Protease Activites in Digestive Organs of Walleye

Protease activity in the digestive organs of Wallege from the culture pond were measured.The results show that the optimun pH values for the protease in stomach,hepatopancreas,pyloric caeca and intestine were 3 0,7 0,8 0 and 8 0 respectively.The sequeme of protease activity, from high to low, was stomachpyloric caecaintestinehepatopancreas.The digestive enzgme activity in the intestine was different from different parts.The protease activity was decreasing gradually in intestine from proximal to distal.There were significant differences among them( P 0 05).With the growing of Wallege,the protease activity increased in digestive organs.In the fingerling period(body weight≤4?g),the protease activties were low and food was mainly digested in stomach.When body weight was over 13 4?g,the protease activity increased in every digestive organ.When body weight reached 63～102?g,the function of digestive organs approached mature,there is a dicreasing tendency afterwards.