Study on immune activity of sea cucumber(Apostichopus japonicus) with different weight

In order to provide basis knowledge on immune system of sea cucumber(Apostichopus japonicus), the immune activity in sea cucumber with different body weight were studied. Three groups of sea cucumbers(50 g, 100 g, and 150 g) were selected in the experiment(10 individuals each). The total coelomocytes numbers, the ratio of various types of coelomocytes and some immune enzyme activities were determined. The results showed that the body weight had a significant effect on total coelomocytes amount, the ratio of various types of coelomocytes, POD and SOD activity, while the PO activity in coelomic fluid of sea cucumber was extremely low. The total coelomocytes amount and SOD activity in 150 g group of sea cucumber were significantly higher than the other two groups, but the POD activity was significantly lower than the other two groups(P0.05). The ratio of various types of coelomocytes in 150 g group had significant difference compared to other groups(P0.017). In a word, the body weight had significant impacts on immune activity of sea cucumber. The immune components of sea cucumber changed in the process of development and the immune defense ability might vary in different stages.