by Juliet M. Getty, Ph.D.

Horses are complex animals, and correctly meeting their nutritional needs can be challenging. We all have our horses’ best interest at heart, but it is easy to understand how feeding misconceptions can occur. Here are three not-co-commonly held myths.

Myth #1:  Horses don’t need as much hay during the night because they sleep.

Horses are awake and moving virtually all the time. Mature horses will sleep up to two hours per day, broken into short periods. These 15 to 20 minute naps are intermittent throughout the day and night. In other words, horses do not sleep for any length of time like other animals do. Being prey animals, horses’ sleep must be taken in frequent breaks of short duration, ideally in a group situation where some take turns resting while others remain alert for dangers.

And here’s why they need to have forage (hay and/or pasture) available all of the time, day and night:  Horses are trickle feeders, designed to graze continuously to keep the digestive system functioning normally, thereby preventing ulcers and colic. Feeding them in sync with their natural instincts and physiology requires that they have forage available any time they want it. 24/7

The way you can determine how much hay to feed at night is to make certain that there is some hay left over in the morning. If your horse runs out of hay and you wake to find him kicking and pawing, he is hungry. But more than that, he is in pain (due to the acid bathing his stomach) and he is mentally stressed. This stress can lead to a multitude of health problems and, ironically, it can prevent an overweight horse from losing weight. You can ease your horse’s discomfort by giving him more hay than he could possibly eat during the night. Once he realizes that the hay supply will never run out, he will start to self-regulate his intake and actually begin to eat less than he used to because he has calmed down, both physically and emotionally.

Myth #2:  The horse’s stomach should be empty while exercising to avoid digestive upset.

We don’t feel comfortable exercising after a large meal and we therefore assume that our horses don’t either. But define a “meal.” We generally think of feeding a commercially fortified feed—something that comes out of a bag. Or we may feed a meal of oats along with supplements. And you’re right: This type of meal that is low in fiber and high in feedstuffs that provide starch, protein, and fat should not be fed immediately before exercising your horse. But forage should! It’s just the opposite—restrict forage before exercise and you’ll produce, rather than avoid, digestive upset. Here’s why:

The horse’s stomach, unlike our own, secretes acid all the time. That’s right—it never stops. Chewing produces saliva, a natural antacid. But when the horse is left without anything to chew, the acid will accumulate in the stomach and settle along the bottom (as water would in an empty jar). The lower portion of the stomach (the glandular region) has a protective mucus layer, but the upper squamous region has no such lining. Ask your horse to move, and the acid sloshes around, reaching the unprotected area, leading to an ulcer. And, as the acid flows through the small intestine, cecum, and large colon, it can cause further damage along its path, potentially leading to colic and ulcerative colitis. 

Allow your horse to graze on hay or pasture before asking him to move—15 minutes ought to do the trick. You’ll not only keep him healthy, but he won’t be in physical and mental discomfort, making him more relaxed and receptive.

Myth #3:  Electrolyte supplements meet the horse’s salt requirement.

Your horse sweats more during the summer and drinks less during the winter, making electrolyte supplementation worth considering. But electrolytes alone will not stimulate your horse to drink more water—and water intake is critically important to ensure proper digestion. To encourage drinking, your horse needs to have enough sodium (salt). A balanced electrolyte supplement is designed to replace what is lost from perspiration, but electrolyte supplements should only be given to a horse that is already in good sodium balance. There are several ways to accomplish this. The best ways include offering free-choice granulated salt, or adding salt to your horse’s meal. A white salt block or preferably, a natural salt rock, will help, but many horses do not lick them adequately.

A full-sized horse requires at least one ounce (two level tablespoons) of salt each day for maintenance, providing 12 grams of sodium. This is true all year long, even during the coldest winter months. Heat, humidity, and exercise increase the horse’s need. Horses often will not eat extra salt, so consider syringing one ounce of salt mixed with some oil or flavored liquid after an hour of intense sweating, not to exceed 4 ounces per day. If your horse is working for several hours at a time, you can add an electrolyte supplement but it should be offered in addition to salt, to replace what is lost from perspiration.

In order to prevent ulcers, always allow your horse to eat something before giving him salt or an electrolyte supplement. And never add electrolytes to a horse’s only water supply — this will interfere with water intake. Fresh, clean water should always be nearby.