Azoturia Triggers

Baby Girl tied up severely on Monday. The vet was surprised she survived. Her muscle enzymes were still off the charts 48 hours later and her potassium was extremely high. It was a really scary incident.

The scariest part if not knowing what caused this episode. Baby Girl is a very fit horse. She's ridden a minimum of three times a week for about two hours a ride, trotting and cantering with minimal walking. She was brought up to this level slowly and has comfortably when handling this kind of riding for several months without the slightest issue. She is turned out 16 hours a day and is very active in the pasture.

She isn't on a high grain diet. She gets three pounds of grain a day split between two meals. Her pasture is also good quality.

The ride that caused her azoturia was something I do all the time. 30 minutes, trot/canter with walk in between. The terrain was easy. Nothing about that ride was hard. This horse regularly competes in CTRs where we go 35 miles one day and another 25 the next, trotting almost the entire time, climbing mountains, and doing other challenging things. Nothing happened then. Why did that 30 minute ride cause her to tie up?

The vet guessed it was a genetic thing just coming into the light, but admitted it's hard to know for sure. I'm extremely concerned, because I don't want this to happen ever again...

I'm glad she's recovering! That must have been incredibly scary for you!

I don't know much but I have heard that a selenium deficiency can trigger/cause an episode of tying up...
I think I remember SorrelHorse having a mare that does that. From what I can recall, she keeps that mare on some kind of selenium supplement which I guess keeps the mare from having an episode...

A good point to start my search! Thank you!

Did SorrelHorse's mare do this suddenly without a change in diet? (I should PM her...) My mare has been on basically the same diet for two years. Maybe it takes a while for deficiency to show itself?

No problem!
I'm not sure. PMing her is definitely good idea. :)

I do know that selenium is one of those minerals the body stores (that's why it can be dangerous to overdose) so it seems feasible that she could have finally used up her body's stores of selenium. Unlikely, but feasible.
Another thought could be that she used to get some limited supplementation each summer from dirt/trees/the grass, something other than the food you give her, that she didn't happen to get "in time" this year...and (if selenium deficiency is the cause) an attack was triggered...
I'm really just spitballing here.

We've been in a drought all summer. The pastures aren't great. They're good, but not as amazing as in former years. Maybe that caused a deficiency.

Good thing I'm going back to the vet next week! I can bring this up with her.

Anyone else? :)

What is the breeding / bloodlines of this horse? Most metabolic problems are genetic, some can be tested for, but one really needs to know specific bloodlines or at least the breed(s) to know where to start.

Here's her pedigree!

Flash of Lightening Spotted Saddle

She's a Spotted Saddle Horse. She has a lot of TWH blood, but if you look back far enough to find saddlebreds, morgans, and standardbreds. Really far back there are even Arabs and TBs. Anything not TWH seems so far back it wouldn't matter much, right? I've never heard of a TWH with tying up problems...

These are not breeds/ bloodlines that I am personally familiar with. I do not know if they are predisposed to metabolic problems.

Did she happen to be in heat? I do know that coming in heat and being ridden hard can trigger it in some mares.

I would start her on a Vitamin E supplement and check out the possibility of a Selenium deficiency. [Just do not give her Selenium without knowing for sure she needs it.] I would also add an electrolyte powder to her diet when it is very hot or when she is going to be ridden hard, especially in the hot weather.

Did she get a bad enough case to pass black or dark urine? If she did, you could be looking at some serious muscle atrophy and damage. One of the main things to remember is to NOT exercise a horse that has tied up. It is best to let them lay down and be very quiet until muscle relaxers and fluids can be given. Just keep them wet down and cool in the summer or blanketed and warm in the winter, but let them be very still.

Thank you!

I researched a bit more. PSSM has been recognized in standardbreds, saddlebreds, morgans, and TWH.

She was not in heat at the time.

She did pass brown urine. The vet said her kidneys weren't damaged and there appeared to be no severe muscle damage. Thank God!

I will start her on a vitamin E supplement! I was going to start her on a multi- vitamin/mineral supplement anyway. Maybe I can find a combination.
EDIT: the stuff they have available as my small feed store contains Vitamin E (min.) 10,000 IU/lb. Is that sufficient?