幼畜胚胎体外生产技术的研究进展

家畜JIVET技术采用外源促性腺激素处理幼龄母畜,诱导其卵泡大量发育,并与活体采卵、卵母细胞体外成熟、体外受精技术相结合体外生产胚胎,经胚胎移植后产生后代。本文综述了JIVET技术的研究现状,以及JIVET技术中幼畜的选择、超排方案、卵母细胞采集和体外培养的条件等,并进一步分析了JIVET技术生产胚胎的影响因素及存在的问题。     

幼畜胚胎体外生产技术的研究进展

家畜JIVET技术采用外源促性腺激素处理幼龄母畜,诱导其卵泡大量发育,并与活体采卵、卵母细胞体外成熟、体外受精技术相结合体外生产胚胎,经胚胎移植后产生后代.本文综述了JIVET技术的研究现状,以及JIVET技术中幼畜的选择、超排方案、卵母细胞采集和体外培养的条件等,并进一步分析了JIVET技术生产胚胎的影响因素及存在的问题.     

幼畜超数排卵及卵母细胞体外成熟的研究进展

利用幼畜进行超数排卵,产生数量远高于成年母畜生产的窦状卵泡,结合活体取卵、卵母细胞体外成熟和体外受精等技术,大量生产体外胚胎,并移植至成年代孕母畜子宫内,迅速获得众多后代个体的系统工程,被称为幼畜体外胚胎移植技术(Juvenile in Vitro Embryo Transfer, JIVET)。该技术能最大程度地缩短世代间隔,加速遗传选育进度,可为胚胎干细胞、动物克隆和转基因动物制备等研究提供丰富的胚胎试验材料。JIVET技术成败的关键在于幼畜的超数排卵和体外成熟环节。该文综述了幼畜超数排卵的生理基础、幼畜的超数排卵效果;同时从卵泡液微环境、卵丘细胞状态、卵母细胞的细胞质和细胞核成熟以及体外成熟的优化方案等方面介绍了幼畜卵母细胞体外成熟的研究进展。     

幼畜胚胎体外生产技术研究进展

家畜JIVET技术采用外源促性腺激素处理幼龄母畜,诱导其卵泡大量发育,并与活体采卵、卵母细胞体外成熟、体外受精技术相结合体外生产胚胎,经胚胎移植后产生后代。本文综述了JIVET技术的研究现状、基本操作步骤,并进一步分析了JIVET技术中的影响因素,以及该技术所存在的问题和发展前景。     

羔羊卵母细胞体外生产胚胎技术研究进展

就幼龄动物与成年动物卵母细胞在细胞形态、代谢和发育能力方面的差异，以及羔羊卵母细胞发育的影响因素等进行了综述。不断改进羔羊激素诱导卵泡超数发育方案，改善JIVET技术的效率，将会致使这项技术走向商业化。     

羔羊超数排卵与胚胎体外生产技术研究进展

自从幼畜体外胚胎移植(JIVET)技术问世以来,因其在优秀种畜快繁、育种世代间隔缩短、遗传资源保护等方面具有广阔的应用前景,引起了很多科研机构的关注.为提高JIVET的生产效率,研究人员对该技术的多个环节进行了探索,但总体效率还不是很高.论文就羔羊超数排卵与胚胎体外生产技术实施中的关键环节,即羔羊超排供体的年龄、超排季...     

羔羊超数排卵及体外胚胎生产技术的研究与应用进展

幼畜超数排卵及体外胚胎生产技术(JIVET)技术,是集幼畜超排、活体采卵、卵母细胞体外成熟、体外受精、胚胎体外培养和移植等技术为一体的新型生物技术体系。因其能快繁优秀种畜、缩短育种世代间隔、保护遗传资源等优点具有广阔的应用前景。本文综述了羔羊JIVET技术的原理、基本操作步骤和研究现状,分析了羔羊应用JIVET技术效果、影响因素、存在的问题和发展前景。     

牛羊幼畜胚胎体外生产技术的研究进展

幼畜胚胎体外生产技术(Juvenile in vitro embryo technology,简称JIVET)是集幼畜超排、活体采卵、卵母细胞体外成熟及受精、胚胎移植等技术为一体的胚胎生物技术体系,可以极大程度地缩短世代间隔,为胚胎生产及研究优良种畜提供技术指导。本文综述了JIVET的研究现状、操作流程,并进一步分析了JIVET中的影响因素,以及该技术目前所存在的问题和发展前景,为更好的生产应用提供一定的借鉴。     

