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赤眼鳟在长江流域曾广为分布,是一种重要的江河经济鱼类。2002～2004年,对产于长江一级支流府河孝感段及其附属湖泊,如野猪湖、王母湖和府河的一级支流———环河中的赤眼鳟进行了多次资源调查。通过对采自不同月份的186尾赤眼鳟标本进行解剖,测量了Ⅳ～Ⅴ期卵巢中卵母细胞的直径。Ⅳ期末卵巢中,Ⅱ～Ⅲ时相的卵细胞直径为0.39～0.52mm,卵细胞数占7.4%;IV～V时相的卵细胞直径为0.94～1.04mm,卵细胞数占92.6%;测定周年性成熟系数,其峰值出现在7月,雌鱼平均为28.8%,雄鱼为1.27%,刚产过卵的Ⅵ期卵巢,性成熟系数仅为0.78%,其卵巢切片显示很少见到Ⅲ、Ⅳ时相的卵母细胞。根据测定的卵母细胞的直径和性成熟系数可以推断,赤眼鳟的产卵类型应为一次型而不是分批产卵型。解剖的186尾标本,其中雌鱼96尾,雄鱼90尾,性比为1.07∶1,接近1∶1。对赤眼鳟的繁殖与保护应该引起高度关注。
Red-eye trout in the Yangtze River Basin has been widely distributed, is an important river economic fish. From 2002 to 2004, a number of resource surveys were conducted on red-thread trout produced in the Xiaohe River, a tributary of the Fujiang River, a tributary of the Yangtze River and its sub-lakes, such as the first tributary of the Wild Pig Lake, Wang mother lake and Fu River. The diameter of oocytes in stage Ⅳ ~ Ⅴ ovaries was measured by dissecting 186 specimens of red eye trout collected from different months. At the end of stage IV ovary, the diameter of oocytes from stage Ⅱ to Ⅲ was 0.39 ~ 0.52mm and the number of oocytes was 7.4%. The diameter of oocytes from IV to V was 0.94 ~ 1.04mm and the number of oocytes was 92.6%. The annual maturation coefficient , The peak appeared in July, the average of females was 28.8% and males was 1.27%. Stage Ⅵ ovarian oviparity was just produced. The sexual maturity coefficient was only 0.78%. The ovarian sections showed very few Ⅲ and Ⅳ Phase of the oocyte. Based on the measured oocyte diameter and sexual maturity coefficient, it can be deduced that the type of ovipositing of red-thread trout should be one-time rather than batch-wise spawning. 186 anatomical specimens, of which 96 females, 90 males, sex ratio of 1.07: 1, close to 1: 1. Breeding and protection of red trout should arouse great concern.