温度对鲢幼鱼游泳能力及耗氧率的影响

Effect of Temperature on Swimming Capability and Oxygen Consumption of Juvenile Hypophthalmichthys molitrix

以鲢(Hypophthalmichthys molitrix)幼鱼(体长10.9～11.8cm,体重16.0～19.0g)为对象,研究了在不同温度(15、18、21、25℃)条件下的游泳能力及耗氧率。结果表明:(1)鲢幼鱼的相对临界游泳速度分别为:(5.30±0.32)、(5.87±0.25)、(6.17±0.16)、(6.85±0.16)BL/s,临界游泳速度随温度升高呈线性增加,拟合方程:Ucrit=3.073+0.150T(R2=0.983,P<0.005)。(2)在同一温度下耗氧率随流速的增加而增加,在同一流速下耗氧率随温度的增加而增加;使用power方程拟合耗氧率与流速关系,4种温度下的速度指数分别为1.41、1.31、1.60、1.80,随着温度的升高而增大。研究结果为水温变化对鱼类影响以及鱼道流速设计提供了鲢幼鱼游泳能力参数。

Swimming capability and oxygen consumption rate of juvenile Hypophthalmichthys molitrix were conducted by a self-designed apparatus at four temperatures. Critical swimming speed was 6.85±0.16, 6.17±0.16, 5.87±0.25 and 5.30±0.32 BL/s, at 15, 18, 21 and 25℃, respectively. There was a significant （p＆lt;0.005） linear correlation between the critical swimming speed（Ucrit） and temperature（T）. The linear function described as Ucrit=3.073＋0.149T, and the increased with the temperature. The relationship between swimming velocity （U） and oxygen consumption （MO2） was fitted by a power function. The result indicated that the oxygen consumption was increasing with the growth of velocity, at all temperatures. And with the increase of temperature, the oxygen consumption and speed exponent increased, thus, the efficiency of energetic decreased. The result of this investigation provides fundamental information about swimming ability of Juvenile Hypophthalmichthys molitrix for intensive studies.