Effects of dietary carbohydrate on the growth and the levels of the hepatopancreatic glycogen and serum glucose of prawn.

This study deals with the effects of dietary carbohydrates on the body weight gain, survival, protein efficiency ratio, and the hepatopancreatic glycogen and serum glucose levels of the prawn, Penaeus japonicus. The highest weight gain was attained in the diet containing 19.5% maltose as a carbohydrate source. The growth of prawn was poor in the diets containing high levels of the monosaccharides glucose and galactose, as compared with that of prawns which received the disaccharides sucrose and maltose, and the polysaccharides soluble starch, potato starch, dextrin, and glycogen. Feeding with diets containing glucose or galactose for 30 days resulted in high hepatopancreatic glycogen concentrations. Also, the serum glucose level of the prawn increased quickly after oral administration of glucose and remained at high levels for 24 h, whereas after the administration of disacchazides and polysaccharides, it increased to a maximum level after 3 h and then decreased to the pre-test level.