Similar pattern of increased activity was also observed in case of liver i.e., highest in O. niloticus (270.47%) and minimum activity of 117.68% in H. fossilis was observed, while the intestine showed maximum enzyme activity in A. testudineus (164.58%) and minimum in H. fossilis (114.04%) respectively. The result showed that highest protease activity was observed in liver of O. niloticus (270.47%) and lowest in stomach of H. fossilis (114.04%) in respect to allthe