How Much to Feed a Horse Based on Weight

A horse's digestive tract is designed to accommodate a certain amount of feed based on his weight. Though this provides a foundation for determining the amount of feed to give a horse, the final determination should be tailored to more than just body weight. The horse's daily activity and natural body score should also play a factor.
  1. Feed

    • Horses naturally can consume massive quantities of any available vegetation--up to 1.5 to 2.5 percent of their body weight daily. For the average 1,000-pound horse this equals 15 to 25 pounds of hay a day. Hay has vastly different nutritional qualities however, meaning 15 pounds of two different types of hay will have different nutritional and caloric compositions. A horse will keep his weight up eating less of a nutrient-rich hay like alfalfa, that is very high in both calories and protein, as opposed to a nutrient-poor filler like Bermuda grass.

      Horses, like people, tend to be naturally thin or naturally fat. Some horses, regardless of how much they eat, tend to stay lean. These horses are hard keepers and can be picked out of a shed row of horses by the piles of hay constantly in front of them that they don't seem to care about eating. Other horses can eat the smallest flake of hay twice a day, equaling 1 percent of their body weight, and they blow up like a balloon. Your horse's body condition is the best indicator of if he is eating too much or too little.

    Extra Calories

    • Feeding a horse based on his weight is a guideline, but when the horse is in consistent heavy work, like during horse show season, he may need more feed or to be grained. Just like human athletes, horses that work hard every day, in disciplines like dressage, show jumping or western reining, require more energy to be able to perform and keep their body weight up. Hay has a lower caloric density then grains, like corn or oats. It is often necessary to supplement their diet with grain to provide him with enough calories.

      For horses that work for a living, base their diet of hay off their body weight and then modify the diet with more hay, richer hay or grain as needed. Keep track of their body score and energy level during work. A horse that is worked regularly but grows tired quickly may need grain added to his diet. A horse's body condition should be round but not overly fat; you should be able to feel, but not see, his ribs. If you can start to see bones, he may need some more feed. Conversely, if you have to go digging to feel a rib, it is time to cut back.