Effects of three kinds of carbohydrate sources onnutrient metabolism in Litopenaeus vannamei postlarvae during starvation and compensatory growth

The present study investigated the effect of two states (hunger and refeeding) on the growth performance, body composition and related metabolism of Litopenaeus vannamei. There were 5 treatments in the experiment, which were starvation group (S0), control group (C), experimental group named S1, S2 and S3 (sugar sources: glucose, sucrose, cornstarch, respectively), while the juvenile L. vannamei (1.84±0.23) g continue to feed for 12 days after 12 days of starvation. The results showed that starvation affected body composition of juvenile L. vannamei postlarvae and related enzymes lipase (LPS), phosphofructokinase (PFK), hexokinase (HK), glutamine synthetase (GS) significantly; shrimp liver and muscle glycogen were repeated movements, after 8 d starvation glycogen dropped to the lowest value, muscle glycogen decreased significantly after a brief rebound. The weight gain in S3 group was the highest after refeeding 4 days, the experimental groups were lower than the C group significantly and it was not significant among the experimental groups. The liver glycogen, muscle glycogen content in S1 was significantly lower, The activity of LPS and HK increased greatly during the early days of refeeding, and there was no significant difference in the content of LPS and PFK between the experimental groups. After refeeding 12 days, the activity of LPS and HK in S3 was significantly higher the other experimental groups; there was no significant different between GS and PFK content in experimental groups. The study showed that the glycogen and fat were first used for energy supply during the starvation of L. vannamei, and the refeeding was partly compensated for growth, and the effect of corn starch sugar source feed was the best.