Your Guide to Natural Horse Grain

Natural horse grain nutrition means providing your horse with whole grains instead of heavily processed feeds. Learn the benefits of feeding a natural horse grain diet, the different types of grains, how much to feed, and how to find them. Horse nutrition is an art and a science and there are many factors to consider when deciding what is best for your horse. Keep in mind that is is best to muscle test all diet ingredients you want to feed your horse to make sure it is ideal for them. To learn more about muscle testing, click here.

Why feed a natural grain diet?

  • Feeds that have been processed or heated destroy food enzymes that help horses digest their food. This makes your horse’s body work harder since they will have to produce additional enzymes to digest the feed.
  • Processed feeds will mold or spoil more quickly than a natural horse grain because they lack the protective coating that unprocessed grains have. When grain has been processed, oxygen effects the contents and may turn the grain rancid. Shelf life can be as short as one month in warm and humid weather. When stored under the right conditions, a natural horse grain can maintain their nutrition for years.
  • It is extremely difficult, if not possible, to tell the quality of grains that have been processed or cooked. With whole grains, you can check the color, size, and cleanliness with your own eyes.
  • Many commercial mixed feeds are not always consistent and the ingredients may change over time as manufacturers change their formulas. This can be hard on horses that have health problems, especially those prone to colic.
  • While processed feeds can contain vitamins, minerals, and more nutrients than whole grains, they can contain ingredients that are not really necessary or the opposite – they can have levels that are considered toxic to your horse, especially if your horse is also receiving a supplement. Have your hay analyzed to find out what your horse really needs in a grain when it comes to protein, vitamins, and minerals.
  • In addition to a natural horse grain diet being healthier for your horse, it’s also easier on your wallet since whole grains cost substantially less than commercial mixed feeds.

Is a natural horse grain diet right for your horse?


  • Oats are considered to be the top choice for horses because they are very tasty and are the most nutrient balanced grain.
  • Oats are thought to aid the milk production of lactating mares and improve the sex drive in stallions.
  • Oats have about 47-53% starch, which is less than other whole grains. Oat starch is more digestible than the starch in corn or barley and less likely to cause problems like founder or colic, so oats are considered the safest grain. Oats do increase blood sugar about 1 1/2-3 hours after being fed, so horses with Cushings disease or gastric ulcers should not be fed this grain.
  • Whole oats, also called hulled or covered, have about 11-13% protein and 5% fat. If you have a growing horse, breeding horse, or horse doing moderate to heavy work, you will probably want higher protein. Hulless oats are available and contain about 27% more protein and 49% more fat than whole oats. They contain about 5% fiber as compared to about 10.5-12% fiber for whole oats, but a Cornell study showed that 40% of the fiber was digestible compared to 30% of the whole oats. (Your main source of fiber should be forage, though.) Hulless oats offer more than hulled oats when it comes to amino acids – 50% more methionine and 60% more lysine. Because hulless oats contain more digestible energy than whole oats, you will feed 1/4 less. Hulless oats are a natural horse grain since the oat itself grows with an envelope but not a hull – it is only to protect from temperature change. When it is ready to be harvested, the envelope falls down.
  • While oats are low in vitamins D, E, K, and several B vitamins, horses should get plenty of vitamin D from the sun OR from hay. Too much vitamin D can actually be toxic and cause serious health problems and even death. Horses manufacture vitamins B and K in their hindgut. A vitamin K deficiency has never been seen in a horse. Research has shown that oats contain high levels of other antioxidants that act to fortify the vitamin E. Oats are low in beta carotene but this is found in fresh forage so it probably is not necessary if pasture is provided.
  • When purchasing oats, it’s best to buy USDA grade 1, which are also referred to as racehorse, jockey, Heavy Number One, or Canadian oats. Many of the top quality oats are imported from Canada. Oats should be triple cleaned so that empty hulls, dirt, dust, and small stones are removed. Oats should be creamy or golden color. Different colors in a bag may indicate more than one lot has been mixed together, which compromises the quality. Oats should also be uniform in size. Triple cleaned oats will cost more than those that have not been screened thoroughly, but are certainly worth it to ensure the quality. Oats are available in crimped/rolled, but keep in mind this increases the cost while only improving the digestibility by 3-5%. If you are concerned about feeding whole oats to young, old, or sick horses, hulless oats are a good choice for a natural horse grain because they are easier to chew and more digestible since there is no hull.