牛羊繁育提速技术在京成功 绵羊繁育效率比常规胚胎移植提高20倍

从澳大利亚引进的新一代牛羊快速繁育技术-牛羊幼畜超排技术(JIVET技术),在北京创新科农农牧科技有限公司香河基地试验成功。这一技术将大大加速我国牛羊育种进程和优良种畜的扩繁。JIVET技术是集羔羊的超数排卵、卵母细胞体外成熟、体外受精、胚胎体外培养和胚胎移植等技     

幼畜胚胎体外生产技术研究进展

幼畜超排是根据性成熟前幼畜（1~2月龄）卵巢对生殖激素敏感,卵泡发育很少发生闭锁的特殊生理特点而发明的一项高效率生产卵母细胞的新技术。该技术是集幼畜超排、体外受精、胚胎移植等技术为一体的胚胎生物技术体系。作者从幼畜超排、体外受精和胚胎移植等方面阐述了目前幼畜体外胚胎生产技术的现状及发展前景。     

Developmental Capabilities of Embryos Produced In Vitro from Prepubertal Lamb Oocytes

Breeding from prepubertal females, known as juvenile in vitro embryo transfer (JIVET), reduces the generation interval and increases the rate of genetic gain in animal breeding programs. While the birth of the first lambs from prepubertal ewes occurred nearly 30 years ago; and there is considerable interest in the commercialization of this technology, its efficiency remains too low. The advent of in vitro production (IVP) of embryo resulted in the more widespread use of JIVET. Morphologic and metabolic differences coupled with reduced in vitro and in vivo development of oocytes derived from prepubertal animals have been reported. Research has been undertaken to optimize donor selection and hormone stimulation methods in an attempt to reduce the variability and increase the proportion of donors responding to hormone stimulation and increase oocyte developmental competence. Yet, this variation persists and the development of oocytes and embryos from prepubertal animals remains reduced when compared with adults. Recent improvements to JIVET, resulting from a modified hormone stimulation regime, have eliminated the failure of donors to respond to hormone stimulation, and increased both the number and developmental competence of oocytes harvested from very young prepubertal lambs. This increased efficiency has facilitated the incorporation of other reproductive technologies such as sperm sexing with JIVET, resulting in the birth of lambs of a pre-determined sex from prepubertal lambs. Increased rates of genetic gain in sheep breeding programs can be achieved by combining sexed sperm with oocytes obtained from lambs as young as 3–4 weeks of age. Continued increases in the efficiency of JIVET resulting from further improvements to hormone stimulation regimes and an increased understanding of the differences between oocytes from adult and prepubertal animals will result in the commercialization of this technology.     

幼羔胚胎体外生产技术研究进展

幼羔胚胎体外生产技术(JIVET)是全球草食类动物繁殖技术中最先进的生物工程技术。国内外对幼羔经激素诱导后生产胚胎已作了许多研究,并取得一定的成果,本文就其研究进展作一综述。     

利用JIVET技术快速繁育萨福克羊的研究

JIVET技术是一项利用生殖激素刺激幼畜卵巢,从而使其快速、高效生产卵母细胞的技术。对4只1月龄萨福克幼羔注射FSH和PMSG激素,48 h后采用手术法抽取幼羔卵母细胞,并在体外成熟;将成熟的卵母细胞与精子进行体外受精,将正常分裂的2~8细胞胚胎移植到6只同期发情的受体小尾寒羊子宫内。结果显示,采用激素法处理萨福克幼羔后共采集到可用卵母细胞109枚,体外成熟培养后得到成熟卵母细胞79枚,成熟率为72.48%;体外受精后得到正常卵裂胚胎34枚,卵裂率为43.04%;胚胎移植后有3只受体母羊怀孕,受胎率为50%,并分娩得到3只萨福克幼羔。综上提示,利用JIVET技术可以缩短萨福克羊的繁育周期,从而加快其繁育速度。     

高寒牧区无角陶赛特羊胚胎移植试验及其后裔的生长发育指标测定

在环青海湖地区的共和县引进澳大利亚无角陶赛特羊胚胎,以当地青海半细毛羊为受体,进行胚胎移植,结果移植冻胚60枚,产羔28只,移植妊娠率为46.67%,羔羊成活率为100%。羔羊生长发育指标测定结果表明,胚胎移植羔羊平均出生重3.25kg,4月龄前生长发育最为迅速,平均日增重达205.96g,6月龄平均体重32.47kg。     

