盐度和温度对大菱鲆幼鱼抗氧化酶活性的影响

Effects of temperature and salinity on the activities of antioxidant enzymes of juvenile turbot Scophthalmus maximus

采用两因素交叉分组的方法,研究了温度和盐度对大菱鲆Scophthalmus maximus幼鱼行为活动、摄食、存活情况以及体表黏液、血液、鳃、肝脏中抗氧化酶活力的影响。结果表明:水温(17、20、23、25、28℃)和盐度(5、10、20、30、40)对大菱鲆幼鱼摄食、死亡率有显著影响(P<0.05),在水温为17、20℃与盐度为20、30的组合条件下,大菱鲆幼鱼的摄食积极性以及存活率较高,显著高于其他组(P<0.05);温度和盐度对大菱鲆幼鱼SOD、CAT与GP-X活力有显著影响(P<0.05);当温度一定,盐度变化的条件下,肝脏、鳃、血清和黏液中的各种酶活力在正常海水盐度(30)时活力较低,并随盐度由30起降低或升高而均出现升高的趋势;当盐度一定,温度变化的条件下,随着水温的升高,各组织中的酶活力变化规律不显著;通过分析温度与盐度交互作用对各组织不同酶活的变化以及生命表征现象,得出了最适生存阈值,即大菱鲆幼鱼的适宜生活水温为17～20℃,适宜生活盐度为20～30。

Two-factor-intersecting experiment was designed to evaluate the effects of temperature（17,20,23,25,and 28 ℃） and salinity（5,10,20,30,and 40） on mortality and antioxidant enzymatic activities in the mucus,blood,gills and liver of juvenile turbot Scophthalmus maximus.The results showed that the fish had a good ingestion at 17 ℃ and 20 ℃,and salinity of 20 and 30.The activities of SOD,CAT,and GP-X in the mucus,blood,gills and liver were affected by both temperature and salinity significantly（P0.05）.Within a certain temperature,lower activities of SOD,CAT,and GP-X were observed at a salinity of 30,increasing as the salinity increased or decreased from the normal salinity of 30.Within certain salinity,there were no regular changes in the enzymatic activities as the temperature increased.According to the changes in enzymatic activity and exosyndrome of life and in the two-factor experiment,it is conclude that 17-20 ℃ is of the optimal temperature,and 20-30 is the salinity for juvenile turbot.