By: Dr. Sarah Carter
Horses are herbivores and have a specialized gastrointestinal tract to digest and absorb nutrients from plants.
Importance of Cheek Teeth
They have two rows of “cheek teeth” that they grind side to side to break down the tough plant material in their feed. These teeth can develop sharp edges if not ground evenly that become painful when a horse tries to eat. Our team will check your horse’s teeth annually to see if they have sharp edges that need to be ground down during a procedure referred to as “floating.”
Stomach Size and Feeding Habits
Horses have relatively small stomachs that are designed to process small meals throughout the day and night. They are not adapted to large meals followed by long periods with no feed. Feeding large meals 1-2x/day can lead to ulcers in the stomach lining.
Intestine & Colon Function
Their small intestines are very similar to those in humans, absorbing any easily digested proteins, fats, and carbohydrates.
The large intestine in horses is broken into two sections, the large colon and small colon. The large colon contains lots of microorganisms (bacteria, protozoa, and fungi) that help breakdown the harder to digest parts of plants through fermentation. The horse is then able to absorb and process the products of fermentation. The small colon absorbs residual fluid and produces fecal balls.
The Role of Microorganisms
It is important to maintain the microorganisms in the horse’s colon for overall GI health. These microbes form a mini ecosystem that must be balanced. Feeding too much grain can lead to excess acid production and changes in the pH of the colon. This can kill the microbes that live there and lead to colic, founder, and diarrhea.
The Basis of a Horse's Diet
The basis of any horse’s diet should be forage. This means pasture, hay (including hay cubes), or a pelleted complete feed. Many horses that are not growing, pregnant, lactating, or doing heavy work can be maintained on a high-quality forage alone (would need a ration balancer with vitamins/minerals added). A good place to start is 1.5-2% (15-20lbs for average horse) of a horse’s body weight in hay a day or 1.5-2 acres of pasture per horse.
If you are not sure about the quality of your hay, you can have it analyzed for nutrients.
Concentrates for Additional Energy
Horses that need additional energy beyond forage to maintain adequate body condition can have additional carbohydrates or fats added to their diets in the form of concentrates. This includes oats, sweet feeds, and commercial grain mixes. When adding grain to a diet, it is very important to do so gradually so a horse’s GI tract can adapt to the change. Grain should never make up more than half of the horse’s diet and should ideally be kept as minimal as possible. Some horses do not tolerate excess carbohydrates well at all and would do better with fat supplementation in the form of added vegetable oils to the diet.
Managing Weight: For Heavy and Thin Horses
If your horse is too heavy, start by gradually cutting back on any concentrate they may be getting and remember that some horses do well on forage alone. Some horses even get heavy on forage alone and you may need additional recommendations from our team on how to best manage them.
If your horse is too thin, make sure that they are getting enough of a high-quality forage source first. Before adding in or increasing a concentrate, check with our equine veterinarians. They may recommend checking a fecal sample for GI parasites and examining your horse’s teeth as these could cause weight loss too. If you do need to increase the amount of concentrate or begin supplementing fat, remember to do so gradually.
Ensuring Your Horse's Health and Well-being
Understanding and catering to your horse's unique digestive needs is essential for their health and happiness. By paying close attention to their diet, dental health, and overall gastrointestinal functioning, you can significantly enhance their quality of life.
If you have any questions or need personalized advice for your equine friend, don't hesitate to reach out to our team of experienced veterinarians at Hoof & Paw Veterinary Services in Purcellville, VA. We're here to help you ensure your horse thrives!