A ‘Problem Horse’: Coping with EPSM

ESPM, or Equine Polysaccharide Storage Myopathy, is a metabolic disease that Jody Webb had never even heard of–until her horse was diagnosed with it.

From Jody:

Most people wouldn’t own my horse. If for some reason I couldn’t keep him myself, he would probably end up in the “glue factory.” Maybe I’m just crazy, or maybe I’m the sane one. Even though I believe there is a need for outlets for unwanted horses (highly controversial subject, I know), I own possibly the most unwanted horse of all.

Gideon is a puzzle. His breeding is half Eqyptian Arab and half Dutch Warmblood. I think they mixed kind of like oil and water. He looks mostly Warmblood but he acts mostly Arab. When I got him he was ugly as a rabid dog, minus the slavering mouth. He was also underweight, under-muscled and badly trained. He was also a “rescue” and the lady that currently had him didn’t know what to make of him either. He was too much of a handful and she wanted him gone!

When I took Gideon to the boarding stable I was at, I’m pretty sure people thought I was crazy. He was food aggressive, tried to bite about every three seconds, is a “windsucker” (cribber) and when I took him out to lunge him, he reared up and tried to strike me. But something in me wasn’t really afraid, just super cautious. I just laughed at him!

Over the following months we worked out SOME of the kinks. He still rears on occasion but stays well away from me, and I’ve learned its just his way of communicating anxiety or just being super playful. Depends on what day of the week it is. He is still grumpy where his food is concerned but he knows when to back away from it when I ask… grudgingly. And occasionally he will still think he can get away with trying to bite, and probably always will, but it keeps me on my toes.

I also discovered over those first few months that he has a metabolic disorder called EPSM, (Equine Polysaccharide Storage Myopathy). “What is EPSM?” you may ask. In this disorder the body is not able to store glycogen (the stuff that gives muscles energy) in the muscle, and they are now finding that in the EPSM horse that not only are they not able to store glycogen, but they mass produce it! So when he gets too many sugars and starches (much like a diabetic) he cannot store that energy and his body flushes it out in the form of muscle tissue. So as you can imagine, keeping weight on him is a real challenge and I spent an entire year perfecting his diet. The downside is it’s a giant pain in the backside. The upside is I’ve learned so much about nutrition, and hays, and herbs that I began selling specially formulated equine diets!

Managing Gideon’s weight wasn’t just a matter of changing his diet, but finding out what the problem was in the first place. Though he came with registration papers, he did not come with a giant arrow over his head stating “EPSM HORSE HERE! PROBLEM CHILD!” In fact, no one had a clue what his malfunction was, why he was so “touchy” and why his weight went up and down like Oprah Winfrey’s. In fact, with his symptoms, all anyone thought was he has general grouchiness, soreness from being exercised, and a very bad disposition! However, being a person with chronic back pain myself (and going through my grouchy stages as well) I knew there had to be a problem somewhere. Thank God for Google! And so I set out to research it myself.

My first information came from Beth Valentine’s website Rural Heritage after googling “Tying Up.” Though her research was mainly on drafts, much of the information fit Gideon’s behavior and led me to researching all I could about EPSM. Beth was also nice enough to chat with me via email about Gideon, and encouraged me to give the diet change time to do its stuff. After all, it couldn’t hurt as even healthy horses do very well on the EPSM diet.

Next was a visit to the Universaty of Minnesota website which expounded on what Dr. Valentine’s site stated. They have put more in-depth information on their site and continue to research this disorder, though their focus is on PSSM. PSSM is mainly quarter horse breeds while EPSM tends towards larger breeds like drafts and warmbloods. The symptoms are much the same in both cases, though they do vary slightly.

Symptoms of EPSM/PSSM include tying up (muscle stiffness, reluctance to move), sudden weight loss, sugar/starch sensitivity, shivers (loss of muscle control), skin sensitivity and general grumpyness. Symptoms may be mild or severe and anywhere in between. Gideon’s symptoms showed as tying up, lack of endurance, skin sensitivity, increase in cribbing, strong smelling urine (from shedding proteins) and hind end lameness.

Two years later and we’re still at it.  Gideon is stable physically, and well, mostly, mentally. We’ve been through torn ligaments, an infected kick from another horse, an argument with a T post, and the never ending attempts to get him to stop cribbing (or at least slow it down!)

I can’t imagine life without Gideon. Other horses may come and go but he will be a constant. Hopefully one day we’ll have our act all together enough that he will actually be the dressage horse I’ve always wanted him to be–he’s an awesome mover! But that may not be in his cards. Whatever happens, he will always be the horse I learn from.

Look for more episodes of “Gideon the Problem Horse”… coming soon!

http://www.Averagejo-Equine.com  – Stop by and leave a comment!


For more information on EPSM, visit:





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