不同流速对许氏平鲉生长及行为的影响

文章以许氏平鲉(Sebastes schlegelii)幼鱼为研究对象,研究了不同流速对许氏平鲉幼鱼生长性能和行为表现的影响。实验共设置4个流速处理组,分别为0(C组)、0.5 BL/s(L组)、1.5 BL/s(M组)和2.5 BL/s(H组),实验周期为43d。研究共监测与分析了8个行为指标,并将其归为运动参数(平均速度和最大加速度)、偏好区域(内、中和外圈累计停留时间)和活动状态(最大轮替次数、活跃性和身体接触)等3类行为状态。结果表明:(1)在整个实验周期中, M组和L组的终体长显著高于C组和H组(P<0.05); M组的终体重、特定生长率和增重率显著高于C组和H组(P<0.05)。(2)在实验30d后, M组和H组的外圈累计停留时间显著低于C组和L组(P<0.05),且M组中圈累计停留时间显著高于C组和H组(P<0.05); H组的中圈累计停留时间显著低于其他处理组(P<0.05),其内圈累计停留时间显著高于其他处理组(P<0.05),且各处理组间没有显著差异(P>0.05); M组的最大加速度显著高于C组和L组(P<0.05)...

FLOW VELOCITY ON GROWTH AND BEHAVIOR IN BLACK ROCKFISH (SEBASTES SCHLEGELII)

In order to investigate the growth and behavior of juvenile black rockfish (Sebastes schlegelii) under different flow velocities, four treatment groups were set up. The average water flows velocity of the four treatments was maintained at 0, 0.5, 1.5, and 2.5 BL/s, expressed as C, L, M, and H, respectively. The experiment lasted for 43d and eight behavior indicators were analyzed. The results showed the following: (1) The final body lengths in M and L were significantly higher than those in the other two treatment groups (P<0.05); the final weight, specific growth rate and weight gain rate were significantly higher in treatment M than those in treatment C and H (P<0.05); the feed conversion ratio was significantly lower in treatment L than that in treatment H (P<0.05). (2) After 30d of the experiment, the accumulated residence time of the outer-circle area was significantly lower in both the M and H treatment groups compared with C and L treatment groups (P<0.05); the accumulated residence time in the middle-circle area was significantly higher in M and L treatment groups (P<0.05); the accumulated residence time of inner-circle area in treatment H was significantly higher than that in other treatment groups (P<0.05); the maximum accelerations of M were significantly higher than those of C and L treatment (P<0.05), after 36d of the experiment, the average velocity of the M treatment was significantly higher than that in the other treatment groups (P<0.05). In conclusion, moderate swimming training significantly improved the growth performance of juvenile black rockfish, and the optimal flow velocity occurred at 1.5 BL/s under the present experimental conditions. Flow velocity significantly influenced the behavioral characteristics of juvenile black rockfish. Behavioral characteristics, such as regional preference and activity status, could be used to assess the respond of juvenile black rockfish to various water flow velocities.