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红安格斯与高非良种肉牛胚胎移植技术 总被引：1，自引：0，他引：1
牛胚胎移植技术 ,是家畜繁殖领域的一次技术突破。为探讨本地黄牛对加拿大红安格斯、高非牛胚胎移植的适应性、胚胎移植成活率、产仔成活率及加拿大肉牛生产性能 ,本课题组进行了一系列实验研究 ,经过两年来的研究和工作 ,为进行国外良种肉牛胚胎移植积累了一定的实验数据和经验。1 实验材料1.1 良种肉牛胚胎的选择及引进 从加拿大畜牧服务公司引进加拿大高非肉牛胚胎 2 0枚 ,红安格斯肉牛胚胎 5 0枚。1.2 受体牛的选择 在对本地黄牛进行普查的基础上 ,选择体型较大、健康、无生殖道疾病、3岁以上、经产的本地母牛 83头 ,在我市黄山镇… 相似文献
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目前,我国本地黄牛改良亟需大批优良种畜或良种胚胎.因此,引进国外良种肉牛胚胎,应用该技术建立新的品种改良体系,加大品种改良力度,是畜牧业生产发展的需要.安徽省畜禽品种改良站在1996年引进20枚夏洛来牛冷冻胚胎,两次进行胚胎移植,于1997年7月产下7头夏洛来牛. 相似文献
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二十世纪未，我国畜牧科学工作者针对我国良种肉牛品种少、分布不均的具体状况，设计了通过引进良种公牛、冻精以及胚胎移植方法，改善我国肉牛品种质量和分布结构。其中，胚胎移植法不失为一种节省资金、效果显著的方法。 我们于１９９７－１９９８年在吉林省农业科学院奶牛场和通榆县三家子种牛场进行了胚胎移植试验研究，共解冻胚胎４３枚，试验供体牛４０头，取得较满意的成果，报告如下。 １ 胚胎来源 １９９７年春，从内蒙古呼和浩特家畜繁殖改良站购进进口加拿大肉用品种胚胎２００枚，并冷冻保存于吉林省农科院冷冻精液室。 ２ 受体… 相似文献
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引进加拿大利木赞、夏洛来良种肉牛冷冻胚胎，借本地牛之腹移植生产种牛，再从中选育生产性能较高的个体进行超排采胚和生产胚胎，这是目前在畜牧生产中应用胚胎移植技术加快，良种繁育的有效途径之一。1998—2001年在宁夏家畜改良站，从1997年冻胚移植产下的胚胎牛中，选出30头利木赞和9头夏洛来牛作供体，进行超排试验。现将超排结果分析总结如下。 相似文献
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互助县利用良种肉牛细管冻精与本地黄牛进行杂交改良,已取得了显著的经济效益,但是引进大型肉牛品种皮埃蒙特牛改良本地黄牛尚属首次,为了探讨皮埃蒙特牛与本地黄牛的杂交效果,互助县自2002年起引进该品种牛细管冻精,利用人工授精技术在互助县双树乡、威远镇、台子乡、五峰乡进 相似文献
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利用进口加系肉用型西门塔尔优秀后代和美加系优秀种公牛冻精生产胚胎,改良本地肉牛,有利于高效地利用引进种质,加快我国肉牛品种改良的速度。目的:本文评估实施胚胎生产过程中,供体母牛在放牧中导致焦虫病,对胚胎生产结果及冻胚移植成功率影响。方法:本文选择40头10-16月龄加系西门塔尔种母牛进行超数排卵处理生产体内胚胎。在超排处理过程,其中17头放牧的供体牛出现焦虫病症状。对照组为24头舍饲健康供体牛。两组牛产的胚胎冷冻后,分别解冻和移植了30(焦虫病组)和26(对照组)枚胚胎。结果表明两组牛只获取的胚胎总数差异不明显,但发病牛只生产可用胚率和冻胚移植成活率均明显低于健康牛只。结论:焦虫病极易导致牛只体温升高,超过39.5℃将会严重影响胚胎的产量和质量。 相似文献
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生产条件下山羊胚胎移植的组织实施与质量控制 总被引：7，自引：0，他引：7
从我国国情出发，系统论述了生产下山羊胚胎移植的组织实施步骤及质量控制因素。提出了生产条件下山羊胚胎移植的主要质量控制指标：选择适宜的供、受体、并加强饲养管理；用ＦＳＨ３００￣３５０ＩＵ以减量法进行供体超排；用孕激素阴道海绵栓配合促性腺激素进行受体同期发情；鲜胚移植采用从供体子宫角手术的回收的桑椹胚￣囊胚期胚胎，胚冻冷冻或胚胎分割采用囊胚期胚胎，并移植于受体羊子宫角，完整的记录体系。 相似文献
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应用冷冻胚胎移植,可以不受时间,地域和供受体牛发情同期化处理等条件的限制,能更大地发挥胚胎移植技术的实用价值并提高经济效益。八七年四月,广东省农科院畜牧研究所采用美国阿姆狄斯畜牧技术有限公司提供的高产奶牛和良种肉牛冷冻胚胎进行移植。八八年元月产犊完毕,现将冻胚 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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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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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
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 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