This myth is often a result of people feeding on a volume basis and not by weight of the grain. When horse owners are asked how much grain they feed their horse, they answer by saying they feed so many quarts, scoops, coffee cans, etc. One quart of corn weighs approximately 1.7 pounds. One quart of oats weighs approximately 1.0 pound. If you are feeding 4 quarts of oats per feeding and gradually change over to 4 quarts of corn, the total intake of the horse per feeding changes from 4 pounds to 6.8 pounds. Not only is the horse receiving more energy from more total pounds consumed, but corn is higher in energy per pound than oats. Corn contains 1.6 megacalories of digestible energy per pound, whereas oats contain 1.36 megacalories of digestible energy per pound. The horse in the above example goes from consuming 10.9 megacalories per day (8 pounds x 1.36 Mcal D.E./lb.) to 21.8 megacalories per day (13.6 pounds x 1.6 Mcal D.E./lb). Therefore, many horse owners think that feeding corn to their horses makes them "hot," with "hot" meaning that the horse has more energy and may be a little energetic and unmanageable. Similar to feeding candy to a young child, the extra energy can make them hyperactive. Feeding corn does not make them hot in terms of body heat, but will in terms of increased activity. In fact, feeding oats to provide the same amount of digestible energy per day will generate more body heat because oats have a higher fiber content than corn. Fiber digestion generates more body heat. Therefore oats, not corn, will actually produce more body heat.