Polysaccharide Storage Myopathy (EPSM)

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Tonks

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I suspect my newly bought ISH has the condition and is due to have tests soon.

I am keen to start the diet asap and although I've done some research and informed myself about low carb, high fat diet (1 pound fat - corn oil - per 1000lbs horse/alfalfa pellets/speedi beet/Vit E/Selenium) I am at a bit of loss regarding forage/hay.

I have read that you should feed Legume hay but I assume this may be prohibitively expensive and difficult to source.

Can I soak normal seed/meadow hay?

Any experiences of this condition would be most welcome. Thank you.
 
You'll find a few threads on it if you do a search, but a few thoughts from me:

Worth looking at:

- Beth Valentine's stuff on the Rural Heritage website (her ask the vet posts are well worth reading).

- Stephanie Valberg's stuff on the Minnesota university website

- Also worth joining (free) Dr Kellon's EPSM yahoo group - plenty of interesting stuff on there

I also found this paper interesting - there are so many more muscle diseases than just EPSM, so worth seeing whether anything else is more likely to be the case:

A review of equine muscle disorders by M. Aleman *
http://maquette.respe.net/system/files/documents_equine_muscle_disorders.pdf


Also worth being aware that there are different thoughts on the high fat diet. Some would have you believe it's the answer to just about everything, but you need to know that fat is about 5 times as calory-dense as hay, so if you gradually build up to feeding 1lb of fat, then you will need to reduce the hay by around 5lb to avoid weight increase. This may or may not be feasible, without reducing the horse's fibre intake too much. Also be aware that feeding fat may increase insulin-resistance and therefore render the horse more liable to laminitis. For hardworking horses, replacing any starchy feed with oil may well work, but I'd be very cautious with a leisure horse in light work. Anyway, something to be aware of and make your own mind up about.

What makes you think it's EPSM? What's the pattern of signs?

Depending on the horse's breeding, it may be worth just having some hair tested (very cheap, about £30 by Animal Genetics in Cornwall) for type 1 EPSM (which is the only type for which the gene mutation is known). Minnesota have a good flow chart on their website suggesting the path for diagnosis for different breeds/types of horses.

Certainly hair testing is far cheaper and less invasive than the hamstring biopsy, and if you can confirm diagnosis via that, then brilliant.

I don't think any of my gang have EPSM. One showed no abnormalities on biopsy. All tested negative for type 1 on a hair sample. I've pursued it being a selenium deficiency, but we're still not certain, although the diet definitely only had about a third the recommended level of selenium until recently. A full ration of a good balancer like Top Spec addressed that deficiency.

However, if you suspect selenium deficiency make sure to have hay/grass analysed, and check selenium content of all feeds before supplementing. Selenium very soon becomes toxic if fed a little above recommended levels, and can cause very severe problems at high levels.

Good luck.

Sarah
 
Thank you for you reply.

Very interesting and you sound very informed.

I did managed to read the articles/sites you mentioned before posting, but haven't managed to come to much of a conclusion regarding forage/hay - what to feed and how much.

Do I need to soak normal meadow/seed hay or do I specifically need to feed alfalfa hay?

He is ID x TB. 5 years old.

I have had him now 4 months and his canter has not progressed as it should have. He was about the 25th horse I looked at with pretty good confirmation, moved beautifully [in walk and trot] and had a good jump.

His canter was very green when I tried him out and he bucked in canter.

This did raise alarms bells for me, so I asked vetting vet to check for possible causes (along with flexion tests.) I also had a pre-purchase blood profile taken to check for general blood parameters to include muscle enzymes, which indeed, came back high (AST).

The vet explained this as muscle soreness due to a severe cold.

I decided to buy him - as he totally stunning with the most amazing trot and lift in the shoulder.

I had another blood analysis done about 2 months ago which again showed reasonably high levels of AST which the vet explained as muscle soreness due to the starting more 'proper' work which is pretty common in youngsters starting out. So, wasn't too concerned at this stage.

