Corn gluten meal is one of the main by-products of corn starch plants. The protein content varies greatly depending on the processing technology, generally 35% ~ 60%. Poor amino acid composition, high methionine content, equivalent to fish meal with the same protein content; lysine and tryptophan are seriously insufficient, less than 1/4 of the fish meal with the same protein content. The level of metabolizable energy is close to that of corn, and the crude fiber content is low and easy to digest. Less mineral content, low calcium and phosphorus content. The carotene content is high and the B group vitamin content is low. When using this kind of feed, it should be used with feeds with high lysine content or add appropriate lysine to maintain the balance of amino acids.