Rice bran is a by-product of the milling of rice. It consists mostly of the bran layer and germ of the rice with some fragments of hull and broken rice. The calcium level in rice bran will vary with the amount of added calcium carbonate. When the amount of added calcium carbonate exceeds 3 percent (total calcium exceeds 1.2 percent), then the percentage of calcium carbonate must be stated in the product name. Rice bran is similar to oats in crude protein, fat, fiber and energy. It is a palatable feedstuff, which can be included in the grain mixture at a rate of up to 25 percent or fed at a rate of up to 8 pounds (3.6 kg) per cow per day.