《胚胎移植的应用》PPT课件.ppt

1、动物繁殖学双语教学English-Chinish of Reproductiong in Farm Animal,Trainingmanuai for embryo transfer in cattle,第二章 胚胎移植的应用 提高母畜的繁殖率 牛上应用胚胎移植技术的目的是提高母牛的繁殖率。,动物繁殖学双语教学,Applications of embryo transfer Chapter 2 INCREASE REPRODUCTION OF FEMALES The main use of embryo transfer in cattle has been to amplify (增强)re

2、productive rates of valuable females.,由于母牛的繁殖率低和世代间隔generation （世代）intervals,长胚胎移植技术特别适用于该物种。 generation intervals 世代间隔,动物繁殖学双语教学,Because of low reproductive rates and long generation （世代）intervals, embryo transfer is especially useful in this species.,牛的胚胎移植应用有许多价值，包括已经证实proven(证实)和没有被证实的scarcity(缺

3、乏), ，如遗传价值、抗病特性disease resistance（抗病）. 。 proven(证实) scarcity(缺乏), unique (独特的) disease resistance （抗病）,动物繁殖学双语教学,Cattle may be valuable for many remasons, including scarcity(缺乏), proven(证实) genetic value, or having unique (独特的)characteristics such as disease resistance（抗病）.,从理论上讲，胚胎移植在遗传和经济上 financi

4、al 都是安全的，例如 同时，simultaneously，乳和肉增长的同时也可获得投资investment 的好的回报。 Investment 投资 Financial 经济上 Simultaneously 同时 i.e. 例如,动物繁殖学双语教学,Investment（ 投资 ）embryo transfer is used to satisfy both genetic and financial(经济上) objectives simultaneously(同时), i.e. milk or meat production increase or greater efficiency,

5、 and the investment （投资）returns financial benefits as well.,采用胚胎移植技术可以将母牛的繁殖率提高10-5倍。 Tenfold 十倍 fivefold 5 倍,动物繁殖学双语教学,It is possible to increase reproductive rates of valuable cows by an average of tenfold(十倍) or more in a given year and fivefold （5倍）or more per lifetime with current embryo transf

6、er techniques.,采用卵子体外成熟培养这项新技术可以扩大和提高胚胎的利用率。 Amplification 扩大 in vitro 体外, Perfected 完成,动物繁殖学双语教学,This amplification(扩大) will increase substantially(充分地) as new technologies, such as maturing oocytes in vitro(体外), are perfected(完成).,选择适合的胚胎移植程序提高供体的繁殖率可以减低受体的费用 donors 供体 Routine 程序 Recipients 受体 Exp

7、ense 费用,动物繁殖学双语教学,Increased reproductive rates of donors (供体)with routine(程序) embryo transfer procedures are nearly always at the expense(费用) of reduced reproductive rates of recipients(受体).,这种方法仅用少数的供体体就可以与较多的受体结合. recipients受体 Conventionally 按常规,动物繁殖学双语教学,This means that fewer calves will be produ

8、ced from donors and recipients(受体) combined than if both reproduced conventionally(按常规).,因为受体必须要等待胚胎,但按常规受体不能妊娠。 recipients受体 to await等待 Pregnant 妊娠 conventionally 按常规,动物繁殖学双语教学,This is because potential recipients(受体) must be on hand to await(等待) embryos, which means recipients do not become pregna

9、nt(妊娠) as soon as they would conventionally (按常规).,为提高供体的繁殖率，可以采用合理的管理，将处理期间的损伤降到最小。 Minimized 减到最少 Justified 合理,动物繁殖学双语教学,This waiting can be minimized（减到最少）with good management, and is often justified(合理) by the increased reproductive rates of donors.,在胚胎移植中，对受体母牛移植2个半胚时，对移植的成功率会有影响。 exception例外 p

