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猪的胚胎移植是指将一头母猪的早期胚胎取出,移植到另一头生理状态相同的母猪生殖道内．使之发育成为新个体的技术．又称之为“人工受胎”或“借腹怀胎”。提供胚胎的个体称为供体,接受胚胎的个体称为受体。一头刚刚出生的母猪卵巢上有数以万计的卵母细胞,但终其一生能发育成熟、排卵、 相似文献
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胚胎移植也称受精卵移植或简称卵移植。它的含义是将1头良种母畜配种后的早期胚胎取出，移植到另一头同种的生理状态相同的母畜体内，使之继续发育成为新个体，所以也有人通俗地叫“人工受胎”或“借腹怀胎”。提供胚胎的个体称为供体，接受胚胎的个体称为受体。 相似文献
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动物的胚胎移植及其在畜牧生产中的应用 总被引：1，自引：0，他引：1
胚胎移植(embryotransfer,ET)是指从一头(只)雌性动物的生殖道(输卵管或子宫)内取出早期胚胎,或者是通过体外受精、胚胎分割、克隆等方法获得胚胎,然后把这些胚胎移植到另外一些雌性动物生殖道的相应部位,使其着床、发育,最后产下后代。即俗称的“借腹怀胎”。在胚胎移植中,把提供胚胎的动物称为供体(donor),接受胚胎移植的则称为受体(recipient)。一般而言,供体为优良品种或优秀个体,或者是特定的畜种或个体,而受体为生产性能较差的品种或个体,以达到“借一般动物之腹怀优良品种或优秀个体之胎”的目的,从而增加良种后代的数量,迅速提高畜… 相似文献
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郑成利 《河南畜牧兽医(综合版)》2008,29(7)
胚胎移植是指将动物的早期胚胎从其体内取出,移植到另一头同种并且生理状态相同的雌性动物体内,使之继续妊娠发育为新个体的过程。供给胚胎的母畜通常称为供体,接受和孕育胚胎的母畜称为受体。牛胚胎移植 相似文献
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牛胚胎移植技术在我国养牛业中的应用及前景 总被引：10，自引：0，他引：10
动物胚胎移植 (ｅｍｂｒｙｏｔｒａｎｓｆｅｒ,ＥＴ)是将一头优秀母畜配种后的早期胚胎用手术或非手术的方法取出 ,移植到另一头同种并且生理状态相同的母畜体内 ,使之继续妊娠发育为新个体的技术 ,所以也称为借腹怀胎或人工授卵。为了使供体母畜多排卵 ,通常要用促性腺激素处理 ,促使几个、十几个甚至更多的卵泡发育并排卵 ,因此国外将常规的胚胎移植常称为ＭＯＥＴ (ＭｕｌｔｉｐｌｅＯｖｕｌａｔｉｏｎａｎｄＥｍｂｒｙｏＴｒａｎｓ ｆｅｒ) ,即超数排卵胚胎移植或称为多排卵胚胎移植。目前科学技术的发展 ,用体外生产胚胎 (ＩＶＰ ,ｉｎ… 相似文献
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胚胎移植又称受精卵移植 ,是从一头母畜 (称为“供体”)的生殖器官里取出附植前的受精卵 (又称为“胚胎”) ,直接或经冷冻保存再解冻后移植到另外一头与供体同时发情排卵但未经配种的母畜 (又称为“受体”)的相应部位 ,使这个外来的胚胎在受体的子宫着床 ,并继续生长和发育 ,最后产下供体的后代 ,即“借腹怀胎”。牛的胚胎移植是选择遗传品质优良、体质健壮结实、体型优美具有高产能力的母牛 (供体 ) ,使用人工措施使之超数排卵 ,经受精后 ,将胚胎取出借用其他母牛 (受体 )的子宫 ,同时生出供体的多个犊牛的方法。牛的胚胎移植具有极为重要… 相似文献
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马鹿胚胎移植是一项新的人工繁殖技术,也称为借腹怀胎。这种方法是将新形成而未着床的早期胚胎从一头母鹿体内取出植入另一头母鹿的生殖道内,使其正常发育直至分娩。供给胚胎的母鹿称供体母鹿;接受和孕育胚胎的母鹿称为受体母鹿。经胚胎移植出生的后代的基因是从供体母鹿和与供体母鹿交配的公鹿那里获得的。采用胚胎移植技术对提高优质种母鹿繁殖力具有重要作用。1供体母鹿的超数排卵选择个体较大、后代生产力较高、膘情在八成以上,年龄为4～7周岁的健康母鹿做为供体母鹿。根据马鹿季节性繁殖的特点,试验均在每年的秋季开始。在繁殖季节的任… 相似文献
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郑成利 《河南畜牧兽医(综合版)》2008,29(7):24-25
胚胎移植是指将动物的早期胚胎从其体内取出．移植到另一头同种并且生理状态相同的雌性动物体内．使之继续妊娠发育为新个体的过程。供给胚胎的母畜通常称为供体，接受和孕育胚胎的母畜称为受体。牛胚胎移植是一项动物细胞工程的实用技术．这项技术对提高牛优良品种的繁殖能力以及加速品种改良具有明显的优势。在生产实践条件下，牛移植胚胎的受孕率平均为65％，接近人工授精的受孕率，冷冻胚胎受孕率也可达到50％以上。 相似文献
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阎明毅 《青海畜牧兽医杂志》2007,37(6):37-38
家畜胚胎移植技术是将一头优秀母畜配种后的早期胚胎用手术或非手术方法取出，移植到另一头同种并且生理状态相同的母畜体内，使之继续妊娠发育成新个体的技术，所以也叫借腹怀胎。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献