he was finished. A horse only has so many jumps in them.
Looking back, all of the little symptoms make complete sense. His coat was disgusting because he was sick and unhealthy. His topline diminished because the disease was targeting his spinal column. He was losing weight because he was sick and had a compromised immune system. His feet were falling apart because his body was weak. He was a nightmare for the farrier because he was miserable. He performed poorly under saddle because he was in pain. He showed bizarre sweat marks because that is a little known symptom of the disease.
West still plays over small jumps at home, but as far as his jumping career, that is over. He is now a full time dressage king – and loving it. It has been almost eight months since he was diagnosed and treated, and he is doing fabulous.
I’m so so thankful that we caught his symptoms early. I fear what could have been had we not. His treatment went smoothly, and he has remained healthy since. EPM is such a hard thing as a horse owner, but thanks to developing medicine and technology – it is no longer the end of the world!
If your horse has had EPM, or you are currently battling it – lets chat! My Instagram DM’s and Facebook messages are always open! <3
If you want to learn even more about EPM, here is a great link!