  • Corn is popular because of its low cost and high energy value. It has about twice as much energy as the same volume of oats.
  • This natural horse grain is fed alot in the midwest. Corn can help thin horses gain weight and help hard working horses maintain weight.
  • Corn has about 71% starch, 8-10% protein, and 2-2.5% fiber.
  • Because most of the starch from whole corn is not processed in the foregut and ends up in the hindgut, there is concern for colic and founder. Some horse owners prefer to feed processed corn and have it consist of no more than 25% of a grain diet. Others, however, feed all corn or have it make up a significant part of their horse’s diet.
  • Corn should be a robust yellow color. Different colors in a bag may indicate more than one lot has been mixed together, which compromises the quality. There should be whole kernels of uniform size. USDA grade 1 should have no more than 3% damaged kernels in a 56# bag. Whole corn (husks intact) is very resistant to molding but any other way is at more of a risk (corn that is cracked, broken, or has loose husks). Fusarium molds are very toxic to horses and can be fatal. Purchase your corn from a dealer that only carries whole corn that has been tested and certified as free of fusarium molds. Contact the agriculture extension office where the corn was grown to make sure there are not any problems with fusarium in that location.


  • Some horse owners say that barley improves muscle tone, especially along the top line.
  • Barley is a natural horse grain that has about 65-70% starch, 11-13% protein, and 5-6% fiber. It provides more energy than oats but not as much as corn.
  • Because barley in its whole form has hard kernels which can make it difficult for horses to chew, it is mainly fed rolled or crushed. Like corn, most of the starch ends up in the hindgut.
  • It has been fed to horses with great results but is not fed as much because it tends to be more expensive than oats and corn. Horses also tend to find it less palatable than oats and corn.

There are many benefits to feeding a natural horse grain diet, but some horses may become too excited due to the energy. Some horses do better on a low carbohydrate diet. You know your horse better than anyone else, but you can certainly consult your vet or a nutritionist for their recommendation.

How much natural horse grain should you feed your horse?

How much to feed depends on several factors:

  • What grain or grains you are feeding. Remember that grains are not equal, for instance, 2.5kg of oats is about the equivalence of 1.75kg of corn or 2.1kg of barley. You may want to consider a combination of grains like oats and corn (50/50 is a common ratio to feed) or adding beet pulp or bran. Your vet or nutritionist can help you decide what is best for your horse. Know and understand the ingredients you are getting in your horse’s grain. Click here to find an excellent article that describes in detail how to decipher the information on a natural horse grain feed tag or any other horse grain feed tag.
  • What your horse’s age, weight, health, and their level of activity are (breeding, light work, heavy work, etc.) There are many sites that recommend amounts but Click here for a good one.
  • The amount of pasture and/or hay that you are feeding. The roughage horses receive should be a minimum of 1% of their weight. You should balance the amount of protein in your grain with the amount in your hay. Remember that alfalfa hay has more protein than grass hay. It is a good idea to get your hay analyzed. Your county or state agricultural office can test your hay. The National Forage Testing Association can help you locate a lab near you if you are unable to find one. Phone: 402 333-7485; E-mail: NFTA@TCONL.COM; website:
    When you have had your hay analyzed and determined the natural horse grain or grains and the amount you will be feeding, you may find that you need to feed a supplement to make sure your horse is receiving adequate amounts of the necessary vitamins and minerals. For information on vitamins, click here for Your Guide to Natural Horse Vitamins. For information on minerals, click here for Your Guide to Horse Nutrition Minerals.How can you find a natural horse grain dealer?

    If your local feed store does not carry a natural horse grain or those that are of good quality, contact your county agricultural office. If they are unable to help, you can look on the internet for your state’s department of agriculture website. Some sites will have classified ads that feature grains for sale. You can also try contacting your state’s grain and feed association to help you find a natural horse grain dealer.

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