I was just replying to your comments when I got some test results that changed my thinking.
Instead of a long reply in the comments I'll just say that I really, truly appreciate all of the thoughts, opinions, experiences, and support that I get from all of you through your comments. It really is a big help.
So Tonka's EPSM results just came back. He is positive - P/N - which means he has one copy of the EPSM gene. Good thing he's not a breeder because he'd have at least a 50% chance of passing it on.
They also recommend another genetic test to see if he has another problem, malignant hyperthermia, that would possibly cause death under general anesthesia. General anesthesia is when they put them completely out, is that right? It wouldn't be the same as when they just get their teeth floated?
Which brings me back to the idea of surgery. If he does have something wrong in his abdomen that requires surgery, I am not going to do it. Whether or not he could survive general anesthesia, it makes no sense to put a horse who already has a severe muscle disorder (worsened by stress) through a surgery. It would be unfair to him and it would be a bad monetary decision.
I'm really upset, as you can imagine. I feel like crying and cussing all at once.
Funny, I knew he had EPSM, I expected this result, but I hadn't thought about it in quite this light before.
It could be that all of his problems are caused by EPSM and I'll be able to get him back in shape and feeling good again. I hope that's the case. I don't think it is. I know it sounds negative but I really feel like there's something else going on here.
I will continue to do diagnostics - check for beans, check his teeth, maybe a rectal exam, talk about bloodwork specific to some issues that could be causing a problem - but we won't be doing anything heroic.
Another annoying factor is that I can't get him to eat his special diet that is supposed to make him feel better. I've been tweaking it this way and that way, trying to make it more enticing, and he just doesn't finish his feed. I'll keep trying...