Horses That Graze on Pasture All Day Eat More Slowly Logo

Feeding Tips from Dr. Juliet Getty

Horses that graze all day on Pasture eat more slowly

If you let your horse out to graze on pasture for only a few hours each day, and provide hay the rest of the time, you’ve likely noticed how he approaches the grass like a vacuum cleaner, barely lifting his head the entire time he is outside. On the other hand, horses who graze on pasture 24/7 are more relaxed, eating less grass at a slower pace, taking time to rest and interact with buddies.

Researchers at North Carolina State University were interested in just how much pasture horses consume at varying combinations of pasture and hay availability. What they found confirms what we have all witnessed. At varying levels of pasture turnout, an 1100 lb (500 kg) horse will consume the following amounts of grass dry matter (all horses were given free choice hay when removed from pasture):

  • 24 hours/day: 0.77 lb per hour (0.35 kg/hr)
  • 9 hours/day: 1.32 lb/hr (0.6 kg/hr)
  • 6 hours/day: 1.65 lb/hr (0.75 kg/hr)
  • 3 hours/day: 2.2 lb/hr (1.0 kg/hr)

The less time you allow for pasture grazing, the more excited your horse will be at the opportunity to have fresh grass and will eat nearly three times faster than if he had access to pasture 24/7.

Note: To convert lb/hr to kg/hr, divide by 2.2


Which should be fed first – hay or grain?  If you’re feeding correctly, this issue is truly a moot point because the horse should have access to forage (hay and/or pasture) 24/7 with no gaps. Therefore, when fed concentrates, the horse’s digestive tract should already have hay flowing through it.

If fed starchy cereal grains (oats, corn, barley, etc.) on an empty stomach, the horse will produce even more acid (potentially leading to ulcers) and it will be leave the stomach quickly. When this happens, there is a risk that it will not be fully digested in the small intestine (especially if large amounts are fed), and end up in the hindgut where starch can be fermented by the bacterial population. This can lead to endotoxin-related laminitis.

If hay is present in the stomach first, it creates a physical barrier for the grain to move out of the stomach as quickly. Starch does not get digested in the stomach so the grain is simply mixed and churned into a semi-liquid mass, which enters the small intestine where it can be digested down to glucose. If there is hay present, fiber mixes with the starch and the whole mass enters the small intestine. Fiber is not digested until it reaches the hind gut, but its presence slows down the digestion of starch, and obstructs the absorption of glucose into the bloodstream, leading to a less dramatic rise in insulin.

One thing to note – there is more water involved when hay is present (from increased drinking and saliva production). This is a good thing since digestion within the small intestine cannot take place without water.


“For an adult horse with moderate activity, feed .75 to 1.0 lbs per 100 lbs of body weight.” These are the feeding instructions for a popular commercially fortified feed. If your horse weighs 1100 lbs (500 kg), you’ll need to feed 8.25 to 11 lbs of feed per day. For enough calories? Enough protein? Enough vitamins and minerals?  Yes, to all of the above and more. That’s a lot of feed!  That could amount to three to five two-quart scoops (depending on the weight of the feed) per day. And you’ll need to divide it into multiple feedings since meal size should never exceed 4 lbs (your horse’s stomach is small compared to the rest of his digestive tract).

Chances are excellent that you don’t feed anything close to the suggested amount.  Does it matter? Yes. Most of what you pay for when you buy a fortified feed, are the fortifications. You pay for the vitamins, the minerals, and any special ingredients such as flaxseed and soybean meals to provide omega 3s and protein. The only way your horse will benefit from these nutrients is to feed according to directions. Modify them and you’ll need to “supplement the supplement.”  For example, this feed provides 100 IUs of vitamin E per lb. If you fed half of the recommended amount, say 5 lbs, your horse would only receive 500 IUs per day. That’s the bare minimum, according to the National Research Council, for a 500 kg horse. Most equine nutritionists agree, however, that this horse at maintenance would do better at amounts closer to 1,000 IUs per day. Furthermore, as activity increases, so does the vitamin E requirement. Therefore, supplementation would be appropriate.

Other nutrients such as omega 3 fatty acids, vitamins A and D, minerals such as copper and zinc, and a host of feedstuffs provided to offer enough fat and protein, may need to be supplemented when less than recommended amounts are fed. As you can imagine, it becomes very tricky to figure out just how much to supplement. You could simply give half the supplement dosage if you are feeding half the fortified feed dosage. But to do this accurately, you should figure out how much your horse would have gotten if fed the recommended amounts, and then calculate how much supplement to feed to make up the difference. If you’re not comfortable with crunching numbers, your best source of information would be a qualified equine nutritionist.

Bottom line… pay attention to labels, weigh your feed using a scale, not a scoop, and keep your calculator handy when making adjustments that supplement the supplement.


