高温对虾夷扇贝体腔液免疫酶活力的影响

Effects of high temperature on the immuno-enzymetic activity in coelomic fluid of Mizuhopecten yessoensis

在实验室内检测了虾夷扇贝对高温突变的耐受能力及在不同高温水平下的存活与相关免疫酶活力。实验分两个阶段:实验Ⅰ,15℃暂养的虾夷扇贝分别被驯化到20、22、24及26℃,检测虾夷扇贝的存活及相关免疫指标。结果表明,15～22℃处理组虾夷扇贝存活率均大于85.21%,且组间无显著差异(P>0.05),26℃处理组存活率最低,为26.33%。随温度升高,虾夷扇贝体腔液中T-AOC和MDA含量变化显著(P<0.05),SOD活力差异不显著(P>0.05),CAT活力随温度升高呈先下降后上升趋势。实验Ⅱ,15℃暂养的虾夷扇贝分别被放到20、22、24及26℃,并在1、2、4、8、12、24、48和96 h时检测其存活和相关免疫指标。结果显示,经96 h胁迫,15～24℃处理组间虾夷扇贝的存活率无显著差异(P>0.05),且均大于82.29%,但26℃处理组虾夷扇贝在经12 h胁迫后,其存活率降为0。2龄虾夷扇贝在8、12、24、48和96 h半致死温度(LT50)分别为27.52、24.41、24.37、24.24和23.81℃。

In this study,we tested the high temperature mutation tolerance,survival and immune enzyme activity under different high temperature levels of Mizuhopecten yessoensis.There are two stages in our laboratory experiments.Firstly,we transferred M.yessoensis from the rearing temperature（15 ℃,control temperature）to 20,22,24and 26 ℃,and then we tested the survival and related immune indicators of M.yessoensis.The survival of M.yessoensis was not affected by temperature from 15 ℃ to 22 ℃ with survival rate exceeding 85.21%,and there is no significant difference in different groups（P0.05）,M.yessoensis exposed to 26 ℃ were significantly affected by temperature,with a survival rate of 26.33%.With the temperature rising,the T-AOC and MDA content in the body cavity fluid of M.yessoensis significantly changed（P0.05）.The CAT vitality would rise after the initial drop with the rise of temperature.There were no significant differences among different groups,SOD vitality（P0.05）.Secondly,we abruptly transferred scallops from the rearing temperature（15 ℃,control temperature）to 20,22,24 and 26 ℃ levels,and examined related immune indexes at 1,2,4,8,12,24,48 and 96 h.The results showed that,the survival of M.yessoensis was not affected by temperature from 15 ℃ to 24 ℃ during the 96-h exposure periods with survival rate exceeding 82.29%.M.yessoensis exposed to 26 ℃ were significantly affected by temperature,with a survival rate of 0% after 12 h.The 8,12,24,48 and 96 h lethal temperature for 50%（LT50）were 27.52,24.41,24.37,24.24 and 23.81 ℃ respectively.