张家口坝上高背型鲫鱼耗氧率和窒息点的初步研究

Preliminary Study on Oxygen-consuming Rate and Suffocation Point for High-backed Carassius auratus from Bashang in Zhangjiakou

研究张家口坝上两个规格高背型鲫鱼在不同温度下的耗氧率和临界窒息点。结果显示:在水温24.9～33.0℃条件下,体长76.13±4.66 mm、体质量7.56±1.48 g的小规格鱼24 h平均耗氧量为0.220±0.087 mg/(尾.h),耗氧率为0.029±0.012 mg/(g.h),窒息点为0.03 mg/L;在水温12.4～13.4℃条件下,体长153.00±6.66 mm,体质量53.43±6.59 g的大规格鱼24 h平均耗氧量为0.506±0.145 mg/(尾.h),耗氧率为0.010±0.003 mg/(g.h),窒息点为0.02 mg/L。高背鲫鱼耗氧率存在明显的昼夜变化,昼间高于夜间,并在7:00-9:00、15:00-17:00出现两个高峰。该鱼窒息点极低,在溶解氧较低的环境下仍能存活,并且达到窒息点的耗时与水温密切相关。

The oxygen-consuming rate and the critical suffocation point have been determined for two sizes of the high-backed Carassius auratus. The results showed that under the conditions of water temperature at 24.9 - 33.0℃, the small size fish, with average length of 76.1 mm and average weight of 7.56 g, had the average oxygen consumption of 0.22 mg / （ind·h） within 24 hours, and the oxygen-consuming rate was 0.029 mg / （g·h）, and the suffocated point was 0.03 mg / L. Under the conditions of water temperature at 12.4 - 13.4℃, the large size fish, with the average length of 153.0 mm and the average weight of 53.43 g, had the average oxygen-consuming of 0.51 mg / （ind·h） within 24 hours, and the oxygen consumption rate was 0.010 mg / （g·h）, and the suffocation point was 0.02 mg/L. The oxygen-consuming rate of the high-backed C. auratus varied significantly from day to night, and it was higher at daytime than that at night, and two peaks of the oxygen-consuming rate appeared at daytime. The fish had an extremely low suffgcation point and could survive the extreme oxygen-deficient. The time-consuming of achieving the suffocation point was closely related with water temperature.