In the meantime, I gave his canter the benefit of the doubt being a youngster.

However, after 4 months of work, his canter is not what is should be:

1. He is unable to show any basquel (spelling?) or upward movement through his back in the canter.
2. As a result, he is unable to engage his hindquarters and lift the shoulders as you would begin to expect for age and level of work I would be expecting him to work to.
3. Gait abnormality in canter - frequently changes behind.
4. frequently falls back into trot from canter.
5. Slows an abnormal amount of flexion behind when incorrectly changing behind (high stepping.)
6. Reluctance in all gaits to move forward and be off the leg.
7. Forges - as his hind legs have the ability to swing back and forward quite far (trailed out behind him) in the stance and swing phase but lacks the ability to flex upwards - which is direct contrast to the high steps we get when changing behind or falling back into trot. This is not characteristic of stringhalt/shivers/upward fixation of the patella.)
8. Soreness over lumbar and sacral area.

I use two vets, one of which is pretty high profile. Blood profile from yesterday showed no raised CK or AST levels. He suggested Toddie be referred to a physio. However, my research tells me that blood analysis should be taken 4-6 hours after 20 mins of walk/trot work to show any enzyme peaks. Tods hadn't been worked for over 48 hours.

Moreover, I have read that draughts especially, may not show particular high levels or peaks in their CK or AST levels or differ from enzyme reference levels. I haven't raised this with my vet as yet because I want to be more informed at this stage. Indeed, given that treatment for EPSM is largely diet related I may not need to have a confirmed diagnosis from my vet, other than for insurance purposes.

I also had another vet out with a thermography camera who has stated that he's physically weak with some bone fusion changes occurring at the wither and he also showed inflammation in the right hind gaskin, which may make some sense. He stated that poor confirmation is causing his problems - not sure I agree with this one.

My approach will be to change diet, get hair analysed for genetic testing as you mention and also get a physio in, so all basis are covered.

I understand that a comprehensive exercise programme is also recommended - any thoughts on this?

Did you use Animal Genetics based in Cornwall? Are they reputable or do you have other suggestions?

Thanks very much.

Any thoughts gladly welcome.
 
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So sorry.

I keep trying to reply to this.

Typing a long reply, pressing send, and then it tells me I'm not logged in and I lose the whole message. Arrrrggggghhh. Done that twice now!

Will type it up in Word tomorrow and try and repost.

Long and short is I'm not convinced that it is EPSM, but I could be wrong as I'm no expert. Could you take him to someone like Sue Dyson for a bone scan in case it's spinal/pelvic stuff?

Like I say, I'll add more detail tomorrow.

Sarah
 
I've had that....frustrating....!

I have taken hair sample this evening and will post tomorrow.

I am open to all suggestions and will try a multi discipline approach to cover all bases.

The test should give me a definitive answer as to EPSM and will take it from there.

Hopefully physio will contact me soon and she will be able to give me her thoughts and indeed, let me know if she thinks it's more soft tissue or skeletal. I am hoping that it's not skeletal - however, in my experience sacro-iliac problems are notoriously difficult to a) diagnose and b) treat, whether soft tissue or skeletal but you never know.

I am trying to be possible and tell myself that with each new horse I've ever had, I can think of a single one that didn't have 'teething problems' that needed to be overcome.

I think it's about elimination at the moment. He's such a lovely boy that it will be worth the while taking time to get him right.

Thanks for your reply and concern and all thoughts welcome.
 
OK, trying again to post a longer note….

I don’t claim to be an expert or well informed, but I have had to do a fair bit of reading to try and narrow down what’s happening with my gang, so if anything I have come across is helpful then great.

