短期温度胁迫对驼背鲈(♀)×鞍带石斑鱼(♂)杂交子代幼鱼抗氧化及消化酶活性的影响

Effects of Short-Term Temperature Stress on Antioxidant and Digestive Enzymes of Hybrid Progeny (Cromileptes altivelis Valenciennes ♀ × Epinephelus lanceolatus ♂)

中文关键词: 驼背鲈×鞍带石斑鱼杂交子代  温度胁迫  抗氧化性  消化酶

英文关键词: Hybrid progeny (Cromileptes altivelis Valenciennes ♀ × Epinephelus lanceolatus ♂)  Temperature stress  Antioxidation  Digestive enzymes

中文摘要:

      本研究设置温度突变组(21℃、24℃、28℃、32℃和35℃)和温度渐变组(每天升温1℃)，探讨不同程度的温度变化胁迫对驼背鲈(Cromileptes altivelis Valenciennes ♀)与鞍带石斑鱼(Epinephelus lanceolatus ♂)的杂交品种(鼠龙斑)抗氧化及消化生理的影响。结果显示，温度渐变组的摄食量、消化酶活性等均比温度突变组高。温度突变组：21℃~32℃的摄食量、消化酶活性均随温度升高而逐渐升高，但35℃有下降趋势。血清中超氧化物歧化酶(SOD)均呈显著上升趋势，35℃组在7 d有所降低，肝脏中SOD在21℃~28℃胁迫前后无显著差异，32℃与35℃呈先下降再回升的趋势。血清和肝脏中过氧化氢酶(CAT)在21~28℃变化趋势一致，均逐渐增加，而32℃与35℃血清与肝脏中CAT的变化趋势完全相反。血清中丙二醛(MDA)在32℃先上升再下降，且变化幅度显著大于其他各组，其他各组均为逐渐降低的状态，肝脏中的MDA均为先升高再降低。温度渐变组：血清中的SOD和CAT均为先上升再下降，肝脏中的SOD在3 d与胁迫前无明显变化，在7 d时显著上升，而肝脏中CAT在3 d和7 d均显著下降；肝脏和血清中的MDA都有逐渐下降趋势。温度突变组中胃蛋白酶与肠道中的脂肪酶在21℃、24℃的变化趋势相似，呈先下降再回升的趋势，其他各组胃蛋白酶呈逐渐上升趋势，脂肪酶先上升再下降，淀粉酶含量低且变化不明显。温度渐变组的胃蛋白酶和脂肪酶都显著增加，淀粉酶变化幅度不显著。综上，温度渐变对鼠龙斑幼鱼摄食和抗氧化性具有促进作用，温度突变对鼠龙斑幼鱼抗氧化性影响明显，胁迫时间延长可能对鱼体肝脏抗氧化体系有损害作用，在实际生产过程中，应该减少急性温度胁迫对鱼体造成的应激反应，可以通过渐变温度驯化达到养殖需求条件。

英文摘要:

      The effects of variable temperature acute change (21℃, 24℃, 28℃, 32℃ and 35℃) and temperature gradient (rising 1℃ every day) on the antioxidant and digestive physiology in hybrid progeny (Mussaurus spot) of Cromileptes altivelis Valenciennes♀× Epinephelus lanceolatus♂ were studied. The results showed that feed intake and digestive enzyme activity in gradual rising temperature group were higher than those in temperature acute change groups. The temperature acute change groups: the feed intake and digestive enzyme activity were gradually increased from 21℃ to 32℃, but decreased in 35℃ group. The serum SOD activities were increased significantly in most temperature mutations groups except 35℃ group at the 7th day. The liver SOD activities had no significant difference before and after treatment in 21℃, 24℃ and 28℃ groups, but decreased in 32℃ group and increased in 35℃ group. The activities of catalase enzyme (CAT) in serum and liver had increasing trends in 21℃, 24℃ and 28℃ groups, but had decreasing trends in 32℃ and 35℃ groups. The serum MDA content increased at first and then decreased in 32℃ group and the amplitude of variation was significantly larger than other groups with gradually decreased content of MDA. The liver MDA content increased at first and then decreased in all groups. The gradual rising temperature group: The serum SOD and CAT activities increased at first and then decreased. The liver SOD activity had no significant change at the 3rd day but significantly increased at the 7th day, while the liver CAT activity decreased significantly at both the 3rd and 7th day. The MDA content in both liver and serum were gradually declined. The temperature acute change groups: the intestinal tract pepsin and lipase activities were similar in 21℃ and 24℃ groups, which decreased at first and then increased. The pepsin activity gradually increased in other groups, while the lipase activity increased at first and then decreased. The amylase activity maintained at a lower level without obvious change. The activity of pepsin and lipase increased significantly in the gradual rising temperature group, while there was no significant change in the amylase activity. In summary, temperature gradual rising can promote the feed intake and antioxidant ability of juvenile Mussaurus spot, while the temperature acute change can make significant effect on antioxidant system and may cause liver damage overtime. So temperature acute change should be limited to reduce the adverse stress response during the feeding time, and temperature gradual rising can be used to achieve the required conditions.