10、roportion比例 demi-embryos).半胚,动物繁殖学双语教学,An exception(例外) to decreased reproduction with embryo transfer can occur when a substantial proportion(比例) of recipients receive two embryos (or two demi-embryos).,在现行的胚胎移植中，极少采用双胎程序。 该技术可以扩大供体胚胎移植的繁殖率，详细内容参见第12章内容。 twinning 双胎 Amplification 扩大,动物繁殖学双语教学,Such

11、twinning （双胎）programmes, however, are currently a very minor use of embryo transfer. The degree of amplification(扩大) of reproduction of donors by embryo transfer will be considered in detail and in the context of other factors in Chapter 12.,需要告戒人们的是胚胎移植的真实情况，广告宣传惊人的成功率和最小的失败率。 有时，科学的实验结果较差，与公开出版的结果

12、不一致。 Caveat 告戒 Advertise 广告 Spectacular 惊人的,动物繁殖学双语教学,A caveat(告戒) is that people tend to advertise（广告） their spectacular（惊人的 ）successes and minimize their failures. There is even a bias in scientific reports because experiments with poor results tend not to be published.,因此，这种情况必须认真分析。 采用新的程序，成功率可能

13、特别低，而环境条件不利，实施好的管理，亦可获得好的结果。 Picture 画、局面 Hostile 不利的 Excellent 极好的.,动物繁殖学双语教学,Thus one must be careful to analyse the complete picture（画、局面）. Success rates can be especially poor in new programmes and in hostile(不利的) environments; with good management, they can also be excellent(极好的).,克服不孕 应用胚胎移植技术

14、可以从有遗传价值的母牛而这些母牛患有不孕疾病 CIRCUMVENT避免 FERTILITY 繁殖力 INFERTILITY不孕,动物繁殖学双语教学,CIRCUMVENT INFERTILITY It is possible to obtain offspring from genetically valuable cows that have become infertile due to injury(损伤), disease,或者年龄等原因，采用超数排卵和胚胎移植技术（ Bowen et al., 1978; Elsden et al., 1979）使用健康的、有繁殖力的供体，成功率可以达

15、到30%。 Superovulation 超数排卵 Achieved 达到 Fertile 有繁殖力的,动物繁殖学双语教学,or age by means of superovulation（超数排卵） and embryo transfer (Bowen et al., 1978; Elsden et al., 1979), although success rates are only about one-third of those achieved(达到) with healthy, fertile（有繁殖力的） donors.,未孕青年母牛和成年母牛通常不能不能繁殖。 Inferti

16、le 不孕 Subfertility 不孕 heifers 未生过小牛的小母牛 Propagated 繁殖.,动物繁殖学双语教学,Infertile heifers （未生过小牛的小母牛）and cows with genetically caused subfertility should not be propagated（繁殖）.,虽然成功率较低，但可以从从临死亡的母牛中获得卵母细胞，在试管内成熟培养，而后获得后代(Shea, 1978); ，在进行农场应用之前，此技术需要进行系统的优化实验。 Oocytes 卵母细胞 Moribund 垂死的 in vitro拉丁语 在试管内） Opt

17、imization 最优化的,动物繁殖学双语教学,Although success rates are low, it is possible to recover oocytes（卵母细胞） from genetically valuable, moribund(垂死的) cows, fertilize them in vitro（拉丁语 在试管内）, transfer them, and obtain offspring (Shea, 1978); techniques require only systematic optimization(最优化的) before they are a

18、pplied in the field.,不同的超排与回收程序与繁殖力状况列于表1。 Choice 选择 Recovery 回收,动物繁殖学双语教学,Choice （选择）of superovulatory and recovery（回收）procedures varies with the type of infertility (Table 1).,例如，有卵泡发育时，超排可以直接插人，也可以在撤除孕酮子宫内释放装置或注射PGF2a后进行 Cystic有胞囊 ovaries卵巢 regimen 支配 Insertion 插入 intravaginal device 子宫内释放装置 pros

19、taglandin F2 alpha. PGF2a,动物繁殖学双语教学,For example, cows with cystic(有胞囊) ovaries（卵巢） might be most effectively superovulated according to a regimen (支配)based on the insertion(插入) and removal of a progestin (孕酮)implant or intravaginal device (子宫内释放装置)rather than on injection of prostaglandin F2 alpha.,