I think Beth Valentine recommends alfalfa hay, but that is to try to keep protein levels up if the horse is losing muscle mass. I guess by using a balancer you can keep protein levels up without needing to opt for alfalfa. Mainly I’d just opt for keeping grains/starch to an absolute minimum as this seems to be a key thing for horses. I don’t think it’s as important to soak as it is for laminitics. With laminitics, you are trying to reduce sugar levels, whereas for EPSM horses the sugar isn’t a direct problem (though you might choose to soak to keep calories down a little, especially if you are using an oil diet and having to trim calories in other areas).

The key things I’ve picked up on as being signs of EPSM are an increasing reluctance to work after 15 or 20 minutes or so (when the horse has to switch to using glycogen for energy, and this is when an EPSM horse runs out of fuel) and a stilted hindlimb action. Yes there are other signs too, but on those first two things it doesn’t sound as though your horse fits the bill – you say he gets quite high stepping when switching leads, and that he forges as his hind legs engage so much.

AST can indicate either muscle or liver damage, and the levels of other enzymes may help indicate which.

“The vet explained this as muscle soreness due to a severe cold.” Seriously?????? Words fail me.

I think I’m just not convinced there’s enough to suggest EPSM, but hey what do I know, and like with all sorts of problems, an animal doesn’t necessarily show all signs. But what you say about him failing to sustain the canter, switching leads and bucking in canter could fit with other stuff like spinal/pelvic problems. What is he like doing a tight turn on the forehand – sometimes pelvic problems show up as a difficulty/unevenness in doing ToF as the horse struggles to put its inside hind right under the belly.

It sounds as though you are sure there is a problem, and that it’s not just a normal young horse trying to find his balance.

If your horse is covered under insurance for investigation, then I’d ask for a referral to someone like Sue Dyson at AHT for a bone scan (and/or anything else she suggests) to try to get to the root of the problem.

I wonder what the thermography vet meant by poor conformation – maybe that might point to a possible cause (eg some problems are more likely with a particular conformation, so for example suspensory ligament problems are more likely with a straight hind leg conformation. Not suggesting your horse has this, but purely using it as an example). Also thermo-man mentioned bone fusion changes at the wither – is it worth asking him whether that might suggest the possibility of kissing spines?

Sorting the diet sounds good, whatever the problem turns out to be. But I’d go carefully if you opt for oil as it’s about 5X as calory-dense as hay, so if you feed 1lb oil, you need to reduce the food ration by 5lb hay!!! So realistically that’s going to leave the horse too short of fibre. Some people are very cautious about feeding oil because of the danger of developing insulin resistance and leaving the horse more prone to laminitis. If you do introduce it, worth doing it gradually and monitoring weight and condition score very closely.

I did try the Minnesota exercise suggestions with my boy, but it made no difference to him. But then he tested negative for type 1 EPSM on a hair sample, and showed no abnormality on biopsy, despite having a CK of around 3,500 (about 10 X the highest that a normal horse should have).

I did use Animal Genetics. Don’t really know much about them, but I remember reading online somewhere that one person had sent hair to them and blood somewhere else and the results came back the same.

Good luck.

Sarah
 
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Hi there,

My irish cob has EPSM confirmed - type I. I don't know what breed he actually is but I think he is ID cross...

Initially I had blood tests run as he didn't want any other horses to go near him, struggled to hold himself in canter, flagged after about 45 mins of exercise even walking, went through saddle after saddle thinking they didnt fit, was incredibly stiff for days after doing a bit more exercise though was fine during the exercise, smelly orangey wee, dropped off most of his body weight over night when had to come in at night...

Blood tests revealed high AST, and marginally high CK - he was actually tested after a week off (time off is one of the worst things for these horses), the AST remained raised after a week of 'rest' but went down when walked for 30 mins a day.
My vet didnt believe my suspicions because he had never tied up with me - so I contacted Dr Piercy at the RVC who has done quite a bit of research into PSSM. He & my vet chatted and he suggested the blood test (went to Minnesota) but I had actually already sent off the hair to Animal genetics then which I actually got back first - both came back with the same result. Type I heterozygous.

