低温胁迫对乌鳢、斑鳢及其杂种血清生化指标的影响

Effects of Low-temperature Stress on Serum Biochemical Indexes in Channa argus,Channa maculata and Their Hybrids

本实验探讨了骤降、缓降两种不同降温模式下低温胁迫对乌鳢(Channa argus)、斑鳢(Channa maculata)及其杂种斑乌鳢(C.maculata♀×C.argus♂)、乌斑鳢(C.argus♀×C.maculata♂)血清生化指标的影响。具体的实验方法为,将4种鳢分别以6℃/24 h、1℃/24 h的速率从18℃降至2℃,在18℃、12℃、6℃、2℃4个温度点维持12 h,取样,抽血,制备血清,测定生化指标。结果表明,两种降温模式下,多数酶活性胁迫后显著高于胁迫前(p<0.05),但急降组谷草转氨酶(GOT)和缓降组谷胺酰转肽酶(GGT)活性显著低于胁迫前(p<0.05);甘油三酯(TG)含量显著低于胁迫前(p<0.05),血糖(Glu)含量与之相反;血钠(Na+)、氯(Cl-)浓度变化趋势相似,均显著降低(p<0.05);总蛋白(TP)含量低于胁迫前,其中斑鳢波动幅度最大,波动范围为(26.4±2.91)^(43.1±1.81)mmol/L。两种降温模式比较,胁迫后急降组GPT、GGT活性及Na+、Cl-含量高于缓降组,而GOT、ALP、LDH活力及Glu、K+、Ca2+含量与之相反。本实验研究认为,低温胁迫后所有鳢的肝脏、心肌等组织器官均出现了不同程度的损伤,缓降跟骤降模式下各指标变化规律也不完全一致,斑鳢耐低温能力最弱,长期处于6℃以下将致死;4种鳢各种生理指标变化趋势差异较大,纯种间或杂交种间具有相似趋势,表明杂交种与父母本生理过程变化不同,并为鳢低温胁迫研究提供一些基础性数据。

This study investigated the effects on serum biomarkers in four fish, including Channa argus, Channa maculata, and the hybrids （C. maculata ♀ ×C. argus ♂ and C. argus ♀. ×C. maculata ♂ ） caused by low temperature （acute or gradient temperature decreasing）. The specific experimental method was that lower the temperature of the four Channa at the rate of 6℃/24 h, 1℃/24 h respectively from 18℃ to 2℃. Dropped to 18℃, 12℃, 6℃, 2℃, maintained temperature 12 h, then taken samples, drawn blood, prepared serum and detect serum biochemical markers. The results showed that with gradient temperature decreasing, the activities of most enzymes were significantly increased in all the Channa （p〈0.05）, but the activities of GOT in acute temperature decreasing and GGT in gradient temperature decreasing were the opposite （p 〈0.05）. Under the two conditions, acute or gradient temperature decreasing, the level of TG was apparently decreased, the level of Glu was quite the contrary. The concentration of serum Na^＋ and CI were significantly decreased （p 〈0.05） and the change ranges were similar. The amount of total protein （TP） became decrease after the low temperature stress in all fish, but the fluctuation range of C. maculata was the largest, from （26.4±2.91） to （43.1 ± 1.81） mmol/L. Compare the two modes, the levels of GOT, GPT, Glu, K^＋ and Ca^2＋ in acute temperature stress were higher than that in chornic temperature stress, but the levels of GGT, ALP, LDH, Na^＋ and Cl^- were the opposite. The results proved that the low temperature caused damages on liver and heart at different degrees in all fish and the fluctuations of biochemical indicators were different in two modes. C. maculata was the least resistance to low temperature, it died under 6℃ for a long time. The findings here implied that similar patterns and different physiological changes appeared in C. argus and C. maeulata, or the two hybrids, when challenged with low temperature. And serum biochemical parameters could provide some basic data for the low temperature stress study in Channa.