鸡胚鳃器官的扫描电镜观察

Development of branchial apparatus in chick embryos-Scanning electron microscopic observations

用显微解剖术和扫描电镜方法观察第11～21期鸡胚鳃器官的形态结构．鸡胚鳃器官由4对鳃弓、鳃沟、鳃膜和咽囊组成。第11期第1对鳃弓出现于心隆起颅侧。此后，第2—4对鳃弓分别出现在心隆起两侧。相邻鳃弓之间隔以相应的鳃沟，鳃沟与咽囊之间的薄层组织为鳃膜。在原始咽内部，咽囊最初呈圆弧形小坑状，继而加深变窄呈沟缝状。第17期第1、2对咽囊借鳃裂与鳃沟相通。

The morphogenesis of the branchial apparatus was examined by scanning electron microscopy in chick embryos from stages 11 to 21. In chick embryos, there are 4 pairs of branchial arches, branchial grooves, branchial membranes and pharyngeal pouches, which are designated as branchial apparatus. At stage 11 the 1st arches appear as two slight adjacent protrusions cranial to the heart bulge in the ventral middle part. Until stage 17 the four pairs of branchial arches appear successively. Each arch is clearly demarcated from the neighboring ones by a shallow branchial groove. The region of the ectodermal brancial grooves corresponds to the entodermal outpocketings of the foregut-pharyngeal pouches,which at early stage look like a shallow pit, then deepen into a groove. The pharyngeal pouches are separated from the corresponding branchial grooves by branchial membrane. The right and left halves of the visceral arches are separated by the heart bulge except the 1st arches which are adjacent to each other.