中国农业大学：《家畜繁殖学》课程教学资源（PPT课件）第五章 受精、妊娠与分娩（Fertilization, Gestation and Parturition）（6/6）

第二节早期胚胎发育、迁糁和附植 早期胚胎的发育 Development of Early embryos 妊娠识别 Maternal Recognition of Pregnancy 胚胎附植(着床) Implantation of Embryos 早期胚胎的迁移 Migration of Early Embryos

第二节 早期胚胎发育、迁移和附植 一、早期胚胎的发育 Development of Early Embryos 二、妊娠识别 Maternal Recognition of Pregnancy 三、胚胎附植（着床） Implantation of Embryos 早期胚胎的迁移 Migration of Early Embryos

早期胚胎的发育 )卵裂( Cleavage) 原核胚 2细胞胚胎 8细胞胚胎 (1 day-cow) 3 days-cow (14-16-0w) (3-4 days-sow

一、早期胚胎的发育 (一)卵裂 (Cleavage)

FIGURE 21 Scanning electron micrograph of uncompacted (left)and com their behavior. They suddenly huddle together, maximizing their con pacted (right)8-cell mouse em tact with the other blastomeres and forming a compact ball of cells bryo.(Photographs courtesy of C. Ziomek (Figure 21). This tightly packed arrangement is stabilized by tight junc tions that form between the outside cells of the ball, sealing off the inside of the sphere(Figure 22). The cells within the sphere form gap

Cleavage Cle ge Cleavage plane I C savage plane I p:aneⅡ plane IIA Cleavage p laneⅢB (A)ECHINODERM (Sea urchin) (B)MAMMAL (Rabbit)

(二)胚胎发育的阶段 1.桑椹胚( Morula) 2.囊胚( Blastocyst 3.原肠胚( Gastrulation of embryo) 细胞全能性( Totipotency of Cell Zona pellucida 稳 内细胞团 囊胚腔 卷 桑椹胚 囊胚 (4-7 days--cow (7-12 days--cow) (4-5 dassow) (5 days-sow) 内细胞团 滋养层 囊胚腔 囊胚的伸长 ( 14-16 days--cow)

(二)胚胎发育的阶段 1.桑椹胚 (Morula) 2.囊胚 (Blastocyst) 3. 原肠胚 (Gastrulation of Embryo) 细胞全能性(Totipotency of Cell)

Lorge Intercellular S EARLY 8 CELL → Tight Junctions and Microfilaments Gap junction MORULA Junctional Complex Microfilament BLASTOCOELI Desmosome BLASTOCYST

原核胚 2细胞胚胎 8细胞胚胎 (1 day--cow) (3 days--cow (14-16-s0w) (3-4 days-sow) Zona pellucida Q感内细胞团 囊胚腔 桑椹胚 囊胚 (4-7 days-cow (7-12 days-co (4-5 days-sow) 5 days-so 内细胞团 滋养层 囊胚腔 囊胚的伸长 (14-16 days-Cor

表1常见动物胚胎的发育进程和移行到子宫中的时间 参数 人 罗猴小鼠 大鼠 家兔马牛羊猪山 16-20 24 2细胞 36 24243831612.25 36 31 4细胞 384624-3638059526236 8-细胞51-6236-4850-6064-8732-4072 72 60 囊胚96 7482105-12068-76120-144168-192144-168120-144158 72909872.75140-14472-84662 46-48 98 进入子宫1296 的时间 进入子宫8-16细胞16·细胞桑椹胚桑椹胚囊胚囊胚816细胞8-16细胞46细胞1013细 胞 的阶段 13-18 附植时间813 (天) 妊娠期280150-1802021222330-3235-345278 145-1511461 (天) 备注排卵后排卵 卵后交配后交配后交配后排卵后排卵后 排卵后排卵后排卵后 (h) (h)(h )(h)

3. cleavage 2ce‖ 4-cell lucida nucleus 4. morula (n) 1st and 2nd polar bodies egg cell oviduct nucleus fertilization follicular cell implantation fimbriae oocyte ovulation blastocyst trophoblast Figure 51.10 Human development before implantation tructures and events proceed counterclockwise. At ovulation (1), the secondary oocyte leaves the ovary. A single sperm penetrates the zona pellucida, and fertilization (2)occurs in the oviduct. As the zygote moves along the oviduct, it undergoes cleavage (3)to produce a morula(4) The blastocyst forms(5, 6) and implants itself in the uterine lining(7)