By Dr. Steve Allday
Do your homework

Anyone selling an equine supplement can make nearly any outrageous claim and still sell their product legally.
However, the National Animal Supplement Council (NASC) is looking out for consumer interests. They ensure the ingredients on the label are the same as what’s in the bottle and do what’s claimed. They inspect the manufacturing facilities to make sure they are safe. If a product doesn’t have an NASC sticker, frankly, I’d put it right back on the shelf.
But, before you buy, have a good, long conversation with your vet about what your horse’s caloric intake should be daily, based on his age, activity level and muscle mass. Use this as your guide for feed. Have him checked for vitamin or iron deficiencies. Talk to your vet about the sort of supplements, if any, that your horse may need based on his stage of life and activity level. It will make you a more confident shopper.
Know what your horse needs daily
In my personal, professional opinion, there are not that many “extras” that a competitive horse needs daily. They deplete two things—the fluid that cushions their joints through repeated pounding, and their natural potassium and sodium through sweat.
Admittedly, I’m more than a little biased here, because I, myself, created a supplement, which I give to all my horses, every day, regardless of their age or racing status. It prevents them from needing as many injections for pain, actively prevents injury and keeps horses more flexible. I also believe you should supplement horses with an electrolyte solution, potassium and sodium daily to ward off conditions like “tying-up syndrome.”
There are plenty of feed supplement companies that advocate giving your horse daily supplements that boost calories and vitamins/minerals beyond daily limits. In my opinion, calorie supplementation will only get you one thing—a fat, slow horse. In a healthy horse, mega doses of vitamins won’t cause any harm, but they won’t do your horse, or your wallet, any good.
Will supplements help when your horse is sick?
Yes, but only under a vet’s direction. For instance, vitamin E, selenium, antioxidants and Morton’s Lite Salt are the prescribed cure for tying-up syndrome, which can cause widespread cramping and paralysis in horses.
Horses who are coming back after severe malnutrition or are suffering from a debilitating condition like chronic arthritis can also benefit from supplements made from colostrum, which provides a super punch of much needed vitamins and minerals. Your vet will have other recommendations for combinations of feed and vitamins to help a horse build up their stores again.
Those who’ve read my columns before know that I am a bit of a naturalist when it comes to horse care. I believe a horse should have as few performance enhancing injections as possible, and only take supplements when they are medically proven, through double-blind studies, to work. You can call me old fashioned if you want. I just call it good horse sense.