Abstract: Juvenile sea cucumber Apostichopus japonicus Selenka with initial body weight of 5.36-5.57 g were stocked into 40 liter plastic tanks at a rate of 15 individuals per tank and fed the diets containing selenoyeast,sodium selenite,selenomethionine,or selenium powder at a rate of 0.4×10-6selenium(without addition of selenium as control)with triplication at water temperature of 13.0-20.0℃,a salinity of 31-32,and pH 7.5 for 60 days.The results showed that the sea cucumber fed the diets supplemented with selenium had significantly higher special growth rate than the animals fed the diets without supplementation of selenium did(P＜0.05),the maximal body weight gain being observed in the sea cucumber fed the diets containing selenomethionine.There were no significant differences in the activities of superoxide dismutase(SOD),and catalase(CAT)in the coelomic fluid of the sea cucumber between the treatment and the control groups.However,it was found that the acid phosphatase(ACP) in the coelomic fluid was significantly higher in the selenoyseast group than that in the control group,indicating that the selenium supplementation significantly improved the growth performance in the sea cucumber.Improvement of sea cucumber growth by supplementation of selenium was found to be attributed to the increase in digestibility of dietary protein;high survival of sea cucumber by supplementation of selenium was shown to be dependent on the high activities of SOD,CAT,and ACP in the coelomic fluid.There was better improvement of digestibility and retention of dietary protein,leading to higher special growth rate,by organic selenium than by inorganic selenium.
2011, Vol. 26 
