Effect Of Starvation And Refeeding On The Activity Of Digestive Enzymes, Feeding And Growth, Biochemical Composition Of Erythroculter Ilishaeformis Juvenile

Erythroculter ilishaeformis, because of its great economic value and better reproductive performance, is one of important breeding species. Now, many researches focus on the biological characterization and breeding technology, but studies on its starvation physiology have not been conducted. In this experiment, the effects of starvation and subsequent refeeding on the activity of digestive enzymes (including protease, lipase and amylase), feeding and growth, the biochemical composition were investigated The tested fish were divided into 5 experimental groups (A, B, C, D and E), each group having 3 replicates. The fish were starved of food for 0(control group A), 4days(group B), 8days(group C), 12days(group D) and 16days(group E), then the fish of each group were refed (fed to satiation) for 16 days. Test the activity of digestive enzymes, body weight and the biochemical composition of the fish through measuring the samples of each group. The experimental results are shown as follows:1. With the prolonging of starvation, the activity of digestive enzymes in the foregut, the hindgut and the liver all fell. At the beginning of starvation, the activity of digestive enzymes fell markedly. At the 4th day of starvation it stepped down sharply except the activity of lipase in the foregut. But when the fish were starved further, the activity of enzymes didn't change significantly. Upon refeeding, the activity of digestive enzymes in starved fish rose quickly, at the 4th day it reached to peak, and then fell down to the level of control fish.2. Before starvation the body weight of fish was similar, but after starvation, the body weight of the fish of group E was significantly lower than that of other fish (P<0.05), and that of the fish of group D was also lower than that of the fish of group B. The rate of loss weight also increased with the prolonging of starvation.Upon refeeding, the conversion efficiency of starved fish was similar with fed fish, but the feeding rate of starved fish was significantly higher than the fed fish (P<0.05), and the specific growth rate of the starved fish except group E was also significantly higher than the fed fish (P<0.05). At the end of experiment ended, the body weight of the fish of group B and group C was similar to that of fed fish, and that of the fish of group D and...