How to Calculate How Much Hay to Feed Your Horse

Horses require a diet of grass or hay. If your horse is grazing on grass, monitor its condition closely to ensure it is not overeating or undereating. Horses can overeat grass, especially if the pasture is lush, but it is also easy to let a horse get too fat from eating hay. And, sometimes too little hay can mean a horse will lose weight. So, what is the right amount of hay for your horse?

Just how much your horse will need will depend on its weight. According to the Ontario Ministry of Agriculture, a full-grown horse should eat about 12 to 15 pounds (5.4 to 6.8 kilograms) of hay a day. That is 1.5% to 3% of its body weight if it weighs about 1,000 pounds (450 kilograms). This is a very rough average, and horses may require more or less, depending on their metabolism, workload, what else they may be eating, and the time of year. Ponies will require considerably less, while large draft breeds can eat 30 pounds (13.6 kilograms) a day or more.

How to Feed Hay

Providing small, frequent portions of hay mimics natural grazing instincts and is healthiest for your horse's mental and physical well-being. So try not to feed your horse a full day’s worth in one meal. It will probably gorge on the best parts of the meal, leaving the least tasty, then trample what's left into the ground. For the healthiest digestive system and the happiest horse, it is best to have hay available at all times. Most horses are self-regulating, but many are not. Some horses will need their hay diet restricted to prevent obesity. Such horses should be fed small, more frequent portions. For many horses, hay is all they need, and they won’t need concentrates such as oats or sweet feed, or particularly rich hay that contains legumes like clover and alfalfa.

Small Square Bales

The next question, however, is: How much of a small square bale is that? What you will have to do is weigh an average bale of hay. It should weigh approximately 60 pounds or 23 kilograms. The exact weight will depend on how dry the hay is, how long the bales are, and how tightly packed the hay has been baled. Next, count how many flakes are in the bale. The flakes are the easily divided sections that are formed when a square bale is picked up by the baler. There are usually about 12. Now divide the weight of the bale by the number of flakes in it. You'll now be able to calculate the approximate number of flakes you should feed your horse daily. So if a flake weighs about four pounds, you’ll need to feed your 1,000-pound horse five flakes every day. Remember to feed in as many small portions as possible.

Ponies and Draft Breeds

Because ponies have a slower metabolism than horses, they’ll need a lower percentage of their body weight of hay, unless they are working very hard, which few ponies do anymore. Small ponies may only need a couple of flakes every day to keep them in good condition. But, conversely, some draft horses, especially ones that work hard, will need rather more than the normal ratio of hay. This is why it is so important to regularly monitor your horse’s condition, and make adjustments depending on the season, how hot or cold it is, how hard they are working, their age, the richness of the hay, and the horse’s overall health.