【作者】 侯庆文；

【导师】 黄永宏；

【作者基本信息】 扬州大学 ， 动物遗传育种与繁殖， 2002， 硕士

【摘要】 本实验以海门山羊为材，对山羊胚胎胚层的发生、早期胚胎形态、泌尿生殖器官的发生及胚胎生长发育规律等方面进行了系统研究。主要结果如下： 1．海门山羊胚胎的胚层主要发生在10天8小时～18天8小时(10d8h～18d8h)，胚胎从球状囊逐渐转变成管状囊，这一伸长过程实际是滋养层伸长的结果。10d8h的胚胎，内细胞团从形态上开始出现了明显变化，内细胞团内侧细胞明显脱离内细胞团进入囊胚腔，形成了最早的内胚层细胞；胚胎12d8h，内细胞团完全裸露于胚泡表面，内细胞团细胞迅速增生形成胚盘，并向外周扩散而围成原肠腔；中胚层来自外胚层，由原条区分离产生的特化的中胚层细胞形成；中胚层产生以后，滋养层细胞由单层扁平变成单层柱状；18d8h的胚胎建立起了中轴器官，体节4对，体节中有肌腔，此时神经管愈合，羊膜结产生。 2．早期胚胎的胎膜由绒毛膜、尿囊、羊膜和卵黄囊组成，绒毛叶阜在29d14h产生。20d8h～27d14h的胚胎属鳃弓期，胚胎头、颈、背均弯曲；心和肝的原基均形成隆突，且心隆突起初大于肝隆突，但肝隆突发育加快，在25d14h超过了心隆突；前后肢芽依次发生，由丘状逐渐变成桨状；尾芽于24d8h清晰可见；脑部发育基本完成；消化系统、循环系统生长较快，各器官原基已产生。29～37d的胚胎属于指蹼期，面部发育已有明显进展，外观鳃裂已愈合；前后肢芽尖端变为指状，指间有蹼膜，后肢芽长度超过前肢芽；心隆突几乎完全消失；生殖结节产生。42d的胚胎属于偶蹄期，面部出现雏形，种的特征已表现出来，外观可辩雌雄；颈、背曲伸直，头和躯干比例明显变小；肢部分节，形成偶蹄。 3．海门山羊胚胎泌尿器官的发生，重演了系统的进化过程，从前肾、中肾到后肾。前肾出现的时间很短，很快分化成中肾；22d胚胎的中肾呈香蕉状，随胚胎日龄的增加逐渐向胚体尾端推移;胚胎29d时，后肾呈椭圆形。 山羊早期胚胎的生殖器官由中肾管、生殖腺、米勒氏管、尿殖窦及生殖结节分化而成。胚胎24d时，中肾腹内侧出现了生殖蜡;27d胚胎，生殖晴中部膨大演变成生殖腺，生殖腺呈长梭形，突向体腔;胚胎29d时，生殖腺己发生性别分化，生殖腺与中肾分离，生殖腺髓质内有原始精小管。 4.海门山羊胚胎在鳃弓期至偶蹄期阶段的生长模式，按缓慢一快速一缓慢一快速的循环往返进行，共有4个快速生长期，分别为22d一25d、27d一33d、35d一37d和39d一47d。更多还原

【Abstract】 This research used Hai Men Goats as materias. Four aspects were investigated and the main results were summarized as follows:1. During E10d8h-18d8h (Which means embryo development time from 10 days and 8 hours to 18 days and 8 hours after coitus), the germ layer of Hai Men Goats embryo occured. The embryo changed ball-shaped bursa into tube-shaped bursa. In fact the process of elongation was the coclusion of the elongation of the trophoblast. At E18d8h, the shape of the inner cell mass took place obvious change. The cells that located on the inner side of the inner cell mass separated from the inner cell mass obviously and entered the blastocoel. These cells formed the endoderm. At E12d8h, the inner cell mass was exposed in the surface of the blastocyst entirely. The hyperplasia of the inner cell mass formed the germinal disc. The endoderblast diffused outside and envolped archenteron. The mesoderm came from ectoderm. The mesodermblast separated from the primitive steak. After the mesodermblast formation the trophoblast changed from flat cells to cubic cells. At E18d8h, the axis apparatus erected. The embryo had four paires of somites. The somites had a hole. The neural tube was healed. The amnia kot was produced.2. The caul of the early embryo was made up of chorion, allantois, amnia and the chorion .The chorion cotyledon was produced at E29d14h- From 20d to 27d after coitus, the goat embry was in the stage of branchial arch. The head, neck and back all bent. The heart and liver projected, the projection of the heart was bigger than that of the liver. Because the projection of the liver developed fast, it was bigger than that of the liver at E25d14h.The hinder limb bud was produced, following the front limb bud. The limb budschanged their mound-shaped into pulp bord-shaped gradually. The tail bud was seen clearly at E24d8h. The morphology of the brain had formed basically. The digestive system and the circulatory system developed fast. All the organ’ s buds had genesised. The stage of thumb web was 29-37d after coitus. The development of the face made great progress. The branchial crack has been healed. The limb-top was figner-shaped and there was a membrance between fingers. The later limb bud was longer than the front limb bud. The heart disappeared projection nearly. The genital projection appeared. The 42d embryo was in the artiodactyla stage. The face appeared rudiment and the charcteristic of the bread has manifested. The male and female embryo can be distinguished. The mamary buds were produced and the limb was node-shaped.3. The goat embryo re-acted the process of the system evolution, which passed through pronephros, mesonephros and metanephros. The pronephros exsisted shortly and transformed into the mesonephros rapidly. At E22d, the mesonephros became bannaner-shaped. The mesonephros processed towards the tail with days increasing. At E29d the metanephros appeared renal.The genital organ of the early goat embryo was mad up of mesonephric duct, gonad, Mulerian duct, urogenital sinus and genital tubercle. At E24d, the genital crest emerged on the inner side of the mesonephros. At E29d, the gonad had occured sex differentiation. The gonad separated from the mesonephros. The primary seminiferous tubule existed in the medulla.4.The growth of the embryo process in term of slowness-speediness-slowness -speediness circularly during E22d-47d. The goat embryo had 4 fast growth periods (22d-25d, 27d-33d, 35d-37d and 39d-47d).更多还原