【摘要】 据性腺组织学观察结果和繁殖生物学资料,探讨了福建近海赤点石斑鱼雌性性腺发育规律,对卵母细胞时相、性腺发育期的周年变化、性成熟特性、性转变年龄和生长等方面作了较详细的描述和分析。雌性性腺发育可分为6期,即稚龄、未成熟或产后恢复、正在成熟、接近成熟、成熟流卵和产后期。大多数功能雌性初次性成熟在Ⅲ龄组。功能雌性转变为功能雄性始于Ⅵ龄组。5—9月为生殖季节,5—6月为产卵盛期。雌性每年产卵一次,其性腺发育和成熟系数与水温关系密切。更多还原

【Abstract】 Histological observations were made on the cyclic development of gonads and reproductive biology of female red grouper, Epinephelus akaara, a species of protogynous hermaphroditic fish. The samples were collected monthly from coastal waters along Fujian province of China from April, 1984 to August, 1985. The morphological characters of five phases of the developing oocytes, i.e. juvenile, monlayer follicles, fat accumulated, yolk filled and ripe oocytes, are described. The macroscopical classification of the maturity stages corresponds to definite histological phases of gonad development. The maturation of femald gonae can be divided into six stages(Ⅰ Ⅵ), namely, juvenile, immature or recovering spent, maturing, nearly ripe, ripe and running, and spent stages. The chorion consists of two layers, zona radiata externa and zona radiata interna, in which the radial striations apparently occur for metabolic exchange between follicle oells and oocyte. The degeneration and resorption of oocytes are caused by the phagocytic activities of the follicle cells which have hypertrophied and penetrated into the oocytes, the other regressive pathway involving the autolysis of residual oocytes. Most of functional females first mature at the Ⅲ age group. While the proportion of males increases with their ages, the functional females become the functional males at the beginning of the Ⅳ age group, althought some individuals develop into the functional males at the Ⅴ age group. From November to next February, the gonads of the functional females enter into stage Ⅱ or recovering stage Ⅱ throughout the winter; from March to April, they develop into stage Ⅲ; during the spawning season from May to September, into stages Ⅳ, Ⅴ, Ⅵ, Ⅵ-Ⅱ, Ⅱ and Ⅲ, in August and September, some individuals are still spawning. According to the frequency distribution of ovadiameter, the oocytes of the major growth stage grow synchronously until spawning, so the females spawn once a year. The development of gonads and the maturity coefficient in female are closely related with water temperature. The spawners for induced spawning are discussed too.更多还原