20、出口与进口 为了改良牛群，增加牛群的基因库gene pool, 需要引进新的品种，以推动种群的出口与进口。importation/exportation IMPORT/EXPORT出口与进口 motivated推动,动物繁殖学双语教学,IMPORT/EXPORT（出口与进口） The desire to improve herds of cattle, to increase variation in the gene pool(基因库), and to introduce new breeds, has motivated(推动) the importation/exportation of

21、 breeding stock.,过去，贸易主要是以血统明确的pedigrees幼龄动物或精液为主。 Trade 贸易 pedigrees 血统明确的 semen. 精液,动物繁殖学双语教学,In the past, trade（贸易） has been primarily either in young animals with outstanding pedigrees (血统明确的)or semen.,选择的品种100%为新的基因型，可以很快影响到其群体。 Genotype 基因型 Impact 影响,动物繁殖学双语教学,Animals have the advantage of bei

22、ng 100 percent of the desired new genotype（基因型） and are usually of breeding age so that impact（影响） on the herd is immediate.,不利的isadvantages方面是成本，特别是运费isadvantages非常高，另外，在新环境，不同管理、气候会引发较高的发病率high morbidity(发病率) rate 或地方病endemic pathogens。 disadvantages不利的 transportation运费 morbidity发病率 rate, endemic

23、pathogens地方病.,动物繁殖学双语教学,The disadvantages(不利的) are that costs, especially for transportation（运费）, are very high, and that there is a high morbidity(发病率) rate if the new environment is markedly different in management, climate, or endemic pathogens(地方病).,但是，如果母牛是进口的，其基因型将影响到群体遗传基因，直到公牛犊达到育种年龄。 Import

24、ed 进口,动物繁殖学双语教学,Moreover, if cows are imported（进口）, the genetic influence on the general population is limited until their bull calves reach breeding age.,采用进口精液可以覆盖大的群体,后代中50%含有新的基因,但2-3年中不会出现新的个体.,动物繁殖学双语教学,While the genetic influence of imported semen can be distributed over a larger portion of t

25、he herd, offspring have only 50 percent of the new genes and will not become producing members of the herd for two to three years.,而应用进口imported胚胎,后代100%含有新的基因,采用人工授精artificial insemination,经过几年的操作,群体被扩大. Imported 进口 artificial insemination人工授精 Producers 生产者,制造者,动物繁殖学双语教学,With imported（进口 ）embryos,

26、the resulting offspring have 100 percent of the desired genes, but as with artificial insemination(人工授精), it will be several years until the resulting animals become producers(生产者).,精液与胚胎的优越与不利的比较列于表2.,动物繁殖学双语教学,The relative advantages(优越性)and disadvantages of importing animals, semen and embryos ar

27、e summarized in Table 2.,正确、严格的卫生标准涉及到品种和精液的贸易规则 Valid 正确的 serious 严肃的 Sanitary 卫生,动物繁殖学双语教学,Valid(正确的) and serious (严肃的)sanitary（卫生） and economic concerns have resulted in strict regulation of trade in breeding stock and semen (International Zoosanitary Code, 1986).,例如，为了防止传染病，犊牛和成年牛在进口前就必须进行一定时间的检

28、疫程序，精液也必须进行类似的检疫程序。 Quarantineand 检疫,动物繁殖学双语教学,For example, in order to prevent the introduction of infectious diseases, calves and adult cattle must often undergo a lengthy quarantineand(检疫 )testing programme before they may be imported; the collection and processing of semen is similarly regulated

29、.,进口的条件非常宽，而检疫的范围也需要从数月至数年，也需要与销售方协定。,动物繁殖学双语教学,Conditions of importation vary widely and frequently require months to years to carry out, many of them in advance of a proposed sales agreement.,因此，胚胎移植相关服务的费用是昂贵和烦杂的。 Logistics 后方勤务 Complicated 麻烦的 Costly 昂贵的,动物繁殖学双语教学,Thus, logistics（后方勤务）are quite

