兽医产科学 第三章 受精

2.卵子在输卵管内的运行速度和维持受精能力的时间 2. Hours of oocyte keeping alive and preserving fertility in the oviduct

1）卵子在输卵管全程运行时间3-6天。

1）Time for oocyte to pass through oviduct is 3-6 days.

2）生化变化 biochemical changes
脂类变化：脂类成分和分布发生变化（磷脂、胆固醇）。
Changes of lipid: the component and distribution of lipid changed(phospholipid、cholesterol).
蛋白质变化：糖蛋白的结构和分布发生改变。 Changes of proteins: the structure and distribution of glycoprotein changed. 离子的变化：通过钠-钙泵的逆蠕动和钙-ATP酶的作用，使精 子胞内钙离子浓度增加。
pronucleus and fusion of both pronuclei.

受精的结果：使单倍体变成二倍体染色体，受精
卵发育成胚胎，种族得以延续。

Result of fertilization: the union of two
haploid gametes reconstitute a diploid cell , then the oosperm develops to be an embryo, so the stirps can be multiplyed.
第三章 受 精 Chapter 3 Fertilization
Main Points
Gametes’ Preparations for Fertilization Process of Fertilization

Introduction

受精：精卵结合并形成受精卵的过程。

Fertilization: the process of the fusion of gametes to
牛
绵羊
猪
马
兔
射精量(ml) 3-8 0.8-1 100-300 50-150 1 一次射精的精子总数(百万) 7000 3000 40000 10000 700 精子从射精部位运行到 受精部位的最快时间(min) 2-13 6 15-30 24 4-10 到达受精部位的精子数 ＜5000 600-700 1000 / 250-500

表2 公畜精子在母畜生殖道内存活时间与维持受精能力时间
牛 绵羊 猪 / 24 马 兔
动物种类 存活时间(h) 维持受精能力时间(h)
/ 48 28-50 30-36
144 43-50 72-120 30-32
（Ⅱ）卵子在输卵管内的运行 （Ⅱ）oocyte transport in oviduct
2）宫颈肌的收缩作用和精子的主动泳动
The muscle constrictions of cervix & the
motility of sperm
子宫和精液中的PGs可使子宫肌收缩；精子借助宫
颈黏液中的AA、糖等主动泳动。 PGs in cervix and seminal fluid can stimulate cervix constrictions; sperm can swim forward with the help of AA and glycose in
reconstitute an oosperm 受精的步骤：精卵相遇、识别与结合、精卵质膜融合、多 精子入卵阻滞、雄原核与雌原核发育和融合。


The Process of Fertilization: sperm-oocyte contact;
sperm-oocyte recognition and binding; spermoocyte membrane fusion; Preventing Polyspermy; the development of male pronucleus and female
（Ⅰ）精子在雌性生殖道内的运行
（Ⅰ）Sperm transport in the female reproductive tract
动物授精类型： 牛、羊属阴道授精型 猪、马属子宫授精型 Types of Insemination：
cattle and sheep inseminate the female in vagina
2）卵子在输卵管内维持受精能力的时间不超过24h（但犬6天）。
2）hours of oocyte preserving fertility is less than 24 hrs ( canine 6 days ).
二、精子在受精前的准备 Sperm Preparations for Fertilization
pig and horse inseminate the female in uterus
1.精子运行机理 Mechanism of Sperm Transport （1）精子在子宫颈内的运行
Sperm transport through cervix
1）酶系作用 Enzymatic work
精子通过子宫颈时,蛋白水解酶使宫颈黏蛋白分解,黏液变 稀薄,有利于精子运行。 When sperm’s passing by cervix, protease catalyze the degradation of cervical mucus protein. Cervical mucus becomes watery. This facilitates passage of sperm through the cervical canal.


（3）精子在输卵管内的运行
Sperm Transport through oviduct
1）峡部缩张 Isthmus constrictions 2）纤毛的摆动 ciliary lashing motion 3）壶峡部上方的回旋运动
circumnutation in upper Isthmus-Ampulla Junction
Changes of ions: with the working of Na+- Ca2+ pump and Ca2+-ATPase, the concentration of cytoplasmic Ca2+ increase
morphological & biochemical changes during sperm capacitation 1）形态学 morphological changes 出现超激活的鞭打动作，顶端膨大，顶体内外膜靠拢。 Hyperactive“Whiplash” motility，inflating of sperm head, acrosomal external and internal membrane getting closer.
（一）精子获能 sperm capacitation 精子在受精前在雌性生殖道内运行过程中发生进一步充分成熟的 变化，获得受精能力的过程。
During sperm transport in the female reproductive tract, sperm undergoes a series of maturational changes to achieve the ability to fertilize the egg, known collectively as capacitation. 1.获能时精子形态学和生化变化
3.精子在雌性生殖道内的存活时间与维持受精能力
的时间
Hours of sperm keeping alive and preserving
sperm fertility in the female reproductive
tract

表1 公畜射精量、精子总数和精子运行至受精部位的时间与精子数
动物种类
牛90h，绵羊72h，猪50h，马120h。其中从输卵管伞至壶腹部需5 （3.5-6）分钟,在壶峡联结部内滞留2天以上。
Cattle 90 hrs, Sheep 72 hrs, Swine 50 hrs, Horse120 hrs.
transfer from the fimbria to the ampulla needs 5 (3.5-6) min, remain 2 days in the Isthmus-Ampulla Junction.
第一节 配子在受精前的准备 SectionⅠ Gametes’ Preparations for Fertilization

Ⅰ、配子的运行
精卵结合部位：输卵管壶腹部
Ⅰ、The transport of gametes Site of fertilization: the ampulla of the oviduct

1.卵子运行机理 1. Mechanism of oocyte Transport 排卵后，COC进入壶腹部，停留2天。 After ovulation, COC ( cumulus-oocyte complex ) transfer into the ampulla, remain 2 days. 1）输卵管伞开张，并紧贴于卵巢表面，并在卵巢表面扫 动； The fimbria debut, cling to ovary surface, keep saccadic movement on the ovary surface.
4）精子的主动泳动 sperm motility 5）卵子释放趋化因子 chemotactic factor released by egg
2.精子运行速度、到达输卵管壶腹部时间和精子数 2. Rate of sperm transport、time and population
of substantial sperm arrival to the ampulla of
cervical mucus .
（2）精子在子宫体内的运行 Sperm Transport through uterine cavity

The transport of sperm through uterine cavity ionstrictions. 精液剌激→垂体激素分泌→ 雌激素、催产素、肾上腺 素→子宫肌收缩 Stimulation from seminal plasma →secretion of hypophyseal hormone →estrogen、oxytocin 、 adrenalin →uterine constrictions
oviduct
精子运行过程中，遇到的三个“栏筛” =“精子库” ： During the sperm transport, there are three “ barrier ”=“semen deposit” ：
1）子宫颈隐窝 cervical crypts 2）宫管结合部 uterotubal junction 3）输卵管峡部 Isthmus of oviduct
2）卵巢固有韧带收缩，使卵巢缓慢地以卵巢门为中轴向 左右翻动。 Ovary inherent ligamenta constriction, make the ovary turn slowly around the axis of the ostium. 3）输卵管活动（肌层、韧带、系膜收缩）。 Oviduct motion (muscular layer 、ligamenta 、 mesentery constriction ). 4）输卵管上皮的纤毛活动（E作用下）。 Ciliary motion of the oviductal epithelial cells. 5）输卵管上皮的分泌活动增加。 The secretory activity of the oviductal epithelial cells increase.