The Compensatory Growth in the Sea Urchin Hemicentrotus pulcherrimus Following Starvation and Refeeding

The recovery growth experiment was conducted with sea urchin(Hemicentrotus pulcherrimus) starved for different periods.The groups arranged as C,T1,T2 and T3 were deprived of food for 0(control),1,2 and 4 weeks,respectively,and then refed at ad libitum ration levels for the remaining experiment time.The experiment lasted for 8 weeks.At the end of starvation,the body weights of each starved groups(T1,T2 and T3) were lower than those of group C.The gonad indexes of T1 and T2 were lower than those of group C,and the gonad indexes of T3 were significantly lower than those of group C.The water contents of the sea urchins increased when they were under starvation for more than 1 week.The protein contents decreased and then increased slowly.The lipid contents did not change after 2 weeks starvation and decreased sharply after 4 weeks starvation.After 1 week starvation it was observed that the carbohydrates did not change,and then decreased slowly.After the completion of refeeding,the chemical compositions had recovered to the level of the control group.After the experiment the body weights and gonad indexes of the sea urchins were close to those of the control group.The results showed that there was a complete compensatory growth in Hemicentrotus pulcherrimus by means of increasing feed intake(FR) and absorption efficiency(AE).