Choosing the Best Supplements and Nutritional Mix for Your Horse

A?frustrated fellow horse owner said that choosing from among the thousands of feeds and supplements available was like trying to hit a distant balanced-ration bull?s eye with a shot gun ? you just keep shooting and hope something eventually hits.

SHe’s certainly not alone. We’ve all been guilty at some time or other of just firing away at our horse’s feed tub without knowing if we were even facing in the right direction. As one of the worst offenders, I’ve been asked to share my story with the hope that you can learn from my feeding adventure.

I started breeding horses in 1974. Back then, nutrition rules were simple: Keep the calcium to phosphorous ratio above 2:1 and put out a salt block. That was it. Ignorance was bliss.

Naturally I wanted to give my horses the very best, so one of the first grains I chose was Stampede from Blue Seal, an 18% protein sweet feed. It was probably

Trilby, at age 17 (top), displayed the characteristic thick crest and fat deposits of insulin resistance. At 18 (bottom), she showed the physical improvement from a balanced hay ration.

a?perfect feed for whippet-thin endurance Arabs competing the Tevis Ride, or racing Standardbreds undergoing intensive interval training but not for my Morgan horses.

The product practically dripped molasses ? open a bag and flies from neighboring states headed your way. But that protein level sucked me in. I had young horses, and I just knew they needed that much protein in their grain. I also threw in 25% protein Calf Manna for good measure.

Did I consider the protein being supplied by my hay and pasture’

Of course not. That was just ?roughage? or ?something to keep horses busy.? Disregarding the nutrition in forage was universal back then.

Three decades later I learned the protein requirement for a four-year-old horse is 630 grams/day. Even 22 pounds of relatively low 7.5% protein hay easily supplies 698 grams. I learned this after 30 years of my horses happily and efficiently passing that excess protein out through their urine. No wonder my stalls always reeked of ammonia. And let’s not even discuss wasted money.

There were only one or two equine supplements available back then. The most widely used was Clovite, which contains a lot of vitamin A with a few other vitamins added in. Of course, I had to have that as well.

I never knew that my horses were getting generous amounts of vitamin A from their green pasture, their hay, plus their grain. Doing the math now, I realize how dangerously close I was treading to toxicity levels.

In my defense, I did occasionally come close to the mark. When kelp supplements became the rage, I jumped right on the bandwagon and added Source to my ration. The product was irresistible. I fed it for years until I was visited by a friend who raised her eyebrows when I proudly bragged I had all my vitamin and mineral bases covered. ?Really,? she said. ?I see it supplies beryllium, lithium, cesium, boron and antimony, among others. What exactly is the horse’s requirement for those’? I was speechless.

She patted my hand and said, ?It actually is a very nice source of iodine, dear.? Wonder of wonders, I really did need to supplement the iodine, living in a region where the deficiency is widespread. Even a blind pig finds a truffle once in awhile.

Bring On The Fat

The ?80s and ?90s saw an explosion of equine supplements. I’m sure the manufacturers were ecstatic when they start tapping into a huge pool of uninformed consumers with money to spend . . . like me. In 1991 alone I fed: Agway Trim, Calf Manna, Bloom, Select II, Vitamin E & Selenium, Gen-O-Hoof, All-Tech?s Yea-Sacc, cracked corn, sweet oats, and Omolene 200. Then came Athlete. I had to have it.

Athlete was Purina?s new extruded fat supplement. According to the equine grapevine, fat would solve all our problems ? coats would shine, thin horses would fill out, fat horses would have more endurance, barren mares would all get pregnant. It was magic. $30 a bag’ Sign me up.

Up until now, my horses had remained healthy. I escaped problems for years because I started with young foundation animals and I kept them bred. When they weren?t nursing foals, I was riding them ? a lot.

Favorite and Toast on a dry lot, consoling each about about their sore feet.

By the ?90s a hat trick of circumstances finally caught up with me: My original mares were passing middle-age, I was no longer riding the older horses, and I introduced fat into my feeding program. It is now well-established that fat contributes to the development of insulin resistance in other species. A recent study demonstrated that a single intravenous dose of fat can cause insulin resistance that persists for up to a week. And that was in normal Thoroughbreds. Imagine what it did to my Morgans.

The Laminitis Years

By the late ?80s, most of my herd exhibited all the signs of what we now know to be insulin resistance (see sidebar). None was fed more than a pound of grain a day, even though that was probably 1/8 of the amount recommended on the bag.

