Yesterday I took off from work early in order to get a ride in my new mare Jewell while we had a day of warmer temperatures and bright sunshine.

My neighbor has been giving my musician husband riding lessons. I saddled up to go join them in her arena. Jewell was looking around as usual, then spied the mechanical gate walker used at Kentucky Equine Research to exercise the horses used for nutrition research. The fast movement of several horses and the mechanical noises had her on edge.

I walked her and stopped several times so she could see it from several angles, then entered the arena and walked her around there to see it again from that angle.

Then a couple of other research horses were turned out with full muzzles (they can't graze, but they can drink and get exercise). I'm sure they are a strange sight to an unfamiliar horse.

We worked, but Jewell was reluctant to move forward off my leg. Since we are still learning each other, I assumed she was just being obstinate. I should have known better.

We didn't work hard or long, but when I finished, she was very sweated up and seemed to be moving a little stiff. I dismounted and the first shadow of "Uh oh" creeped into my dull brain.

Was Jewell tying-up?

We had to walk home (I was leading her), and we took it very slowly. It wasn't far. She was stiff, her respiratory rate was higher than it should have been, but she didn't seem in excess pain or refuse to move.

She was sweaty and her respiration rate was still higher than it should have been when I made it home. My husband and I toweled her off as I didn't want to walk her to cool her out. I watched her for a while, still wondering if I was correct about my lay diagnosis. I turned her loose in the dry lot just to see if she still was moving stiffly, and she was. She loves to roll, so I put out a big pile of fresh hay to tempt her if she wanted to lay down. She wanted to, but didn't. When she postured to urinate and was almost too stiff to be able to posture, time to call Dr. Carol McLeod.

After going over clinical signs, Dr. McLeod said she'd be there in 30 minutes.

Her notes said: Mild tying-up. Heart rate 44. Respirations 32. Splinted abdomen (trying to hold muscles still so they wouldn't hurt), but muscles were soft (often horses that are tying-up have rock-hard muscles). Eating hay slowly. Mucous membranes were pink and moist.

She treated Jewell with IV Bute and Banamine, and said she'll come back mid-morning today to see how she is.

I covered her with a fleece blanket to keep her muscles a little warm in the cold night air at Dr. McLeod's suggestion (I don't have a horse blanket--yet). She didn't drink while I was there, but she was eating hay.

At 3:30 a.m. I convinced myself that going down and bothering them wouldn't be any help. At 6 I couldn't wait any more (and usually I'm at the barn by 6:30 anyway). She walked up normally, and she immediately started in on the hay I put out.

Now let me go back to last night after I had tucked Jewell in for the night.

I talked to Dr. Joe Pagan, one of the leading equine nutritionsts in the world. This mare was not a nervous sort (what we typically see in Thoroughbreds that tie up). My daughter had ridden her solo and with strange groups of horses over all types of territory. She'd worked her 20 miles in one day herding cattle.

He told me of an unpublished study by Dr. Stephanie Valberg of the University of Minnesota, one of the foremost researchers into polysaccharide storage myopathy (PSSM). Dr. Valberg had traveled out west and tested a large group of Quarter Horses for the genetic defect that causes PSSM. She found while quite a few had the defect, none showed clinical signs. The assumption was because of the low-carb diet that most of those horses lived on; dry pastures and alfalfa hay (which is low in structural carbohydrates).

I know the grasses in Kentucky have high sugar content. And our hays here are the same.

So, I sent an email to Dr. Valberg last night and I'll talk to Dr. McLeod today. We'll test Jewell and see if she carries the genetic defect for PSSM. Then we'll make our decisions from there.

For me, while it's only been two weeks, I've fallen for Jewell. I hate the thought of dry lotting her for the rest of her life here in Kentucky, and I hate the thought of having to give her up to go live back out in Wyoming with my daughter.

Anyway, here are a couple of articles on PSSM. TheHorse.com has lots more information, but I thought this might help you as it helped me.

AAEP 2008: Genetic Diagnosis of Polysaccharide Storage Myopathy

Researchers Examine Effects of Hay Carbs on PSSM Horses

Those of you with PSSM horses, what are your management options in case this is the problem?