青鱼逃逸过程中的疾冲-滑行游泳行为

The Burst-coast Behavior in Escape Response of Black Carp

本实验以青鱼(Mylopharyngodon piceus)为研究对象,定性分析了通过电击实验鱼受到惊吓而产生的快速逃逸游泳行为,并定量分析了其疾冲游泳过程中加速度、最大疾冲游泳加速度和减速过程中的加速度。在自然光照下,保持实验水温为(20.0±1.0)℃。青鱼的3种不同体长规格分别为稚鱼(9.21±1.89)cm(n=30)、幼鱼(17.83±2.67)cm(n=30)和亚成体(61.45±0.80)cm(n=10)。实验过程中发现实验鱼逃逸游泳行为主要以疾冲-滑行的游泳方式进行,即实验鱼到达最大疾冲速度后身体保持固定直线不变的形式减速。3种体长实验鱼对应的最大绝对逃逸速度分别为(1.261±0.279)m/s、(1.542±0.280)m/s和(2.292±0.567)m/s,到达最大逃逸速度的时间分别为(0.249±0.089)s、(0.293±0.067)s和(0.216±0.024)s,其对应的最大相对逃逸速度,即实验鱼每秒内游泳距离相对于体长(BL)的倍数(以BL/s作为单位),分别为(13.694±3.032)BL/s、(8.648±1.571)BL/s和(3.729±0.923)BL/s。单因素方差分析表明,实验鱼的绝对疾冲速度随体长的增加而增加,亚成体的最大疾冲游泳速度显著大于稚鱼(P<0.05);相对疾冲速度随体长的增加而减小,3种实验鱼之间的最大相对疾冲游泳速度均存在显著性差异(P<0.05);亚成体的绝对滑行游泳加速度的绝对值显著高于幼鱼和稚鱼(P<0.05)。3种实验鱼之间的相对滑行加速度不存在显著性差异(P>0.05)。

This experiment studied the escapement behavior of black carp（ Mylopharyngodon piceus）. The rapid escapement behavior of tested fish triggered by electric shock was analyzed qualitatively,and the acceleration, maximum acceleration and deceleration during sprinting were analyzed quantitatively. The experiment was conducted in natural light condition with water temperature of 20. 0 ± 1. 0 ℃. The tested fish were categorized to 3 groups according to body length： young fish 9. 21 ± 1. 89 cm（ n = 30）,juvenile fish17. 83 ± 2. 67 cm（ n = 30）,sub-adult fish 61. 45 ± 0. 80 cm（ n = 10）. The results showed that the maximum absolute escape speeds of tested fish corresponding to 3 different size groups were 1. 261 ± 0. 279 m / s,1. 542 ±0. 280 m / s and 2. 292 ± 0. 567 m / s,the time to reach the highest sprinting speed were 0. 249 ± 0. 089 s,0. 293± 0. 067 s and 0. 216 ± 0. 024 s,the maximum relative escape speeds [the unit of relative speeds of test fish was BL / s of which speed was divided by body length（ BL） ] were 13. 694 ± 3. 032 BL / s,8. 648 ± 1. 571 BL /s and 3. 729 ± 0. 923 BL / s. Fish slowed down to coast with the body kept steady（ no tail-beat） when test fish reached the best sprinting speed. One-way ANOVA. difference analysis showed that the absolute sprinting speed of tested fish increased as body length increased and sub-adult fish（ 61. 45 ± 0. 80 cm） had a faster absolute sprinting speed than young fish（ 9. 21 ± 1. 89 cm）（ P 〈 0. 05）（ Fig. 2）; while the relative sprinting speed of tested fish decreased as the body length increased,presenting significant difference in the maximum relative sprinting speed among the 3 tested groups（ P 〈 0. 05）（ Fig. 4）; the value of absolute coast deceleration of the Sub-adult fish significantly higher than that of the Young fish or Juvenile fish（ 17. 83± 2. 67 cm）（ P 〈 0. 05）（ Fig. 5）; there is no significant difference in the relative coast acceleration among the 3 tested groups（ P 〉 0. 05）（ Fig. 5）.