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10个绵羊品种的微卫星DNA多态性研究 总被引：9，自引：1，他引：8
本研究利用FAO和ILRI推荐的21个微卫星引物,结合荧光标记PCR,检测了中国9个地方绵羊（Ovisaries）品种和1个外来绵羊品种的遗传多样性。21个微卫星座位均呈现出高度多态,多态性信息含量和杂合度均表明我国地方绵羊品种有着丰富的遗传多样性。本研究共检测到342个等位基因,有效等位基因数在2．1752～9．4997之间,座位平均杂合度在0．5248～0．8551之间,品种平均杂合度在0．633-0．761之间。聚类关系和主成分分析结果与其起源、育成历史及地理分布基本一致。 相似文献
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：用8个微卫星标记对闽南黄牛的等位基因频率、多态信息含量、杂合度和有效等位基因数等指标进行统计分析,并在此基础上对其进行聚类分析和分类研究。结果：8个微卫星标记在所检测的闽南黄牛群体中都表现出较丰富的多态性,在4个群体8个微卫星座位共有58个等位基因,每个微卫星标记平均检测到7．2个等位基因（3～11）;8个微卫星标记的平均多态信息含量（PIC）为0．6471,各群体的平均多态信息含量（PIC）差并不显著;全部群体平均杂合度为0．2930;各群体平均有效等位基因数为3．37。此表明闽南黄牛在微卫星位点上具有丰富的遗传多样性;根据奈氏标准遗传距离进行UPGMA聚类分析,结果表明4个群体间的遗传变异不大。 相似文献
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兰州大尾羊微卫星DNA多态性研究 总被引：1，自引：0，他引：1
研究旨在分析兰州大尾羊的微卫星DNA多态性,以期了解该品种的遗传多样性,为该品种保种选育和品质的进一步提高提供资料。选择15对微卫星引物,通过计算基因频率、多态性信息含量、有效等位基因数和杂合度,评估其品种内的遗传变异。结果表明:在15个座位中,共检测到153个等位基因,每个座位平均为10.2个等位基因;座位平均杂合度为0.8149;平均有效等位基因数为6.0891;平均多态性信息含量为0.7762。结果提示,兰州大尾羊群体存在丰富的遗传多样性,所选微卫星标记可用于绵羊遗传多样性评估。 相似文献
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蒙古马4个地方品种SSR遗传多样性的研究 总被引：1，自引：0，他引：1
利用个策卫星基因座对蒙古马勒个地方品种的188匹马进行了遗传检测。通过软件计算了各微卫星座位的有效等位基因数（E）、多态信息含量（PIC）、平均杂合度（H），并构建NJ聚类图和UPGMA聚类图。结果：9个微卫星基因座均为高度多态位点；4个群体在个位点上的平均有效等位基因数为5.0570-6.0744，平均PIC为0.7662，4个群体平均杂合度无显著差异，均很高；乌珠穆沁马群体与乌审马群体遗传分化最近，马尔虎马群体与锡尼河马群体遗传分化较远。 相似文献
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利用微卫星DNA多态性预测引进肉用绵羊品种杂种优势 总被引：4，自引：2，他引：2
旨在利用微卫星DNA在不同绵羊群体中的多态性预测引进肉用绵羊品种与地方绵羊品种的杂种优势。利用23个微卫星基因座对4个国外引进肉羊品种及3个地方绵羊品种的群体多态信息含量、有效等位基因数、杂合度和遗传距离进行遗传检测,并测定引进肉羊与地方肉羊品种的杂交效果。结果,23个微卫星座位在7个绵羊群体中均呈现高度多态,共检测到348个等位基因,平均每个座位等位基因数为15个;多态信息含量在0.532 1~0.936 1,有效等位基因数在2.572 8~9.345 8,平均杂合度在0.549 2~0.936 0,品种平均杂合度在0.714 2~0.829 5,可以用于绵羊遗传多样性的评估。从不同品种看,无角陶赛特的遗传变异最大,而小尾寒羊的遗传变异相对较小;经遗传关系分析,在引进的4个肉羊品种中,与小尾寒羊、蒙古羊及滩羊杂交优势由大到小依次为白萨福克、波德代、无角陶赛特、特克赛尔,与实际杂种优势测定结果一致。利用微卫星DNA多态性预测引进肉用绵羊品种与小尾寒羊、蒙古羊及滩羊的杂种优势是可行的,这将对今后绵羊育种具有重要的应用价值和指导意义。 相似文献
