pH突变对拟穴青蟹免疫因子的胁迫影响

Effect of Sudden Changes in pH on the Immune Factors of Scylla paramamosain

以拟穴青蟹为材料,在实验室条件下测定了pH 6.5、pH 7.0、pH 7.5、pH 8.0、pH 8.5各梯度胁迫0h、24h、48h、72h、96h时青蟹的血细胞总数(THC)、血细胞吞噬能力及血清中溶菌酶(LZM)、超氧化物歧化酶(SOD)、碱性磷酸酶(AKP)、酸性磷酸酶(ACP)、过氧化物酶(POD)、酚氧化酶(PO)及溶血素等相关免疫因子的活力变化.结果表明:长时间胁迫使各免疫指标值下降,显示可抑制免疫因子的活性,其中THC、LZM和溶血素活力下降明显.小幅度(pH 7.05、pH 8.02)突变下短时间内各项指标值有所上升,而后下降;大幅度(pH 6.45、pH 8.44)突变各项指标值显著降低.pH胁迫24h后对照组的THC显著高于其他各组;pH 7.05、pH 6.45、pH 8.02组的溶血素活力显著低于对照组;pH 8.44、pH 6.45组的血细胞吞噬作用和ACP活力显著低于对照组.可见THC、溶血素、血细胞吞噬能力、PO和POD可作为pH胁迫对拟穴青蟹抗病力影响的重要参考依据.

Taking the healthy Scylla paramamosain as the test sample,the vitality of immune factors is examined including total haemocyte count（THC）,phagocytic activity,and lysozyme（LZM）,super oxide dismutase（SOD）,alkaline phosphatase（AKP）,acidic phosphatase（ACP）,peroxidase（POD）,phenoloxidase（PO） and hemolysin activities in the serum under pH 6.5,7.0,7.5,8.0,8.5 for 0,4,48,72,96 hours,respectively.The results indicate that long time’s pH stress may reduce each immune response of Scylla paramamosain.It shows that pH mutation can suppress the vitality of immune factors,with THC,LZM,and hemolysin activities being decreased significantly.pH variation of small-scale（pH 7.50 to 7.05 and 7.50 to 8.02） can make the immune indexes increase for a short time followed by decreasing,but pH with significant variation（pH 7.50 to 6.45 and 7.50 to 8.44） can result in remarkable decrease.The immune index of THC in the control group is found to be much higher than that in the experimental groups under 24 hours pH stress.The immune indexes of hemolysin activity in the groups of pH 7.05,6.45,8.02 are much lower than that in the control group.The immune indexes of phagocytic activity and ACP in the groups of pH 8.44,6.45 are much lower than that in the control group.The main immune factors,such as THC,hemolysin,phagocytic activity,PO and POD,can be used as early-warning signals in Scylla paramamosain cultivation.