In the winter of ?92 laminitis struck its first victim on my farm: my darling babysitting pony. I was stunned. One much-quoted study had come out stating laminitis was caused by fructans in grass, but my little Toast was being fed nothing but hay and a handful of grain. How could she possibly have laminitis’ Three months later a former show mare came mincing in off pasture. Radiographs showed laminitis and 5 degrees of rotation in both front feet ? clearly foundered. I wanted to smack myself. Why had I ignored the first shot over the bow when the pony went lame’

My vet wasn?t much help. He told me to start all the fat mares on a thyroid supplement and to cut their hay way back. I knew a severe diet restriction was not the answer. It would force the horses into starvation mode and just reset their basal metabolism at an even lower level, keeping them fat on even less food. The vet also never mentioned restricting pasture time.

This was well before grazing muzzles became available, but with 30 acres of fenced pasture, I could not resist turning out my horses for at least part of the day; unfortunately, they paid the price for my lack of backbone. He also never advised me to restart the iodine, essential for normal thyroid functioning and metabolism. Giving a thyroid drug to a horse deficient in iodine is like stomping on the accelerator of a car that has no gas in the tank.

Throughout the ?90s, I stayed in the same unsuccessful pattern ? tiny amounts of grain, untested hay, and a smorgasbord of supplements. Exercise was hit and miss. I figured I was safe turning out the problem horses on over-grazed paddocks. In spite of my good intentions, I was now up to five horses with at least one attack of laminitis.

Ironing Out The Problem

In early 2000, I contacted Cindy Foley, editor-in-chief of Horse Journal, about a minor concern. She not only graciously replied, but also asked me about my horses, their health issues
, etc. She put me in contact with the magazine?s veterinary editor, Dr. Eleanor Kellon, who was starting a field trial on the use of chasteberry in the treatment of Cushing?s disease, as my foundation mare was a candidate for the study.

Over the next year we had many email exchanges, and Dr. Kellon became aware of my problems with laminitis. I told her I’d now switched to Triple Crown Lite, the first low-carbohydrate feed to come out but still had laminitis flare-ups. Dr. Kellon suspected my insulin resistance might be driven by the high iron levels in my geographical area.

Iron overload had long been known to worsen insulin resistance, but it had also just been implicated for its pro-inflammatory properties; in other words, it encourages any disease condition ending in ?itis.? The ones most significant to horse owners are tendonitis, osteoarthritis, uveitis and my dreaded laminitis. I knew iron had been removed from adult human vitamin formulations, but it seemed to be present in every equine supplement. Dr. Kellon said the only way I’d know for sure was with a hay analysis.

Huh’ it’s just roughage! She pointed out I was feeding 20 pounds of feed to each horse every day, at least 90% of which was hay, and I was totally ignoring the nutrition it supplied. She was firm, so I scuffed into my local feed mill and asked if they had any idea how to test hay.

The two guys behind the counter burst out laughing. ?We’re not going to let horse owners start testing hay,? one snorted. ?We make all our profit off you saps buying everything new that comes out in a shiny bag or bucket.? The other guy strolled into the back room and came out with a hay probe. He grinned, ?You snotty horse people make fun of dairy farmers in their flannel shirts and suspenders, but they’ve been testing their hay for over 20 years!? He showed me how to core the bales and told me how much to bring in. The mill had a contract with Dairy One (877-819-4110 or You can also get hay tested through Litchfield Labs (517-542-2915 or

As predicted, the iron level in my hay was hugely elevated. Dr. Kellon balanced my hay with a targeted feeding program that now included some single minerals, like magnesium oxide, salt and iodine, as well as a couple commercial low-iron products. She informed me there was no ?silver bullet? supplement that would remove the excess iron the horses were currently storing, in spite of the claims in herbal catalogs. She said if I continued to feed a tight ration based on my hay analysis, the imbalances would eventually correct over time.

I also took the final steps to defeat insulin resistance for good: I muzzled my at-risk horses during turnout, and I made sure every adult horse met the minimum exercise requirements: 30 minutes a day at double the resting heart rate four to five times per week.

A Sharpshooter Is Born

My last incidence of laminitis was a few months after I’d started my targeted ration in 2002. I’d love to tell you miraculous things happened, but they didn’t. My entire herd is sound and healthy. The first foals raised on the balanced-forage diet are now 5. Yes, they are bigger than their earlier counterparts. I can see my reflection in their hoof walls and they’ve got tendons like harp strings. Of course, it can be argued, they may have turned out that way anyway.

I get almost ill thinking of those earlier years. Not only did I waste an enormous amount of money, but I harmed my horses by my ignorance. There was nothing wrong with anything I was feeding ? they are all top-of-the-line supplement and feed choices ? but throwing everything at my horses really was killing them with kindness.

Beth Benard is a

Horse Journal Contributing Editor. She raises Morgan sport horses on her Canequin Farm in Rome, N.Y.

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