乌苏里拟鲿对水温环境的适应性

Water temperature adaptability of Pseudobagrus ussuriensis

【目的】明确乌苏里拟鲿对水温环境的适应性,为将其引种到我国南亚热带地区推广养殖提供参考依据。【方法】探究分析乌苏里拟鲿对水温突变温差的极限适应性,并研究不同水温条件下的摄食强度、繁殖和血液指标。【结果】乌苏里拟鲿对从高温突变到低温环境的忍耐力温差在8.0℃以内,而对从低温突变到高温环境的忍耐极限温差为7.0℃。乌苏里拟鲿摄食率与水温呈抛物线相关,对应的线性回归方程为y=-0.0132x2+0.6953x-5.0973(R2=0.7661)。在11.8~30.3℃的水温范围内,乌苏里拟鲿生长常数(GC)为0.1464~0.7620,基本不受高温环境的影响。在25.8℃水温条件下,乌苏里拟鲿的催产率、受精率、孵化率及出膜30 d后存活率均最高,分别为73.4%、84.1%、82.6%和75.7%,即乌苏里拟鲿孵化的最佳水温约25.0℃。乌苏里拟鲿在30.0℃以内的水温条件下尚能保证机体组织器官的完整性,并发挥正常的生理功能。【结论】乌苏里拟鲿对水温环境具有极好的适应性,对±7.0℃的温差有很好的应激适应性,可引种到我国南亚热带地区推广养殖,但在运输和越冬养殖过程中,若温差应激的强度过大或时间过长,其生理适应机制可能会失效,因此在乌苏里拟鲿引种养殖过程中应予以重视。

【Objective】The adaptability of Pseudobagrus ussuriensis to water temperature was clarified to provide references for its introduction and aquaculture in southern subtropical regions of China.【Method】The paper explored and analyzed the extreme temperature difference adaptability of P.ussuriensis,and studied the feeding intensity,breeding and blood parameters under different water temperature conditions.【Result】The tolerance range limit of P.ussuriensis mutated from high temperature changing to the low temperature was 8.0℃,and the tolerance limit range from low temperature to high temperature was 7.0℃.Its daily feeding rate were in parabolic relation with temperature,the corresponding equation of linear regression was y=-0.0132x2+0.6953x-5.0973(R2=0.7661).In the range of 11.8℃to 30.3℃,P.ussuriensis growth constant(GC)was between 0.1464 and 0.7620.It was basically not affected by high temperature.At the water temperature of 25.8℃,its oxytoic rate,fertilization rate,incubation rate and survival rate 30 d after hatching were the highest,which were 73.4%,84.1%,82.6%and 75.7%.Therefore,the optimum water temperature for hatching was about 25.0℃.P.ussuriensis could maintain the integrity of its body tissues and organs and normal physiological function within 30.0℃.【Conclusion】The result shows that,P.ussuriensis has excellent adaptability to water temperature environment,especially for±7.0℃water temperature difference.It can be introduced into the southern subtropical region of China to promote aquaculture.But if the intensity of temperature difference stress is too strong or the time is too long during the transportation and overwinter cultivation,its physiological adaptation mechanism may fail.Therefore,attention should be paid to the introduction of P.ussuriensis.