温度对达氏鳇、施氏鲟及其正反杂交种生长的影响

Effect of Temperature on Growth Performance of Huso dauricus,Acipenser schrenckii and Their Hybrids

将体质量(24.55±1.04)g的施氏鲟、达氏鳇及其正反杂交种幼鱼放养在循环水系统中,水温控制在15、18、21、24、27℃和30℃下,常规饲养60d,比较其生长、存活、变异系数和肥满度,以探讨4种鲟鱼幼鱼的最适生长温度。试验结果表明,4种鲟鱼在21~24℃时,生长性能、存活率和肥满度较高;然而,高温和低温对4种鲟鱼的生长、存活和肥满度都产生负影响。在最适温度下,4种鲟鱼体质量增加速度由高至低为达氏鳇>施氏鲟(♀)×达氏鳇(♂)>达氏鳇(♀)×施氏鲟(♂)>施氏鲟。以特定生长率为指标,估算出4种鲟鱼的最适生长水温区间分别为18.67~28.00℃、21.51~31.32℃、21.21~29.64℃和17.81~27.00℃。

Growth, survival, coefficients of variation and condition factor were comparatively investigated in four species of juvenile sturgeons, Amur sturgeon Acipenser schrenckii, Kaluga sturgon Huso dauricus and their reciprocal hybrids reared in a recycling system at water temperature of 15 ℃, 18 ℃, 21 ℃, 24 ℃, 27 ℃ and 30 ℃ for 60 days in order to assess the optimum temperature for growth. The results showed that significantly higher growth performance, survival rate and condition factor were observed in the fish exposed to 21 ℃ and 24 ℃, while these variables were drastically decreased in the fish with expo- sure to higher or lower thses water temperature. At the optimal growth temperature, the maxiaml weight gain was found in H. dauricus, followed by the hybrid [-A. schrenckii（ ♀ ） ）〈 H. dauricus（♂ ）], hybrid [H. dauricus（♀ ）xA. schrenckii（♂ ）] and then A. schrenckii. The ranges of optimal water temperature for the four species of juvenile sturgeons were shown to be changed from 18. 67 ℃ to 28. 00 ℃ in A. schrenckii, from 21.51 ℃ to 31.32 ℃ in hybrid [A. schrenckii（♀）X H. dauricus（♂ ）], from 21.21 ℃ to 29.64 ℃ in hybrid [A. schrenckii（♂ ）XH. dauricus（♀）], and from 17.81 ℃ to 17.81 ℃ in H. dau- ricus.