犬齿牙鲆幼鱼呼吸耗氧率的研究

Study on Respiration and Oxygen Consumption Rate of Summer Flounder(Paralichthys dentatus) Juvenile

对犬齿牙鲆幼鱼在不同环境条件下的呼吸频率、耗氧率以及窒息浮头现象进行了观测研究。结果表明:犬齿牙鲆在适宜温度范围,呼吸频率随温度的升高而加快,在适宜生长温度范围,其呼吸频率为60～100次/min。耗氧量与鱼体重正相关,二者之间的相关关系符合M=1.8469W0.8317(r=0.9116)模式。其耗氧率随温度和盐度的增加而增加,在水温20℃左右,体重108g的犬齿牙鲆24h平均耗氧率为1.6676μg/(min·g),明显低于褐牙鲆(体重69.3～151.4g)耗氧率2.68μg/(min·g)和大菱鲆(17℃体重70～110g)耗氧率3.4667μg/(min·g)的水平。其耗氧率白天为1.824μg/(min·g),夜间为1.511μg/(min·g),白天耗氧率是夜间的1 21倍,昼夜差异明显。犬齿牙鲆20℃半数死亡窒息点耗氧率为0 747mg/L,全部死亡窒息点耗氧率为0 569mg/L。

The observations and studies on the respiration frequency, oxygen consumption rate and asphyxia of summer flounder juvenile were made, and it is shown from the study results that the respiration frequency of juvenile increased with increasing water temperature and was 60 to 100 times/min in the range of suitable water temperature; the oxygen consumption was in positive correlation with the fish weight, and their correlation was M=1.8469 W^(0.8317)(r=0.9116). The oxygen consumption rate increased with increasing water temperature and salinity, and the mean oxygen consumption rate of 108 g fish at about 20 ℃ within 24 hours was 1.6676 μg/(min·g), which is lower than those of Japanese flounder(2.68 μg/(min·g)) and turbot (3.4667 μg/(min·g)). The daytime oxygen consumption rate was 1.824 μg/(min·g), and the night one was 1.511 μg/(min·g), so the daytime one is 1.21 times the night one. The half lethal suffocation point of summer flounder at 20 ℃ was 0.747 mg/L, and the full one was 0.569 mg/L.