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利用微卫星标记技术,选用16个微卫星位点对60只闽西南黑兔群体遗传多态性和遗传结构进行分析。结果表明,在所检测的闽西南黑兔群体中,16个微卫星位点共检测到了75个等位基因,各位点的等位基因数在3～7之间,平均等位基因数为4.688个,平均有效等位基因数为3.443。各位点平均基因频率取样方差V（pij）为5.7546×10-3。16个微卫星位点平均观察杂合度HO为0.764,范围在0.200～1.000之间,平均期望杂合度He 0.685,其范围在0.410～0.811之间,各位点多态信息含量（PIC）变动范围为0.359～0.776,平均PIC为0.629,其中有13个位点处于高度多态（PIC〉0.5）,16个微卫星位点的平均固定指数（F）为-0.115。在所检测的16个微卫星位点上,经x2平衡检验,闽西南黑兔群体偏离Hardy～Weinberg程度不大。 相似文献
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云南大河猪保种群的微卫星检测 总被引：3，自引：1，他引：2
作者采用世界粮农组织（FAO）和国际动物遗传学会（ISAG)联合推荐的27对微卫星DNA引物中的20对引物,检测了云南大河猪保种群的83个个体的基因型。通过计算等位基因频率、遗传杂合度（H）、多态信息含量(PIC)、有效等位基因数,从而分析大河猪保种群的遗传多样性。结果表明,大河猪保种群在20个微卫星座位上拥有的等位基因较为丰富,20个微卫星座位上共有137个等位基因,平均6.85个,群体有效等位基因数共104个,平均5.2个;大河猪保种群的遗传多样性较为丰富,杂合度为0.792,多态信息含量为0.765。 相似文献
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8个微卫星座位在海北金银滩藏羊群体中的多态性分析 总被引：1，自引：0，他引：1
研究旨在分析金银滩藏羊的微卫星DNA多态性,以期了解该品种的遗传多样性,为该品种的保种选育和品质的进一步提高提供有益资料。利用8对微卫星引物,以金银滩藏羊为研究对象,通过计算基因频率、多态性信息含量、有效等位基因数和杂合度,评估其品种内的遗传变异。结果表明：在8个微卫星座位中,共检测到83个等位基因,每个座位平均10.38个等位基因;平均杂合度0.893;平均有效等位基因数9.06;平均多态性信息含量0.871。结果提示,金银滩藏羊群体存在丰富的遗传多样性,所选微卫星标记可用于绵羊遗传多样性评估。 相似文献
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5个山羊品种的遗传结构及多样性研究 总被引：1，自引：0，他引：1
用25个微卫星标记,对5个山羊品种进行遗传多样性分析。共检测到199个等位基因,并进行哈代-温伯格平衡检验,5个群体基本处于遗传不平衡状态。在25个座位中,除BMS1943在罕山白绒山羊上（PIC为0.493）表现为中度多态外,其余座位均为高度多态。以等位基因为基础,得出座位的平均杂合度为0.436-0.820之间,群体平均杂合度在0.592-0.738。对各微卫星标记进行F-统计分析,Fst的变化范围是从BMC1206的0.011到BMS1943的0.078;群体每代迁移数在2.972-23.115,平均值为8.884。计算了遗传分化系数,结果表明群体间变异程度不高。内蒙的罕山白绒山羊和乌珠穆沁绒山羊有较大的基因流值（15.753）,说明其交流比较活跃。计算了共祖遗传距离,并进行了UPGMA和NJ聚类分析,内蒙的罕山白绒山羊和乌珠穆沁绒山羊聚到一起。 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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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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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