The crude protein content of peanut bran (peanut cake) is generally 37-44%, of which 63% is water-insoluble globulin and only 7% is water-soluble albumin. The composition of amino acids is unbalanced, and the contents of lysine and methionine are low. The content of arginine is the highest among all plant feeds, and the ratio of lysine to arginine is above 100: 300. It is suitable for livestock to feed rapeseed cake with low arginine content. Peanut bran (peanut cake) is susceptible to Aspergillus flavus and cannot be used to feed fish? But peanut bran is widely used in practical production.