蒙古绵羊胚胎胃的组织发生

Histogenesis of Mongolia Sheep Embryonic Stomach

运用组织学方法研究了蒙古绵羊胚胎胃的组织发生,主要对5-550mm胚胎胃的组织结构及主要组织结构的发育规律进行了研究.结果如下:5mm胚胃芽呈梭形膨大;胚胎发育到70mm胃的外形同成体的基本一致;5mm胚胃壁由复层上皮和多层胚性结缔组织细胞构成;8mm胚胃上皮为单层柱状上皮,其下为大量的胚性结缔组织;30mm时瘤胃和网胃上皮均为复层扁平上皮,瓣胃和真胃上皮仍为单层柱状上皮,胃腺开始发育;90mm胚网胃皱襞开始形成;164mm胚真胃胃小凹底部形成强嗜碱性细胞群;195 mm胚瘤胃瘤状突开始发育,真胃出现壁细胞;252 mm胚网胃出现平滑肌带;290 mm胚真胃腺体可分辨出壁细胞、主细胞、颈黏液细胞;335 mm胚网胃黏膜肌可见并进入皱襞;550 mm胚网胃平滑肌带清晰可见,网状皱襞及其乳突从外形上开始形成.

Using the normal method of histology,the histogenesis of embryonic stomach was studied.The histological structure and some main tissue structure development of stomach belong to 5-550mm embryo were observed.The result shows： the stomach of 5mm embryo which swells is spindle-shaped and the conformation of stomach of 70mm embryo corresponds to the adults on the whole.Stomach wall of 5mm embryo is made up of stratified epithelium and multilayer embryonic connective tissue.The epithelium of stomach of 8mm embryo is simple columnar,under which there is a great deal of embryonic connective tissue.The epithelia of the rumen and the reticulum of 30mm embryo are all stratified pavement epithelium,and the epithelium of the omasum and abomasum are still simple columnar epithelium.At this time,the gastric gland starts to develop.The gastric mucosa of the reticulum of 90mm embryo has a little tubercle and the reticulate lyra starts to form.There are strong alkalophilic cell groups at the bottom of the gastric pit of abomasum of 164mm embryo.The tuberculiform tubercle of rumen starts to develop and the parietal cells show up in abomasum of 195mm embryo.The smooth muscle belt appears in the reticulum of 252mm embryo.Parietal cell,chief cell and mucous neck cell can be identified from the gland of abomasum of 290mm embryo.The lamina muscularis mucosae of reticulum can be seen in 335mm embryo and enter the lyra.The smooth muscle belt of reticulum of 550mm embryo can be seen clearly,the conformation of reticulate lyra and its mamillary process start to show up.