I had a years worth of blood tests monthly to determine what going on inside, and how his muscles felt on palpation (I am an animal physio) so I could correlate. They have not been outrageously high (AST & CK) but are a little raised uusually. I call AST the 'grumpy' enzyme as he is really really grumpy when this is up, but the CK is more variable but he doesn't seem as sore with the levels of this really.
AST takes 24-48 hours to peak. CK is 3-5 hours ish after exercise. (correct me if I am wrong, I have forgotten more about PSSM than have ever read!)

Things which 'set' his off PSSM are:
Staying in with no movement for longer than 5 hours
sugar changes in grass
no exercise
cold/wet
skimping on my warm up/warm down

I did an experiment when he was diagnosed and mine (they all seem very individual) was better with more movement and more grass, rather than less movement & no grass.
Ideally they should be out in a herd mooching round, but on no grass - which is virtually impossible!!

He tends to flag after about 45 mins usually of exercise. Warm up includes walking and loose trotting/slow cantering getting CV rate up. Can't ask for outline for about 15-20 minutes.

Food:
I have experimented alot with food!
He has been on Alfa oil
Any hay - soaked preferably
Linseed oil - now this is better than corn oil as the omega 3/6 ratio is better
He is also now on Alcar, micronised linseed too (micronised linseed instead of oil as he was getting incredibly fat and insulin resistant)
Vitamine E oil - natural source. 5000iu of this per day - this made a massive difference.

I just had a nutrition consultation from Dr Kellon in the USA as i was feeling a lack of 'energy in the tank' and I have to walk for 2 days after any time I canter basically to manage him. Have just started this so will see how get on!

If you PM me with your email address I can email you my 'factsheet' I have done for yard owner etc etc

The first step is to get him diagnosed properly so you know what you are dealing with... if he is ID x TB EPSM or RER could be possibles if it is a myopathy???
Best of luck - any questions please ask. There are also a few facebook groups which have quite a bit of info on them.
 
Thank you for both replies.

They are both very informative.

I am very keen to get the hair analysis back asap as he does certainly share some the characteristics you mentioned - but again could be caused by skeletal problems also. Simply don't know at this stage.

My boy doesn't 'tie up', as such. But, I definitely have to warm up very carefully. If I don't, his canter is even worse. I have to say, that it doesn't appear to tire after about 20/30 mins - he appears to lack energy and not be off the leg from the outset. But I must admit, I have got after him a bit - which now makes me feel very guilty!!

And, I don't think that I have run him for 45 mins straight without breaks only other than walking/trot hacking, but he will come back like he's crossed the Sahara!

I did read that the EPSM horse typically 'smacks' the ground with their hind legs and I'd been struggling to try to put the feeling into words until I read this! He tends to do this more with his right hind and is the most strange feeling in canter as he lifts you in the saddle and is totally unable to carry himself in either a straight line or circle in canter. Trot is much easier for him as he doesn't have to lift or round his back.

What you state about AST/CK is interesting. I would imagine that his last blood analysis for AST/CK would have shown some peaks/abnormalities [as vet said.] However, I have read that ID's very often show no elevation or only small elevations. However, his previous 2 blood tests did show elevations of AST (Liver enzymes completely normal so not worried about liver problems.)

Last night and this morning I fed him (small amounts due to introduction):
Soaked hay - approx 7Ibs.
Speedibeet - small handful
Alflafa pellets - again handful.
3rd cup oil - bought from supermarket - corn
Vits/mins - normal measure.

I was going to get larger dose of Vit E and selenium but not totally sure of ration yet, as I know you have to be very careful with it.

I am also concerned as I bought this horse to event!

Thank you for your posts.
 
Ah, Harriet! I'd forgotten, but it must have been you who told me about having the EPSM DNA test done in 2 different places! And I know I found your factsheet very helpful when you emailed it to me when I was first looking into my boy's problems......... so I'd definitely recommend taking a look at it.

Vitamin E can safely be fed at quite high levels apparently.

