Effects of deltamethrin on main immune parameters of Chinese mitten crab，Eriochier sinensis

In this research，the effects of deltamethrin on immune parameters were revealed by dectecting the changes of total hemocytes count（ THC），phagocytic activity，phenoloxidase（PO） activity，acid phosphatase （ACP） activity and alkaline phosphatase（AKP） activity in hemolymph of Chinese mitten crab under different concentrations of deltamethrin（0，0.19，0.30，0.41，0.52 μg/L） exposure. The results showed that deltamethrin had evident effects on immune parameters of Chinese mitten crab，THC increased after 6 h and 12 h exposure to low concentrations of deltamethrin including 0.19 μg/L and 0.30 μg/L，and then decreased to normal level at 96 h. On the contrary，high concentration（ 0.41μg/L and 0.52μg/L） exposure declined the THC after 24 h，which was significantly lower than that of control group at 96 h. The phagocytic activity decreased under each concentration and the higher concentration made a higher inhibition of phagocytic activity. After exposure to 0.52μg/L deltamethrin，PO activity increased significantly at 6 h and then decreased gradually till 96 h，which had no significant difference among each group. However，both ACP and AKP activity decreased at 6 h exposure to 0.52μg/L deltamethrin and was significantly lower than those of control at each time point.