短盖巨脂鲤消化系统胚后发育学的研究

Studies on the Development of Digestive System of the White Achama

应用显微与超微技术 ,对短盖巨脂鲤消化系统胚后发育的组织形态学做了研究 ,以探讨其消化吸收机理 ,并为深入研究短盖巨脂鲤的营养学和病理学提供某些资料。短盖巨脂鲤初孵仔鱼消化道仅是一段位于卵黄囊背后方的实心细胞索。短盖巨脂鲤消化系统的胚后发育、形成和完善 ,需经过 3个功能阶段。第 1个阶段 (0～ 3日龄 ) ,消化道几乎未分化 ;第 2个阶段 (4～ 15日龄 ) ,消化系统初步发育成型 ,具备单纯的基本结构 ,具一定的摄食、储存、消化和吸收生理功能 ;第 3阶段 (16～ 5 0日龄 ) ,形成胃腺和幽门盲囊 ,消化系统发育完善 ,具备成鱼的结构。

The development of digestive system of the white achama(Piaractus brachypomum,Cuvier)were studied using light and electron microscopy in this paper,in order to discuss the mechanism of digestion and assimilation,and provide some information to lucubrate nutriology and pathology of the white achama.After hatching,the digestive tract is only a simple closed tube above the posterior segment of yolk sac.The development,formation and completement of digestive system expierences three functional stages.Digestive tract hardly diffrentiates in the first stage (0～3 days after hatching).Basic structure of digestive system developes,the digestive tract become functional and can take up,store,digest and assimilate food in the second stage (4～15 days after hatching). In the third stage (16～50 days after hatching),digestive system almost developes completely,gastric glands and pyloric caeces have formed.The development of digestive system relates to the growth stages of the larvale closely.