摘要
细鳞鱼是一种名贵的冷水性鱼类,只分布于苏联,朝鲜、蒙古和中国。本文报导水温、pH、体重、剧烈活动和食物等内外因素对细鳞鱼耗氧代谢影响的研究结果。
Fine-scale salmon, Brachymystax lenok (Pallas) , is a kind of rare fish living in cold waters. It is only distributed over the Soviet Union, Korea, Mongolia and the north of China. However, its natural population quantity has been declining year by year in our country and it is in imminent danger in Hebei province. Some scholars have carried out the basic research on fine-scale salmon in our country and the Soviet Union as well. But we have found that the research of physiological ecology for fine-scale salmon is blank at home and abroad. This paper reports the studies on the effects of water temperature, pH, body weight, acute activities and digestion on oxygen metabolism of fine-scale salmon in order to understand the primary limiting factors of reproduction and distribution of this fish, return to its population and achieve artificial reproduction for it. Moreover, its energy consumption of digesting food is estimated. Our research work have obtained the following results. 1) Though oxygen consumption of fine-scale salmon will increase with water temperature, its resting oxygen consumption only increases 1.25-2.45 times when water temperature is raised by 10℃ (from 9℃ to 19℃) .That is to say that the increa sing multiple of resting oxygen consumption for the fish may be lower than other species of salmonoid. It may live in the water of 22℃. 2) Its optimum pH is about 6.75. If the value of pH is changed from the range of 5.75 to 7.80, the oxygen consumption will increase largely. Its upper lethal limit is pH 8.509 and lower limit is pH 4.30. 3) The more body weight, the less oxygen consumption of unit weight has. We may calculate the largest quantity of finescale salmon held in the fixed volume of cultural waters according to the formulas we have obtained from the relation between resting oxygen consumption (M) and body weight (W) in different water temperature— M (t=9℃)=0.5248W^(-0.5597), M (t=13℃)=0.558W^(-0.4419), M (t=17℃)=0.4602W^(-0.3278) and M (t=19℃)=0.5589W^(-0.3302). 4) Active oxygen consumption is 6-7 times higher than resting oxygen consumption.