30、complicated（麻烦的）and costly（昂贵的）.,一些传染性微生物infectious organisms可以通过胚胎移植程序传播(Hare, 1986), 结果不仅可造成流产abortion ，而且造成胎儿会畸形abnormalities（King et al., 1985). infectious organisms传染性微生物 Abnormalities 畸形、变态,动物繁殖学双语教学,Few infectious organisms（传染性微生物） are spread by routine embryo transfer procedures (Hare, 1986)

31、, and such procedures do not result in rates of abortion （流产）or incidence of abnormalities（畸形、变态） among offspring that diffcr from those of the normal population of cattle (King et al., 1985).,胚胎的一些结构，如透明带zona pellucida，具有防御protection 特征，它可以限制circumscribcd 环境和体状况对胚胎的影响。 Protection 防御 zona pellucida

32、透明带 minute 精密的 circumscribcd 限制 host 宿主,动物繁殖学双语教学,Such characteristics of embryos as protection（防御）by the zona pellucida（透明带）, minute （精密的）size, exposure only to a very circumscribcd （限制）environment, and lack of body systems to host（宿主）,动物繁殖学双语教学,pathogens病原体 (e.g. respiratory呼吸, digestive消化, circul

33、atory循环 systems) result in significant barriers to infection传染屏障.,另外，对胚胎的冲洗处理，也是一种安全保护处理。 Wash 冲洗, Treat 处理 safeguards保护,动物繁殖学双语教学,In addition, it is possible to wash（冲洗）, treat（处理）, and physically examine the individual embryo, which provides additional, very effective safeguards（保护）.,因此，胚胎是对动物基因物质

34、的一种安全的保护方式 (Stringfellow, 1985; Hare and Seidel, 1987). Innately 天生的 post-natal 死后偿还,动物繁殖学双语教学,Thus, importation of genetic material in the form of embryos is innately（天生的） safer than importation of post-natal （死后偿还）animals or semen (Stringfellow, 1985; Hare and Seidel, 1987).,按规章制度承认和起草的进口文件与章程比较现实

35、。 Regulatory officials按规章制度 drafting起草 time-consuming 耗时的 post-natal 死后偿还,动物繁殖学双语教学,Regulatory officials（按规章制度） recognize this fact and are drafting（起草 ）realistic conditions for importation that are less time-consuming （耗时的）than those required for post-natal animals.,卫生规则附注还包括采集精液、生产胚胎、预期出口的计划等。 Per

36、taining 附属 Intended 预期的 Export 出口,动物繁殖学双语教学,Health regulations pertaining（附属）to the collection and processing of the semen used to produce embryos intended（预期的） for export（出口）, however, may still apply.,在诸多情况下，采用胚胎移植技术进口品种降低了卫生的风险。,动物繁殖学双语教学,The decreased risk of compromising the health of national

37、herds in itself makes embryo transfer the method of choice for importing breeding stock in many cases.,其他的优点是后代将可以获得100%的期望基因型，从受体recipient中获得被动免疫passive immunity而适合于新环境。 immunity被动免疫 recipient受体,动物繁殖学双语教学,Other advantages are that the offspring will be 100 percent of the desired genotype and will a

38、dapt more readily to the new environment because of passive immunity（被动免疫 ）acquired from the recipient（受体）.,在新的环境体系中，这些问题是存在的。例如在北美的高产奶牛产体系中，奶牛在粗放extensive的管理系统中，采用饲草饲喂foraging Unthriftiness 浪费的 Inappropriate 不适当 Extensive 粗放的 Foraging 饲草,动物繁殖学双语教学,There is still a potential for problems of unthrift

39、iness（浪费的） and disappointing（令人失望 ）production if the type of cow is inappropriate（不适当） for the new environment, as for example, a high-producing North American dairy cow would be for an extensive（粗放的）management system based on range foraging（饲草）.,胚胎进口的成本通常比活畜要低，一个品种的世代在一个群体内变化。 generation（世代）.,动物繁殖学

