Effects of dietary lipid level on grow th performance，digestive enzyme activity and anti-oxidative capacity after heat stress in juvenile sea urchin Strongylocentrotus intermedius
Abstract: Juvenile sea urchin Strongylocentrotus intermedius were fed diets containing 3％，6％，9％，12％and 15％of lipid for 96 days to investigate the effects of dietary lipid levels on growth performance，digestive enzyme activity and anti-oxidative capacity.Results showed that there was significantly higher or themaximal weight gain rate（WGR）in the sea urchin fed the diet containing 3％lipid than that in the sea urchin fed the diet containing 15％lipid（P＜0.05）.The amylase activity was shown to be significantly lower（P＜0.05）and lower in pepsin in the sea urchin juveniles fed the elevated lipid diets.Lipase activity was increased significantly with the increase in dietary lipid（P＜0.05）.Relatively high dietary lipid（6％-12％）led to improve activity of superoxide dismutase（SOD）and anti-oxidant capacity（AOC）in the thermal stress sea urchin，with the maximal SOD activity in the sea urchin exposed to 2 and 6 hour thermal stress in the 12％dietary lipid group，and significantly higher than that in the 15％dietary lipid group（P＜0.05）.Themaximal catalase（CAT）activity in coelomic fluid was observed in the sea urchin exposed to 15 min and 6 hour thermal stress in the 6％dietary lipid group，significantly higher than that in the 12％and 15％dietary lipid groups，and higher than that in the 15％dietary lipid group（P＜0.05），indicating that6％-12％lipid was of the optimal for improvement of anti-oxidative capacity in response to thermal stress，though 6％lipid was suggested to be optimal for the growth of sea urchin.
2016, Vol. 31 