With selenium, if you are thinking of adding any selenium supplement over and above what's already in your vit/min supplement, then you really should test your hay/grass to be sure you are not going above a safe level. Probably I think I'd say that if you are feeding a full ration of a vit/min balancer, there shouldn't be any need to add any further selenium, though. Just not worth risking going into toxic levels of it.

S
 
Dear all

Finding this thread very interesting.

My daughter's 14.3 (no idea of breeding - came over from Ireland as a youngster) who is now 14 has been causing us problems.

He initially hurt his back badly in the spring, slipping in the field after the rain. He had physio, he went to camp, caught some sort of virus. Only discovered this when he became out of breath; sweaty; flanks heaving after jumping a round of show jumps. AST at 790; CK at 1400.

Brought him back into work over 6 weeks after a fortnight off. First time xc schooling, after 15 minutes started trailing back legs, unable to get over combinations. Bloods tested again 2 days later AST 789 CK 1400. Month off. Re-test was AST 730, CK 1111.

No other signs of EPSM. Only silight thing is that when my daughter (weighs about 5.5 stone) gets on him he is tense in his back for about 2 minutes then absolutely fine.

Waiting on blood test result for EPSM from America; booked physio in to see him as well. Bit worried re. Selenium as I am feeding him the NAF supplement (now worried that I am poisoning him with too much) - where do you get a grass/soil analysis done? - as well as Omega Oil. Otherwise he has a small amount of Healthy Hoof and hay.

Hoping that he just has severe muscle strain caused originally by the injury in the spring which he has exasperated by carrying on with the virus. She wants to BE him next year, so fingers crossed.
 
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All these descriptions of epsm horses sound like they are describing my boy to a T!!

He is now 5 and has been backed a year and a half and we still struggle to canter more than a long side of the school without breaking into a trot. He is stiff (particularly when coming out of his stable in the mornings) and walks with a stilted gait.

I have to say he did improve over the summer (warmer weather maybe but also coincides with changing him to a 'balanced diet'). I had his hay analysed and a diet plan writen which included 1 heaped mug of micronised linseed. I'm not sure If I can safely increase this without risking him getting too fat?! but that said I would hope that if I could get him more forward going I could work him that bit harder...

I have previously avoided feeding alfa-a as he suffered with very scurfy skin, which seemed to ease when I stopped the alfa-alfa but I'm wondering with the adition of the Linseed whether he may tollerate it a little better these days?

My added concern is that he is sensitive to grass sugars and has been verging on laminitic earlier this year, despite not being overweight (IR maybe?)

Any suggestions re diet?

He is currently on:
Micronised linseed
Fast fibre
balanced minerals
 
My horse was diagnosed with this, bloods were sent to the states, came back positive. The symptoms were serious tying up and sweating very heavily with any degree of work.
Well I looked into the diets etc and I could not feed him this because he is such a good doer and needed to lose weight, so what worked for us was low sugar, high fibre diet and the key is regular work and be sure to warm up and cool down. With this strategy we have not any setbacks at all for about 4yrs (Oh and I feed a daily electrolyte supplement)

I think his problem in reverse was being overweight, spring grass and this underlying syndrome. Good luck
 
Could I ask if permanently tight hamstrings would be a product of this too?

Sorry if I am way off the mark, but I have my suspicions about my mare who is also diagnosed with arthritic changes to the SI. It seems that many of the symptoms cross in a way. One thing we (my physio and I) have found from the start is extremely tight hamstrings. I already feed micronised linseed. Does keeping the horse very warm help too?
 
robthecob said:
Could I ask if permanently tight hamstrings would be a product of this too?

Does keeping the horse very warm help too?
Click to expand...

I would suggest they are linked... I would never keep a horse VERY warm... that would be uncomfortable for the horse, but yes, keeping him warm has helped my boy... also doing leg stretches after exercise and using an equillibrium massage pad too.

Just a note, My boy has been on ERS pellets for just over a week now and I have noticed quite a difference in his energy levels and way of going :)
 
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