“What should I feed my horse?”

It’s a question that horse owners ask their farriers from time to time. The easy answer is, “Well, you need to feed a balanced diet.” Yet, a horse owner doesn’t always understand what that is.

“The good thing about a horse is that the way it looks on the outside is a direct reflection of what’s going on inside the horse,” Mike Barker of Life Data Labs told attendees at the 2017 International Hoof-Care Summit. “It tells us how nutritionally sound that particular animal is. And, not only is the outside of the horse an indicator, but the foot of the horse is an indicator, as well.”

Inadequate Diet

Whether a horse is overweight or underweight, has collapsed heels or crumbly horn, it’s an indication of a poor diet.

“We can either have a deficiency, an excess or a toxicity problem in either protein, energy — which I often refer to as calories — vitamins or minerals,” he explains. “If we have a deficiency or too much, then that creates an inadequate diet and that’s going to work on the outward appearance of the horse. It’s going to work on the foot, as well.”

Farrier Takeaways

The outward appearance of a horse directly reflects whether it’s nutritionally sound.

Too much of a vitamin, mineral or an amino acid can result in a deficiency
of another that’s vital to the horse’s diet.

An excess of methionine is often mistaken for white line disease.

Should a horse have a problem bran, calcium, phosphorous, magnesium, selenium, vitamin A, sulfur, methionine and zinc, they will manifest themselves in specific ways in the outward appearance of a horse.

Bran and phosphorous. When a horse is overfed bran, the feet literally begin falling apart.

“Bran is high in phosphorus,” Barker says. “When the horse gets too much phosphorous, it ties up necessary calcium. The horse is not able to absorb that in the hindgut.”

Calcium. This mineral is critical in the diet of the horse.

“Simply put, it’s the glue that holds that foot together,” Barker explains. “If the calcium’s tied up, we lose the glue and the foot falls apart.”

The calcium/phosphorous ratio that he suggests owners shoot for is 1:1, unless the owner is feeding mares or foals.

“Then we can go from about a 1½ to 2 ratio in a situation like that, because that mare and those babies need the additional calcium at that point in time for additional purposes, such as skeletal development and so forth.”

A horse that is deficient in calcium will exhibit broken up feet, as well as collapsed heels. Too much phosphorous can impede the absorption of calcium.Photos: Sue A. Kempson

Magnesium. While too much phosphorus interferes with calcium, a diet high in calcium will not affect phosphorous. However, too much calcium will hinder magnesium.

“Magnesium directly affects the nervous system, the metabolism and energy regulation of the horse,” Barker says. “It causes a host of problems there. Some of our horses that are a little antsy or a little on the wild side, so to speak, if they’re short in magnesium, that’s one of the key nerve regulators in the horse.”

There’s another potential problem with a diet deficient in magnesium.

“There are some links between magnesium deficiency and insulin resistance, as well,” he says. “Obese easy keepers often are magnesium deficient and insulin resistant.”

Calcium is the glue that holds the foot together …

Selenium. The element selenium can create a toxicity problem very easily.

“Five milligrams per day is our limit,” Barker says. “It’s very easy to exceed that, especially if you’re in an area that is selenium deficient, and the horse owner is feeding additional selenium — either in the feed or as a supplement. Another problem is that selenium will be present in the forage of hay, depending on where it originates and comes from.”

Selenium toxicity affects the hoof in several ways including lameness, hoof defects, poor hoof wall structure, horizontal hoof wall ridges or cracks, crusty coronary band, hoof wall invasion by bacteria and fungi, and it replaces sul­fur in the hoof.

Selenium toxicity results in poor hoof wall structure, horizontal ridges or cracks, a crusty coronary band and invites invasion of bacteria and fungi.

Vitamin A. It’s important to balance the amount of vitamin A in a horse’s diet.

“This is rather unique in itself in that, we have the same clinical signs whether there is a deficiency or a toxicity problem with vitamin A,” he explains. “The end of the hoof wall literally falls apart. It looks like there are hair-like projections that are sticking out the end of the foot itself. So, our goal is no more than 10,000 units of vitamin A on a daily basis.”


For more valuable insight on the role of nutrition in hoof health, check out Hoof Nutrition Intelligence by visiting

Sulfur. As with bran, calcium and selenium, an owner must balance the amount of sulfur in a horse’s diet to avoid interference with the absorption of another trace mineral.

“Sulfur is very easy to cross the line with, especially if you’re feeding the horse a hoof supplement and a joint supplement separately,” Barker says. “A lot of times, that’s too much when you combine the two. It can affect the strength of the hoof wall, as well as compromise copper in the diet.”

Methionine. An essential amino acid, methionine is vital for the health of the horse, yet toxic when consumed in excess. Performances horses that are receiving a good quality diet, as well as supplements containing methionine are likely candidates for methionine toxicity.

“The kicker with methionine toxicity is that the horse will have progressive degeneration of the horn spreading outward from the white line,” he says. “So we’ll often mistake a methionine toxicity problem for white line disease.”

Signs of vitamin A toxicity or deficiency include poor hoof wall quality, as well as hair growth from the hoof wall.

Methionine toxicity also causes a depletion of iron, copper and zinc.

Zinc. A lack of zinc in a horse’s diet will be evident in the growth and appearance of hoof wall.

“Not enough zinc leads to rapid hoof growth — it will need to be trimmed every 10 to 14 days,” Barker says. “We’ll have plenty of hoof growth, but it’s very poor quality of keratin in the outer layers. It will be brittle. Another indication of a zinc deficiency is the horse will be more susceptible to canker, as well.”


April 2017 Issue Contents