静宁鸡胚脑发育的形态学观察

Morphological Development of Jingning Chicken Embryo Brain

静宁鸡胚胎孵化,从E8开始到出壳,每天随机取出5个鸡胚,甲醛固定,测量体重、头重和脑重,肉眼及体视镜观察鸡胚脑的形态特征,并取下小脑,石蜡包埋,连续切片,H.E.染色,光学显微镜观察、照相.结果：鸡胚的体重和头重随日龄而增加,E8~E12增重缓慢,从E13开始加速生长;而胚脑的增长与体重和头重的增长类似,即从E13开始生长快速.E13时,小脑皮质分成不明显的3层结构：薄层的内颗粒层,Purkinje细胞层和厚的外颗粒层,此时观察不到髓质;而到E16,外颗粒层变薄,Purkinje细胞层变厚,出现少量髓质;E20时小脑皮质分为明显的分子层、Purkinje细胞层和颗粒层,髓质有所增加.结论：静宁鸡胚胎脑的重量随胚胎体重的增重而增加,小脑髓质随着小脑皮质的发育而逐渐发生.

Fertilized eggs of Jingning chicken were hatched.Each day from E8 to E20,5 were selected randomly for study.All the eggs of different ages were opened and the embryos were taken out,body weight,head weight and brain weight were measured.Since E11,the brain was observed by the stereo microscope.The cerebellar was fixed with formaldehyde,paraffin-embedded,serial sliced,H.E.stained,at last studied by optical microscope.As the results：with the growth of chicken embryo,the body weight were gained slowly in E8-E12,and began fast-increasing since E13;The head weight and brain weight showed seem development tendency with body weight,also began the fast-increasing period from E13.Histological observation showed：the cerebellar cortex were laminated into 3 misty layers：thick external granule layer,very thin Purkinje cells layer and internal granule layer in E13 without cerebellar medullar,cerebellar medullar appeared in E16 with the external granule layer became thinner and increasing of the Purkinje cells.When in E20,the cerebellar cortex were clearly layered with thinner molecular layer,typical Purkinje cells layer and granule layer,the cerebellar medullar were increased.Conclusion：the development of chicken embryo brain weight were in the same tendency with the body weight,the structure of cerebellar were complete with the development of cerebellar cortex followed by cerebellar medullar developing.