湖泊放养长江水系中华绒螯蟹的性成熟规律研究

STUDIES ON GONAD DEVELOPMENTAL RULE OF LAKE STOCKED MITTEN CRAB OF YANGTZE POPULATION

于 8— 1 1月份 ,结合中华绒螯蟹捕捞期 ,即生殖洄游期的到来 ,通过性腺发育的组织学和细胞学观察 ,重点观察了长江下游安徽杨赛湖等人工放养长江水系中华绒螯蟹的性成熟规律。结果表明 :①在性成熟时期 ,性腺发育与肝胰脏变化极为密切 ,肝脏指数逐渐下降 ,而性腺指数逐渐上升 ;②雌、雄蟹的性成熟存在规律性差异 ,8— 9月份 ,雄蟹的性腺指数和性 /肝指数均高于雌蟹 ,而 1 0— 1 1月份 ,雌蟹的性腺指数和性 /肝指数均高于雄蟹 ;③经性腺的组织学和细胞学观察 ,雄蟹的性腺发育略早于雌蟹 ;④洄游高峰期的出现是河蟹性细胞走向成熟的外在表现。作者建议把肝脏指数 7 5作为捕捞长江水系河蟹最佳时机的指标。

Combined with catch curve, histological and cytological observation of gonad, the maturity development from August to October of mitten crab stocked in yangshai etc. lakes on the lower reach of the Yangtze River was observed. The results indicated that: (1) During the developmental maturity stage, there are a Close correction between gonad development and liver change, the liver index gradually decreases and the gonad index gradually increases. (2) There were some regular differences between male and female crab in development of gonad, the gonad index and gonad-liver index of male crab which are is higher than those of female crab in August-September, but lower in October-November. (3) By histological and cytological observations, the development of gonad of male crab was earlier than that of female crab. (4) The occurrence of migration peak of crab is an external phenomenon of gonad cells having been matured. The liver index 7.5 could be suggested as the indicator to harvest the mitten crab of Yangtze population.