40、双语教学,Costs of importing embryos are often lower than importing post-natal animals, and it is possible to change the breed of a herd within a single generation（世代）.,然而，其成本比进口精液要高，胚胎移植作为一种遗传改良的程序比传统的人工授精artificial insemination应用要少，但它比较精确 intensive。 Intensive 精确,动物繁殖学双语教学,Nevertheless, costs are still

41、a great deal higher than importing semen, and conventional embryo transfer remains a less potent tool for genetic progress than artificial insemination（人工授精） programmes based on intensive（精确） selection.,MOET程序 MOET, Nicholas and Smith (1983) ，超数排卵与胚胎移植，与牛遗传改良最优化相关的胚胎移植技术。,动物繁殖学双语教学,MOET PROGRAMMES T

42、he term MOET, multiple ovulation and embryo transfer was coined by Nicholas and Smith (1983) to consider embryo transfer and related technology in the context of optimizing genctic improvement of cattle.,多数MOET 程序需要一个或少数几个大型核心群。通过胚胎移植、人工授精、或更多使用核心群年轻公牛扩大优秀基因。 Disseminated 播(种)、散布,动物繁殖学双语教学,Most MOET

43、 schemes require one or a few large nucleus herds. The resulting genetic improvement would be disseminated（散布 ）to the general population by embryo transfer, artificial insemination, or more practically by young bulls to be used in natural breeding.,MOET与先进的技术相关，不 适合inappropriate在发展中国家实施。 inappropria

44、te 不适合,动物繁殖学双语教学,MOET procedures rely on advanced technology, which at first seems inappropriate （不适合）for less developed countries.,但是,这些技术可能carded在在一个或几个实施,也可在一些不发达的国家应用. carded 可能,动物繁殖学双语教学,However, nearly all of the advanced technical procedures would be carded (可能)out at one or a few central sit

45、es, which may be especially appropriate for some applications in many less developed countries.,叙述MOET程序后,我们将讨论MOET 的理论与实践问题.,动物繁殖学双语教学,There are both practical and theoretical advantages to MOET, which will be discussed after a description of MOET procedures.,在评价 Appreciate MOET程序问什么有效益之前,首先必须简要的考虑

46、动物育种的程序. Appreciate 评价,动物繁殖学双语教学,To appreciate(评价) why MOET procedures are effective, it is necessary to consider briefly conventional animal breeding procedures.,在实践中,动物改良做法有: 鉴定动物的遗传价值,这样才能使用和把最好的母体 Parents留到下一世代. Improved 改良 Identify 把鉴定 Parents 母体，亲本,动物繁殖学双语教学,Improved (改良)animals result from th

47、e following practices. Identify (把鉴定)genetically valuable animals accurately so that the best can be used as parents(母体，亲本) of the next generation.,可以进行生产性能测定 、performance testing后裔测定progeny testing、和 血统分析 pedigree analysis performance testing性能测定 progeny testing后裔测定 pedigree analysis血统分析,动物繁殖学双语教学,

48、This can be done by performance testing(性能测定), progeny testing(后裔测定) and pedigree analysis(血统分析).,生产性能测定 Performance testing 可以由动物本身测定，例如生长率，产乳性能和犊牛等级（作为犊牛的特性或母牛的特性）,动物繁殖学双语教学,Performance testing measures the animal itself, e.g. rate and efficiency of growth, milk production or the degree of calving

49、 difficulty (as a trait of the calf or the mother).,因为一些遗传特性与生产性能有关，所以必须进行特殊的测定才能获得。,动物繁殖学双语教学,Because there is some genetic component to such performance, a partial measure of genetic value is obtained.,在对群体进行生产性能测定时，要考虑低成本、快速、可利用的原则。,动物繁殖学双语教学,Advantages of performance testing include low cost, ra

50、pid availability of data and ability to test many or all of the animals in the population.,低准确性的（诸多情况下每个动物只测定一个项目）、环境因素（某些情况对动物的操纵是预先准备的）、性别限制，例如公牛不能进行乳产量性能的测试等 Disadvantages 不利 confusion 混乱 Deliberate 有准备的,动物繁殖学双语教学,Disadvantages（不利） are low accuracy (in many cases one measurement per animal), conf

