细鳞鱼的卵黄发生

Vitellogenesis in Brachymystax lenok

从发育生物学—卵黄发生角度,通过光镜和透射电镜对细鳞鱼(Brachymystax lenok)卵黄发生进行观察。结果表明,细鳞鱼的卵黄发生主要集中在初级卵母细胞阶段完成,可分为4个特征时期:初级生长期,皮质泡期,卵黄积累期,卵黄积累完成期。当卵母细胞进入初级生长早期,卵子发生特征物——类核周体出现;进入皮质泡期,其主要特征是皮质泡、卵黄外膜和巴尔比亚尼体结构;处于卵黄积累期,位于其外周细胞质附近会出现卵黄颗粒;进入卵黄积累完成期,卵黄颗粒不断融合增大,占据细胞绝大部分。以上结果为细鳞鱼的卵巢发育分期提供了理论基础,并深入探讨其发育的规律性、特殊性和复杂性,从而指导细鳞鱼的人工繁殖、选育种工作及野生群体的资源保护和合理利用。

Brachyrnystax lenok is a valuable fish of cold water in China. Because of population growth, biological resources over-exploitation, environmental pollution and so on, their habitats and living ambiance have been threatened. Now the distribution areas of B. lenok has decreased gradually in China, and population quantity falls off gradually. Therefore, the research on phylogenetic development and breeding of B. lenok appears especially important. And some scholars at home and abroad have made a great quantity of research on the structure and change of egg membrane, vitellogenesis, follicle cells and atresia folliculi during primary oocyte development process of teleostei, and has mainly discussed oocyte function and mechanism of action in the course of the vitellogenesis, and characteristic change and fundamental function of corpora atretica etc. But there is not the research about the aspect of B. lenok. From the developmental biology point of view, this paper focuses on the vitellogenesis of B. lenok by the light and transmission electron microscope. The results indicate that the vitellogenesis is concentrated mainly on primary oocyte phase, and might be divided into four phases： primary growth phase of oocyte; cortical vesicle phase; vitelline accumulation phase and complete phase of vitelline accumulation. When the oocyte enters into the primary growth phase, the character substance of oogenesis （for short Nuage） occurs. At the cortical vesicle phase, it is the central character that there are the cortical vesicle, vitelline ectoblast and Balbiani＇ s body. At the vitelline accumulation phase, the vitelline granule appears near the cytoplasm. When the oocyte enters into the complete phase of vitelline accumulation, the vitelline granules are fused and augmented continuously, and occupied most cell space. The results provide theoretical reference for the development stage of ovaries in B. lenok, and the regularity, particularity and complexity of ovaries development have been investigated, thereby rational instruction has been provided for the artificial propagation and selection and breeding of B. lenok, and resource protection and reasonable utilization of wild population. [Journal of Fishery Sciences of China,2007, 14（3） ：377 - 382]