短须裂腹鱼有氧游泳能力及其行为的实验研究

Experimental Study on Aerobic Swimming Performance and Behavior of Schizothorax wangchiachii Fang

研究短须裂腹鱼的游泳能力、运动生理及游泳行为,为过鱼设施的设计提供参考依据。实验用15尾短须裂腹鱼于2013年7月中旬采自金沙江上游玛曲河河口处,体长（23.83±2.47）cm,体重（224.95±76.83）g。游泳能力测试装置采用丹麦Loligo Systems公司生产的大型游泳水槽。（1）短须裂腹鱼临界游泳速度为（75.04±7.6）cm/s、（3.17±0.42）BL/s;（2）运动耗氧率与游泳速度呈幂函数关系：MO2=100.00＋42.61U1.81（R2=0.995,P〈0.001）;单位距离耗氧率（COT）与游泳速度的关系也呈幂函数关系：COT=0.12U-1＋0.04U1.02（R2=0.898,P〈0.001）,最适游速Uopt=1.81 BL/s,COTmin=0.14 mg/（kg·m）;（3）随着游泳速度的增加,尾摆幅度的变化不显著（P〉0.05）,变化范围为0.17~0.26 BL、平均（0.21±0.02）BL,而尾摆频率和运动步长都呈线性增加的趋势。

Schizothorax wangchiachii Fang,endemic to the upper Yangtze River,is an important economic fish in the Jinsha and Yagong Rivers. With hydropower development on these rivers,wild Schizothorax wangchiachii Fang populations are threatened by habitat fragmentation and it has become the primary species targeted for fish passage.To provide basic data for the design of fish pass facilities,we examined the swimming performance,energetic and kinematic characteristics of wild Schizothorax wangchiachii Fang in a swim tunnel respirometer. Test fish were captured in the upper Jinsha River with body length of（ 23. 83 ± 2. 47） cm and body mass of（ 224. 95 ± 76. 83） g.The fish were acclimated for three days at 12. 1- 16. 1℃ and DO of 7. 0 mg / L. The swim tunnel had a large swim channel（ 70 cm × 20 cm × 20 cm） and the circulating water was taken from the fish storage pond. At the beginning of the test,one fish was put in the swim chamber at a flow velocity of 0. 5 BL / s and acclimated for 1 h. The flow velocity was then increased 0. 5 BL / s each 20 min until the fish was exhausted. During each time interval,the water was exchanged for the first three min to maintain DO〉 7 mg / L,the respirometer was then sealed and the DO was measured three times at 5,10 and 15 min. Results show that：（ 1） The critical swimming speed（ Ucrit） of Schizothorax wangchiachii Fang is（ 75. 04 ± 7. 6） cm / s（ 3. 17 ± 0. 42 BL / s）.（ 2） Oxygen consumption,as a function of swimming speed,was fit to the equation： MO2= 100. 00 ＋ 42. 61U1. 81（ R2= 0. 995,P〈 0. 001）,and the relationship between cost of transport and swimming speed was described as： COT = 0. 12U- 1＋ 0. 04U1. 02（ R2= 0. 898,P〈 0. 001）. The optimum swimming speed（ Uopt） was 1. 81 BL/s and the corresponding energetic cost was 0. 14 mg /（ kg·m）.（ 3） The tail beat frequency（ TBF） and stride length（ Ls） both increased linearly with the swimming speed： TBF = 66. 60 ＋ 61. 98U（ R2= 0. 990,P〈 0. 001） and Ls = 0. 47 ＋ 0. 08U（ R2= 0. 994,P〈 0. 001）. Tail beat amplitude did not change significantly with swimming speed（ 0. 17- 0. 26 BL,P〉 0. 05）and average tail beat amplitude（ TBA） was（ 0. 21 ± 0. 02） BL. This research provides basic data for the design of fish passage facilities,of great importance for the conservation of wild Schizothorax wangchiachii Fang.