以圆口铜鱼(Coreius guichenoti)幼鱼为研究对象,通过自制的鱼类游泳实验装置,测定了4个温度(10,15,20和25℃)下圆口铜鱼幼鱼游泳速度达到临界游速过程中及运动疲劳后耗氧率的变化情况;在自然水温条件下,测定了5个不同流速下的可持续游泳时间,并通过摄像记录分析了不同游泳速度下的游泳行为。结果显示:圆口铜鱼幼鱼在运动疲劳前耗氧率随流速的增加显著上升(P〈0.05),在临界游速时达到峰值;运动疲劳后耗氧率逐渐下降,40~50 min内耗氧率恢复至低流速时的水平。自然水温(18.0±1.5)℃条件下幼鱼的可持续游泳时间随流速增加逐渐减小(P〈0.01),在1.31倍临界游速的固定流速下,平均可持续游泳时间达29 min,体现了较强的游泳耐力及无氧代谢能力。录像分析表明,摆尾频率(TBF)与游速的关系呈线性正相关(P〈0.001),且随着温度升高,TBF随流速增加的趋势越明显。
To obtain data that can be applied to the design of an effective fishway for Coreius guichenoti,and other species in the fish community,a laboratory study of juvenile C. guichenoti's swimming ability and energetics was conducted in a flume-type respirometer. The oxygen consumption rate( MO2) before and after swimming fatigue were determined during steady swimming to reach the critical swimming speed( Ucrit) at four water temperatures( 10 ℃,15 ℃,20 ℃ and 25℃). The endurance swimming time at five swimming speeds was determined at natural water temperature. The swimming behavior was recorded with a high speed video camera system during the MO2 protocol. Before swimming fatigue,MO2 increased with the increase of swimming speed and reached the maximum at the Ucrit. Following exhaustion at Ucrit,recovery time was 40 ~ 50 min. Results show that temperature has a significant effect on swimming performance. The endurance swimming time decreased with the increase of flow velocity at 18. 0 ± 1. 5 ℃( P 0. 01) but reach 29 min at 1. 31 Ucrit,showing high swimming endurance and anaerobic metabolic capacity. There was a significant positive linear correlation between tail beat frequency( TBF) and swimming speed( P 0. 001) and the increase is more significant as the temperature is higher.