Regardless of the weather, horses require a daily supply of salt. In cold seasons, salt helps promote enough water consumption to prevent dehydration. In warm seasons, salt replaces what is lost from perspiration. A full-sized horse requires at least one ounce (two level tablespoons or 30 ml) of salt each day for maintenance, this much provides 12 grams of sodium. Heat, humidity, and exercise increase the horse’s need.

There are several ways to accomplish this. The best ways include offering free-choice granulated salt, or adding salt to your horse’s meal (for palatability, limit the amount to no more than 1 tablespoon per meal). A salt block should be available should your horse want more. A plain, white salt block is preferable, but many horses do not lick it adequately since it can be irritating to the tongue. Mineralized blocks often go untouched due to their bitter taste; however a natural sea salt block is often preferred.

Calculate the amount of sodium your horse is getting from any commercial feeds or supplements and add salt accordingly. Always have fresh water nearby.

Hydration And Horses Logo

I know what happens if horses don’t drink enough. Too often in the past, I’ve seen horses that don’t drink much water have bouts with colic and mild digestive upset. No matter what you do with your horses, it’s important to make sure they have regular and constant access to fresh clean water—especially those that are finicky, like my horse Dually.

Necessity of Water
No matter what you do with your horses, water must be a first priority. When I led out big pack trips through the Rocky Mountains, we had to make sure to take trails that bordered streams and that the horses were allowed to drink each time we crossed a stream. The experienced and wise trail horse drinks at every opportunity because he doesn’t know when the next opportunity will come.

When we take our horses on the road, I make sure they have water breaks if they are in the trailer more than a few hours; and we carry water from home, just to make sure it is familiar and tempting.

When horses are at home in the pasture, I make sure that everyone knows what gates should stay open so that horses can get to the water tanks. Horses need regular access to water.

But even if you offer water consistently, what can you do to make sure your horses keep drinking—especially when you have a horse that doesn’t drink much? Salt is a necessity in a horse’s diet. You know that if you eat a bag of salty potato chips, you’ll crave a drink. I wouldn’t eat chips unless I had my water bottle in my hand. The same is true with horses—giving salt can encourage horses to drink more. Salt plays a vital role in hydration (water retention), muscle contraction and contains nutrients and minerals that are vital to digestive health.

When you drink more, your kidneys can keep the appropriate amount of electrolytes in the bloodstream and also impacts blood pressure. The same is true for horses. Salt also plays a role in digestion by helping break down food and by increasing hydrochloric acid, which lines the stomach walls and aids in the digestion of food.

Salt in Nature
Salt deposits are found in nature and wild horses would find them in their foraging areas, if left to roam. With domestication and confinement, we have to provide salt, since the horse cannot go looking for it. Most horses will voluntarily consume salt in the quantities they need, but there are always a few “high maintenance” horses whose salt consumption must be monitored.

Here are some tips to help make sure your horse keeps licking salt and drinking water no matter where you are:

For the traveling horse: Before we leave on a trip with our horses, we package their daily grain ration and supplements in a baggie—one for each day (or two baggies if they get grain twice a day). I always add a little granulated salt each day (Redmond’s Daily Red) just to make sure the horse is drinking well, and so we don’t have to carry around a salt lick.

For the high-maintenance horse: I know some horses that just won’t lick a rock and oddly enough, these seem to be the same horses that don’t drink enough. For these horses, I like to top dress their feed with granulated salt every day. Since horses are generally very good about monitoring their own salt intake, I don’t want to force too much salt on them. Start with about a half an ounce and monitor their water intake and urine output (how much shavings are you going through?). If they still need to drink more, add a little more to their ration.

For the Type A horses: Some horses feel stress more than others and some horses lead a very physically and mentally stressful life. Research has shown that many of these horses are prone to ulcers, which may manifest in poor appetites, decreased energy, lack-luster attitude and colic-like symptoms. Horses prone to ulcers may be reluctant to consume salt, but they still need some in their diet. My number one horse, Dually, falls into this category. For him, I feed Redmond Daily Gold, a clay-based salt and mineral supplement that helps neutralize stomach-acid build-up and improves appetite and digestion. As a matter of fact, I take it myself daily (in a capsule made by Redmond for humans) for indigestion, so I have a sense of how much it helps me and what it may be doing for Dually.

For the finicky horse: Some horses won’t lick a rock of salt on the ground, but if you hang it up on the fence, they’ll enjoy licking it a lot more. Hanging up on the fence, especially if it is near his water bucket, will make it an enticing toy and keep it clean. Some horses won’t lick on a rock on the ground if it is dusty and dirty.

No matter what salt you choose, make sure your horse has access to salt daily—and of course, make sure water is clean and fresh.

Enjoy the ride,

Julie Goodnight