短期饥饿对大口黑鲈幼鱼自发运动和力竭运动后代谢的影响

Effect of Short-Term Starvation on Spontaneous Activity and Excess Post-Exercise Oxygen Consumption of Juvenile Micropterus salmoides

【目的】考察短期饥饿对大口黑鲈(Micropterus salmoides)幼鱼自发运动和力竭运动后代谢(EPOC)影响。【方法】在(25±1)℃条件下将体质量为(13.34±0.32)g、体长为(8.92±0.07)cm的40尾大小相似的大口黑鲈幼鱼随机平均分为持续正常饲喂饵料的对照组和持续禁食14 d的饥饿组,并测定实验鱼的自发运动指标及EPOC相关参数。【结果】1)饥饿组体质量低于对照组体质量,两者差异具有统计学意义(p<0.05);2)在运动平均速度、单位时间内运动总距离和运动时间百分比方面,饥饿组均高于对照组,有关差异均具有统计学意义(p<0.05);3)饥饿组运动前代谢率和运动后代谢峰值均较对照组的这两项指标更低,有关差异均有统计学意义(p<0.05);4)饥饿组与对照组的峰值时间、代谢率增量、过量耗氧和恢复速率均无统计学意义上的差异。【结论】大口黑鲈幼鱼在短期饥饿后主要通过增加运动时间来提高自身自发运动水平,并采用下调有氧运动代谢和维持无氧运动代谢的策略应对短期饥饿胁迫。

[Purposes]To investigate the effects of short-term starvation on spontaneous activity and excess post-exercise oxygen consumption(EPOC) in juvenile Micropterus salmoides. [Methods]40 juvenile M. salmoides with similar body of((13.34±0.32) g,(8.92±0.07) cm) were randomly divided into control group(continuous feeding) and starved group(starvation for 2 weeks), and then measured the spontaneous activity and EPOC response of experimental fish at 25 ℃. [Findings]The body weight of the starved group was significantly lower than that of the control group(p<0.05). Total movement distance, average swimming speed and percent time spent moving in the starved group were significantly higher than those in the control group(p<0.05). The pro-exercise and peak post-exercise M;in the starved group were significantly lower than those in the control group. There were no significant differences in time to peak, increment of metabolic rate, EPOC magnitude and recovery rate of metabolic rate between the starved group and the control group. [Conclusions]1) Short-term starvation leads to the juvenile M. salmoides to increase its spontaneous activity level mainly by increasing the exercise time. 2) Juvenile M. salmoides adopt the strategy of decreasing aerobic exercise metabolism and maintain anaerobic exercise metabolism to cope with short-term starvation stress.