I'm relatively new to the world of horse care. It seems to be taken as an article of faith that horses need to be on supplements.
To be honest, some of this stuff seems like a throwback to a darker age... "raspberry leaves... garlic... fish extracts...eye of newt..." I've started to wonder, is there any evidence proving that these work (and do no harm)?
It seems like even people who would not use folk remedies and herbal supplements for themselves will give them to their horses (?)...
What do you think? Is there a source you rely on to see if there is research backing up these supplements?
Biotin for hoof growth and quality is one of the few supplements that has excellent research (double-blind, replicated) to back it up. 20 mg per day. I feed Uckele Hoof Biotin, which works out to around $10 a month.
There was a University of Georgia study on the effect of yeast on digestion of low-quality roughage (positive effect).
Vitamin E has been shown to degraded quickly in hay, and natural Vit E is more bio-available than synthetic. The bio-availability may be drawn from human research, though; I can't remember that part. There have been some studies (OSU, etc) on Vit E and some neurological conditions. Extra supplementation helped... because the neurological horses were Vit E deficient to begin with. Not because extra Vit E is a magical neurological cure-all, as far as I could ever find.
I never could find anything conclusive on MSM in horses, although I will admit I am one of the ones who swears by it anecdotally for a particular issue with my mare.
IIRC, I did find some solid information on magnesium and muscle relaxation. However, I think the conclusions that can be drawn from that get twisted to an extreme when it comes to mag-based supplements and what they are marketed for. That includes raspberry leaves.
There's more information out there than I thought there would be when I looked into some various things. But there's not nearly as much as the supplement industry wants people to believe, and what research I could find did not prove what the marketing departments wanted me to believe.
That, and any bucket of supplement you buy does not have to actually prove that it contains what it says it contains. It could have just flour, aspirin, or other drugs in it that may be causing the positive effects you are seeing, but may also show up on drug tests, or cause adverse effects in horses sensitive to those drugs. Just like those natural penis enhancing supplements- most of them contain viagra or cialis!
With few exceptions, like the biotin studies, not much.
If there are any, most of the research involves small samples & not many replications, if any. Further, matching the dosing/combos in a study with the actual supplement you buy doesn't seem to happen a lot, either.
There is very little research on equine supplements. And I looked very hard for a time.
I think the initial and ongoing reason was/is lack of funding. But also, horse owners believe they are doing a good thing by buying various stuff, making it too risky to do research. Why risk failing to prove something works, when people are buying it anyway? Good science is sometimes bad marketing.
It is well known that negative findings are often not published. I wonder how many supplements have been proven ineffective, and the studies quickly buried and forgotten.
Unfortunately, this will continue as long as there are no government regulations for proving efficacy. Not that I like regulations, but sometimes they work.
If your horse has no problems, you need nothing. If he DOES have a problem as determined by a veterinarian, do what the vet recommends. Supplements are a fad right now, mostly among people who swallow the same kind of marketing that sells cosmetics and AbMasters. No science worthy of the name has ever "proven" they are even beneficial, let alone necessary. Save your money.
I am not one to go out and buy the latest fad in supplements. BUT........I have found MSM and a very inexpensive brand of Glucosamine to be very helpful, and have actually watched my horses nibble on raspberry leaves when there was plenty of grass etc. to chose from, but only at certain times of the year, mostly in the spring.
If I withdraw the MSM or Glucosamine, I see a real difference, a deterioration in movement and comfort in two of my elderly horses.
I am only going by my own personal observance and not any statistics or advertising.
I know that glucosamine/chondrotin was proven *not* to work in humans (thought this finding hasn't stopped lots of people from taking it).
That makes me skeptical of whether it would work any better in horses...
Horses and humans have vastly different alimentary systems and utilize foods very differently. It is not at all true that what works (or does not work) for one species is going to work for another.
If you're referring to the article published in the New England Journal a few years ago, I believe the conclusions were that it did not appear to reduce pain significantly in all comers, but that a fair number of individuals did experience some pain relief.
Given the fact that it is not really a pain reliever, I'd say the study, while well done, leaves lots of questions unanswered.
All in all I remember thinking, when this came out: "Meh, seems to help some people a little, and is pretty darn safe". Which is precisely what I tell anyone who asks me about it.
I haven't reviewed the veterinary literature in detail, but IIRC these products do seem to work OK in canines, no? And not so very well in equines? Perhaps it has to do with what each species utilizes as a food source WRT how well they can absorb and utilize the glucosamine and/or chondroitins (which are two vastly different things although frequently combined).
The confusion led the National Institutes of Health in the U.S.A. to fund a large, multicenter clinical trial (the GAIT trial) studying reported pain in osteoarthritis of the knee, comparing groups treated with chondroitin sulfate, glucosamine, and the combination, as well as both placebo and celecoxib. The results of this 6-month trial were published in 2006, and the publication explained that patients taking glucosamine HCl, chondroitin sulfate, or a combination of the two had no statistically significant improvement in their symptoms compared to patients taking a placebo.
That was enough to stop me from taking the big pills I didn't enjoy taking anyway!
Of course, it's true that horses are different from people. But in general, I think we want to see evidence that a substance works before we start feeding it to human or animal... so back to my original question, what evidence is there for a lot of these supplements?
I'm especially curious about the calming supplements... since my daughter's mare nearly unseated her yesterday with the big sideways leap (who knew she was so agile?!), I'm thinking how nice it really would be if there was a formula for making a horse mellow!
That is the same study I cited. If you want to harvest a different chunk out of the actual study's abstract and spin it hard in the other direction, you could say this and be absolutely accurate:
For patients with moderate-to-severe pain at baseline, the rate of response was significantly higher with combined therapy than with placebo (79.2 percent vs. 54.3 percent, P=0.002).
It does pay to read the whole thing, to be wary of third-hand digestion of medical research published in the lay media, and to not just harvest bits and pieces, and to understand study design. This trial set as its definition of "success" a 20 percent reduction in perceived pain. So a fifteen percent reduction would be a FAIL in terms of the study, although to the individual sufferer a 15% reduction might be pretty good.
The conclusion drawn by most experts about the GAIT trial was that glucosamine/chondroitin can have modest benefits in some individuals, mostly those with significant pain and the benefits do not come in the form of huge and miraculous relief but rather that "it helps".
My conclusion based on that study is that there might be some benefit in some individuals. Certainly not enough to add it to the drinking water or for everyone under the sun to start taking it immediately, but not enough to reject these (safe, cheap) things outright, either.
I'm thinking how nice it really would be if there was a formula for making a horse mellow!
There is--a soaking wet saddle pad, removed daily.
It is a big, fancy, elaborate handful of anecdotes.
No control group, no blinding, no standardization of either diagnostics nor response to therapy.
Pretty useless, unfortunately. But I applaud the author for writing up her observations. What a small study like this OUGHT to do is provide the impetus for more research, done properly and with the proper controls and efforts to eliminate bias and the "mischief of small numbers". A placebo group would have been SO easy to add on to the studied subjects in this case!