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Equiseq pssm2 hair test

I recently got test results for pssm2 variant testing. He came back n/px if anyone is familiar with that!? He also has n/Imm. He is 4. Just curious if anyone has a horse with this. I think imm adds to px or causes px to be active so to speak. Can cause like a calm to crazy behavior change and then takes a while to calm back down again being muscles are contracted. Also causes twitching over shoulders and hind end if he gets amped up to much. I am changing his diet some and I have started lean muscle by immubiome after some great reviews from actual ppl. Just looking for more info on this!

Following with interest. Are you part of the PSSM Facebook page?

Yes I posted in there as well. Not much feedback tho.

Take EquiSeq testing with a grain of salt, as Dr Vahlberg has so far been unable to even correlate biopsy results with their hair testing results. But, it is still ongoing research.

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Yes and that’s why I put off testing pssm2 for couple of years bc of that and fact they are not validated yet but I just decided to just do it. But he is n/imm and that was not tested thru equiseq.

IMM causes significant and quick muscle loss after some “event”, usually vaccination. I have never seen anyone link IMM and PSSM of any variety - do you have any info on that?

The symptoms you describe aren’t that of IMM, but could be related to PSSM of some variety. Is he HYPP n/n?

They have been actually having horses with imm having symptoms like pssm. Some do some don’t. Some have muscle loss some don’t. He is tested for everything available genetic wise and only postive for imm and px

I have a suspect pssm 2 horse. I don’t know of any special diet that helps. I didn’t bother with genetic testing because I don’t think it is accurate and even if it was accurate, it doesn’t change the treatment options. The only thing that helps my mare is consistent exercise and extra protein in her diet. Not even certain the extra protein helps, but it doesn’t hurt anything.

They push u to test bc they say each variant requires something different so can’t fully help them unless u know which one or ones. But I totally get what your saying

The number one thing that helps my horse is very consistent exercise. She needs to be ridden 3x a week and kept moving. I think that helps more then any diet. I tried adding fat and really didn’t see any difference. Tried joint injections in case of lameness and that didn’t help either. The only consistent trigger for her symptoms is excessive heat. If it’s cool out, she’s nearly asymptomatic.

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Just a heads up but they’re no longer recommending high fat for pssm2/ MFM because it can increase oxidative stress. They’re recommending low fat, moderate NSC, and high protein nowadays.

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Ok, I did a little digging and didn’t realize this has sort of been recategorized. The muscle atrophy following vaccines (IMM) is one presentation, but non-exertional rhabdo is another

Phenotype: Myosin-heavy chain myopathy (MYHM) is a muscle disease in Quarter Horses and related breeds that results in two distinct clinical disease presentations. The first presentation is called immune-mediated myositis or IMM and it is characterized by episodes of severe muscle atrophy following an autoimmune event. The second is severe muscle pain and damage termed non-exertional rhabdomyolysis or “tying-up” that is not associated with exercise and may or may not have muscle atrophy.

Myosin-Heavy Chain Myopathy (MYHM) | Veterinary Genetics Laboratory (ucdavis.edu)

Correct, because PSSM 2 is not a glycogen storage myopathy, it is a protein metabolism issue of various types

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