肉羊胚胎移植和经济杂交技术在海北州养羊业中的应用

以海北州畜牧兽医科学研究所现有陶赛特种羊和良种繁殖场为依托 ,以胚胎移植技术为核心 ,高效廉价扩繁陶赛特种羊数量 ,以藏羊为受体冻胚移植 63只 ,产羔 3 0只 ,移植妊娠率 47.62 % ,繁殖成活率 10 0 %。同时以经济杂交技术在本地区开发羔肉羊高效生产 ,取得了良好的经济杂交效果。经测定 :人工授精受胎率达 94.87% ,产羔成活率 90 %以上 ,繁殖成活率 80 %以上。陶×藏一代羔羊 4月龄宰前活重 2 7.14kg ,4月龄羯羔胴体重 12 .5 2kg ,屠宰率 46.14 % ,净肉率74.3 6% ,显著高于当地羔羊。通过引进陶赛特绵羊 ,利用杂交优势 ,实行肉羊高效生产技术开发 ,特别进行羔羊生产具有明显的杂交优势 ,在高寒牧区可以推广应用。     

Optimizing female allocation to reproductive technologies considering merit,inbreeding and cost in nucleus breeding programmes with genomic selection

Female reproductive technologies such as multiple ovulation and embryo transfer (MOET) and juvenile in vitro fertilization and embryo transfer (JIVET) have been shown to accelerate genetic gain by increasing selection intensity and decreasing generation interval. Genomic selection (GS) increases the accuracy of selection of young candidates which can further accelerate genetic gain. Optimal contribution selection (OCS) is an effective method of keeping the rate of inbreeding at a sustainable level while increasing genetic merit. OCS could also be used to selectively and optimally allocate reproductive technologies in mate selection while accounting for their cost. This study uses stochastic simulation to simulate breeding programmes that use a combination of artificial insemination (AI) or natural mating (N), MOET and JIVET with GS. OCS was used to restrict inbreeding to 1.0% increase per generation and also to optimize use of reproductive technologies, considering their effect on genetic gain as well as their cost. Two Australian sheep breeding objectives were used as an example to illustrate the methodology—a terminal sire breeding objective (A) and a dual‐purpose self‐replacing breeding objective (B). The objective function used for optimization considered genetic merit, constrained inbreeding and cost of technologies where costs were offset by a premium paid to the seedstock breeder investing in female reproductive technologies. The premium was based on the cumulative discounted expression of genetic merit in the progeny of a commercial tier in the breeding programme multiplied by the proportion of that benefit received by the breeder. With breeding objective B, the highest premium of 64% paid to the breeder resulted in the highest allocation of reproductive technologies (4%–10% for MOET and 19%–54% for JIVET) and hence the highest annual genetic gain. Conversely, breeding objective A, which had a lower dollar value of the breeding objective and a maximum of 5% mating types for JIVET and zero for MOET were optimal, even when highest premiums were paid. This study highlights that the level of investment in breeding technologies to accelerate genetic gain depends on the investment of genetic improvement returned to the breeder per index point gain achieved. It also demonstrates that breeding programmes can be optimized including allocation of reproductive technologies at the individual animal level. Accounting for revenue to the breeder and cost of the technologies can facilitate more practical decision support for beef and sheep breeders.     

绵羊胚胎移植技术在柴达木地区的应用

2006年在青海省海西州德令哈市洋嘉生态农业开发有限公司进行了绵羊胚胎移植试验,试验中同期发情和超数排卵处理青海高原毛肉兼用半细毛羊共86只,同期发情率达88.37%,其中将超排效果好的11只羊做为胚胎移植受体羊,同时处理供体羊特克赛尔羊7只。试验结果:11只受体羊平均超数排卵点2.8个/只,7只供体羊平均超数排卵11.9枚,取卵9.7枚,卵子受精率17.65%,移植12枚胚胎,其中1只受体羊移植双胚,最后观察到移植的11只受体羊中妊娠5只,产羔5只(移双胚的羊产1只羊羔),移植受胎率达45.45%,羔羊成活率达100%。     

高原地区肉羊胚胎移植试验

2003年在青海省东部农业区和环湖牧区开展了以特克赛尔、萨福克和无角陶赛特为主要品种的肉羊胚胎移植试验。对农区55只小尾寒羊受体和牧区76只半细毛羊受体进行了同期发情处理,小尾寒羊同期发情率为81.28%,半细毛羊为63.16%。半细毛羊移植胚胎44枚,产羔13只,流产1只(双羔),移植受胎率为31.82%;每只小尾寒羊移植2枚胚胎,共移植20只受体40枚胚胎,产羔5只,其中1只母羊产双羔,受胎率为12.50%。所产18只羔羊全部成活。