【摘要】 研究辽河流域鲇种群生殖适应性，即个体生殖力及其调节机制、生殖过程及其适应性。结果表明：鲇个体生殖力低于鲤科鱼类而与乌鳢和胡子鲇相近，卵质优于鲤科鱼类；鲇产卵期长，有利于亲鱼充分利用产卵场和仔鱼利用饵料资源；产卵后卵巢内有大量的卵母细胞残留是对不稳定生殖环境的适应。更多还原

【Abstract】 From 1995 to 1997, 99 female samples of Silurus asotus were captured in Liaohe River, body weight ranging from 260 g to 2 970 g. From those samples the individual fecundity, reproductive process and adaptability were studied. The results show that the individual absolute fecundity (F) and individual relative fecundity (F/L or F/ W) increase with the increase of age within 1～5 years old; and with the increase of body length (L) or body weight (W), F and F/L increase, but F/ W declines. The total weight of 100 eggs at age of 2 ～3 years is heavier than that at age of 4 ～5 years. During annual cycle, the seasonal variation of their F is relatively steady; the GSI (gonad somatic index) goes up month by month during April to July, and gets to the peak in July, then goes down and to the lowest point in September, and then goes up again month by month. However, the LSI (liver - somatic index) changes contrary to GSI. The spawning period of catfish is from April to August but the higher spawning rate appears between the end of May and the end of July. Compared with other species of fishes, the F of catfish is lower than some other species of Cyprinidae but similar to Chinese snakehead (Channel argus ) and whitespotted freshwater catfish (Clarias fuscus ), and the eggs of catfish have better quality (egg weight and size) than carps; their spawning period lasts longer so that the spawning spots can be utilized fully by breeding fish and the diet resource can be best used by the larvae. The observation shows that there remains large of oocytes in the ovary after spawning. Maybe that is just the adaptability of S. asotus to the changes of environment in this river.更多还原