51、usion （混乱）by environmental factors (in some cases deliberate（有准备的 ）manipulation in order to make certain animals look good) and sex limitations, e.g. one cannot performance test a bull for milk production.,后裔测定Progeny testing 是对改良后代性能的测定，它与生产性能测定是相反的performance testing Converse 逆(转)的,动物繁殖学双语教学,Proge

52、ny testing measures traits in offspring of animals and in many respects is the converse逆(转)的 of performance testing.,这里没有性别的限制，超越了不同的环境的影响， Misleading 误解的,动物繁殖学双语教学,It is not sex limited and can be done over a variety of environments in ways that are not likely to be misleading（误解的）.,在这里，直到下一世代，昂贵的e

53、xpensive的资料才能被利用，只有选择动物的数量才能才可能进行后裔测定。 Expensive 昂贵的,动物繁殖学双语教学,However, it is （昂贵的）, data are not available until the next generation and only limited numbers of animals can be progeny tested.,准确的后裔测定在牛上是困难的，因为受到后裔数量的限制。许多情况下，生产性能测定之前先进行后裔测定。,动物繁殖学双语教学,Accurate progeny testing is difficult with cows

54、 because of limited numbers of offspring. In many cases a performance test is used to pre-select animals for progeny testing.,应用血统分析Pedigree可以母系或同胞遗传基因值siblings Pedigree 血统 Siblings 同胞,动物繁殖学双语教学,Pedigree（血统）analysis simply uses information available example, the genetic value of parents or siblings（

55、同胞）.,采用高选择强度 选择遗传性能最好母牛。 选择优秀的母牛可以进行繁殖传播propagated Propagated 繁殖传播,动物繁殖学双语教学,Use high selection intensity（强度） so that only the best animals genetically are selected as parents. Genetically superior cattle are propagated（繁殖传播） selectively,在这个自然育种体系中，采用人工授精、胚胎移植、仅采用最好的母牛和少数最好的公牛。,动物繁殖学双语教学,by artifici

56、al insemination and embryo transfer, by keeping offspring from only the best cows and by using only the few best bulls in natural breeding systems.,由于母牛的繁殖率较低，所以大多数遗传程序选择公牛是从众多的后裔中挑选。,动物繁殖学双语教学,Because of low reproductive rates of cows, most genetic progress is made by selecting bulls and obtaining

57、many progeny per bull.,最小的世代间隔 假如选择的每一阶为3年，2个间隔将为6年。,动物繁殖学双语教学,Minimize the generation interval. If selection steps can be made every three years, genetic progress will be nearly twice what it would be with selection every six years.,后裔测定的时间与世代的间隔有关，它还影响到下一个世代，并影响到改良的进度。 Dissipates 浪费,动物繁殖学双语教学,Prog

58、eny testing lengthens the generation interval because data are not available until the next generation, which often dissipates（浪费） the advantages of the increased accuracy.,MOET在生产性能测试和血统分析的基础上真实的选择了品种的优秀品质，与后裔测定相比，减少了世代间隔。 Objective 真实 Pedigree 血统,动物繁殖学双语教学,The main objective（真实）of MOET is to selec

59、t on the basis of performance tests and pedigree（血统） analysis in order to reduce the generation interval, in comparison to progeny testing procedures used currently.,采用胚胎移植和超数排卵亦加强了母牛的选择强度。 intensity 强度 Superovulation 超数排卵,动物繁殖学双语教学,Selection intensity （强度）is increased on the female side with superovulation （超数排卵） and embryo transfer.,在MOET 中，如胚胎被分隔，估计遗传值将增加。因为这样可以产生2个相同基因型的个体。 slightly 略 Split 分离 Assessments 估计,动物繁殖学双语教学,In MOET schemes, genetic progress increases slightly （略）if embryos are split（分离 ）so that more accurate assessments（估计） of