水温和摇晃对黑鲷幼鱼运输生存状态的影响

Preliminary studies on the effects of the temperature and shaking on transport and survival of juvenile black seabream(Acanthopagrus schlegelii)

摘要:

为探讨运输过程中水温和摇晃因素对增殖放流种类幼体存活率的影响，以黑鲷（Acanthopagrus schlegelii）幼鱼为实验对象，研究在不同水温和摇晃频率条件下运输水体氨氮质量浓度、黑鲷幼鱼肌肉乳酸浓度和糖元质量分数的变化。结果表明，随实验水温的升高，水体氨氮质量浓度上升，黑鲷幼鱼肌肉乳酸浓度先上升后下降，肌肉糖元质量分数先下降后上升，黑鲷幼鱼存活率随之下降，21~25℃是适宜的水温。随实验摇晃频率的增加，水体氨氮质量浓度上升，黑鲷幼鱼肌肉乳酸浓度和糖元质量分数分别增加和降低，黑鲷幼鱼存活率随之下降。建议规格为5 cm左右的黑鲷幼鱼在运输前对其进行拉网锻炼，以及进行水温和摇晃等胁迫因子耐受性训练，运输时水温不宜超过其室内培育条件下的水温，以21~25℃为宜，可以低于其室内培育条件下的水温，但温差不宜超过4℃，同时运输时的摇晃频率不宜超过105 r/min。

Abstract:

In order to investigate the influences of water temperature and vehicle swaying on the survival rate of juvenile fish for stock enhancement during the process of transportation, the changes of environmental water ammonia nitrogen mass concentration, the changes of muscular lactic acid concentration and glycogen mass fraction of juvenile Acanthopagrus schlegelii, at different water temperature and different levels of swaying simulation. When the environmental water temperature was elevated, increased ammonia nitrogen concentration in water was observed, while the muscular lactic acid concentration of juvenile fish increased at early stage and then decreased later, whereas the muscular glycogen mass fraction of juvenile fish varied in the opposite way, decreased at early stage and then increased later. The survival rate of juvenile fish dropped significantly with the increase of environmental water temperature, and 21 to 25℃ were regarded as optimal water temperature. In the swaying simulation experiments, when the swaying frequency of environmental water was enhanced, increased ammonia nitrogen mass concentration in water was observed, while the juvenile fish was observed with increased muscular lactic acid concentration and decreased muscular glycogen mass fraction. The survival rate of juvenile fish dropped significantly with the enhancement of environmental water swaying. It is recommended that the black sea bream juveniles with a size of about 5 cm should be trained for the black sea bream juveniles before transport, and the stress factors such as water temperature and shaking should be trained. The water temperature during transportation should not exceed the water temperature under the indoor cultivation conditions. 21-25℃ are appropriate, and can be lower than the water temperature under its indoor cultivation conditions, but the temperature difference should not exceed 4℃, while the shaking frequency during transportation should not exceed 105 r/min.