THE ROLE OF FOOD OBJECTS AND ENTERAL MICROBIOTA PROTEASES IN NUTRITIVE AND TEMPERATURE ADAPTATIONS OF THE DIGESTIVE SYSTEM IN FISH
The review presents data on the activity and some temperature characteristics of proteases in the potential food objects of fishes and some enteral microbiota representatives that provide induced autolysis and symbiotic digestion. It is shown that during the active feeding period the total protease activity in the prey tissues exceeds the total protease activity in the fish gastric mucosa by 5-10 times. At low temperature, the relative activity of the prey tissue lysosomal hydrolases (20-35 %) and the enteral microbiota enzymes (up to 45 %) may exceed that of proteases synthesized by the hepatopancreas and functioning in the consumers' intestinal mucosa (less than 10 % maximal activity). The data presented indicate the important role of proteases of food objects and enteral microbiota in nutritive adaptations of the fish digestive system.