When I look at the various calming supplements people mention, all of them except for the Zylkene (milk protein) and the Shen Calmer (herbal blend) are based on magnesium. My reference book suggests magnesium citrate is the most bio-available form. And as others have noted, there absolutely can be individual reactions to deliberate overdoses of magnesium, though apparently it is not particularly dangerous.
If I felt that my horse’s behavior might be the result of a magnesium deficiency, here I think is how I would proceed.
First, I would crunch the numbers on my hay, grain, and mineral/vitamin supplement to see if there was a deficiency “on paper.” That would require getting the hay tested, and e-mailing the feed mills for the nutritional break down of the feeds, or using FeedXL if the feeds were on that database.
Second, I would crunch the numbers of the other minerals in my feed, to make sure I wasn’t going to throw other minerals out of whack. At this point I might phone the very helpful nutritionists at my local farmer’s co-op!
If there was an obvious deficit of anything on paper, I would make sure that deficit was remedied.
If there wasn’t an obvious deficit on paper, I would focus on the more obvious elements of energy management first. Does the horse get a chance to gallop around with no rider on a regular basis, or is “turnout” just standing in a dry lot with a hay net watching the world go by? I would make sure the young horse had a chance to get the wiggles out every day. If that didn’t fix the problem, I would cut the diet back to just plain grass hay for a few weeks, plus a scant handful of whatever you need to carry the regular vitamin/mineral supplement. At the same time, I’d be doing intensive ground work to address the spookiness. If I didn’t know where to start, I’d find a good-natured western trainer to help me, a common-sense sort of person, not an acolyte of one of the more programmed programs.
One of the posters above made the really good point that you want to horse to look to you for advice when something alarming happens, not just high tail it out of there.
If increasing the work, decreasing the concentrated calories, and doing some “training for courage” didn’t help, then it would be time to see if magnesium would help. As one of the posters pointed out, you don’t have any guarantee what’s in any given supplement. So I would try to find food or human or pharmaceutical grade magnesium (as I said, citrate seems to be the most bio-available) and figure out the right dosage, and try that for a few weeks, watching carefully, and not changing any other factor. Since magnesium seems to be a low-risk additive, I probably wouldn’t bother with a blood test, just try to see if it made a difference.
Of course, by that time it would be spring, and the change in weather by itself could easily make my hot horse much calmer!
But one thing I wouldn’t do, would be trying out different brands of magnesium-based calming supplements, because they all have the same ingredient, and if one doesn’t work on your horse, the others won’t work either.
Of the other supplements, the Zylkene milk protein sounds intruiging, because there seems to be some clear scientific evidence that it works cross species. I am leery about the Shen Calmer, though, because the explanation for how it works does not fit my understanding of how the body functions.
My own horse is not hot, but when I reflect back on my time with her, it’s been fairly obvious how to manage her energy levels. When I started riding her, she was six, and we had some bouncy bouncy moments that made me nervous. We cut back her oats, I longed her before I rode, gave her buck and run turnout with her buddies as much as possible, and tried to work her every day. The past year or two, I’ve wanted her to have more energy, and have found that she is a different horse if she gets four rides on, one day off, and more oats. I know all the nutritionists say “oats don’t make horses hotter,” but most people’s experience is that they do, and thank goodness for that, I say!
But I also have to say, that I don’t think that a horse being “hot” means that it is unhealthy, unhappy, in pain, or has a nutritional imbalance. Absolutely the opposite! Horses are “hot” when they are healthy and feel full of themselves, and unless their “hotness” is getting them punished by their riders, they are really happy when they are hot, especially if they are running loose in a place they can really bolt and buck and squeal. You don’t want all of that under saddle, agreed.
And some horses are too hot for some riders. I don’t have a young OTTB, for exactly that reason. I’ve watched too many riders at our barn come to grief with them; there just isn’t enough room; when the horse gets wired to the point that the owner is afraid to handwalk him down to the attended turnout arena, things do not go well. And a calming supplement, in the absence of intelligent management or the right horse/rider match, is not going to have much effect.
