“In addition, the … of dietary Cu at a level 3.75 ….25 mg/kg diet on trypsin , chymotrypsin, and lipase activities in the hepatopancreas and of Na+, K+-ATPase, alkaline phosphatase, creatine kinase, …-glutamyl transpeptidase activities in three intestine segments produced significantly (P<0.05) better feed efficiency (FE).”