Fish (scientific name: Piscium), is the body was bony scales, gill breathing, through the tail and trunk of the swing and fins of the coordinated role of swimming and feeding with the upper and lower jaws of the variable temperature of aquatic vertebrates collectively, belongs to the phylum of chordata in the vertebrate subphylum, is the oldest vertebrates. Fish is rich in animal protein and phosphorus, etc., on the development of human physical and mental strength has a significant role.