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本研究旨在对西藏小型猪Cytb基因序列和氨基酸序列进行分析,研究其遗传分化及其与欧洲品种猪和中国几个地方猪种的亲缘关系。结果表明,西藏小型猪Cytb基因序列有9个变异位点,核苷酸多样性为0.0789。中国猪种包括西藏小型猪的Cytb基因序列与欧洲品种猪相比有16个主要突变位点,其中西藏小型猪有2个特殊碱基突变位点:420位点的T→C转换和883位点的G→A转换,几乎各占50%。氨基酸序列分析表明,西藏小型猪与欧洲品种猪有3个氨基酸位点存在着差异,其中在295位点,一部分西藏小型猪与以上其它几个品种猪同为缬氨酸(V),而另一部分西藏小型猪为异亮氨酸(I)。结果显示只有部分西藏小型猪与巴马小型猪、贵州香猪、五指山猪有很近的亲缘关系,同时证实西藏小型猪群体内存在遗传分化。 相似文献
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作者介绍了国内外猪内源性反转录病毒（PERV）研究进展,简述了中国不同品种小型猪PERV存在情况、PERV前病毒全基因克隆与序列分析、细胞水平鉴定方法、感染HEK293细胞研究平台的创建、猪A3F对PERV的抑制作用研究,以及从分子遗传学上揭示不同品系PERV特异性等创新性研究成果,分析了五指山小型猪近交系具有PERV基因拷贝少且没有PERV-C等特异性,以及展望培育中国PERV阴性猪新品系方法等研究,以期为人类异种器官移植和生物医用材料产品安全性研发,解决小型猪PERV疾病传播危险性提供科学对策和新的方向。 相似文献
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本研究对荣昌猪和内江猪的TYR基因外显子1进行了克隆测序及序列分析，结果发现3个新的突变位点：319C→T，537C的插入，551A→G。部分突变序列已被GenBank收录，登录号为：AY236997。将突变序列翻译成氨基酸序列后发现，319C→T和551A→G是同义交变。537C的插入是移码突变，其是否会对猪的毛色造成影响，还有待进一步研究。 相似文献
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利用RT—PCR和RACE方法克隆了正常猪和全同胞多趾猪Lmbr1基因部分cDNA序列并进行了序列分析。结果表明,正常猪该序列长1797bp,其中CDS序列1178bp,3’UTR序列619bp。全同胞多趾猪该序列长1069bp,其中CDS序列768bp,3’UTR序列301bp。正常猪与多趾猪Lmbr1基因的CDS序列相似性近77％,而3’UTR序列相似性不足20％。两者的CDS序列在755～768bp间,共发生13个核苷酸突变：G755C、A756T、A757G、T758C、C759A、A760G、C761T、T762G、A763C、G764T、A765G、T767G、T768A。其中,前11个突变属于错义突变,导致相应的氨基酸序列中4个氨基酸发生变化：G突变为A、I突变为A、T突变为V、R突变为L;后2个突变属于无义突变,导致阅读框提前终止。猪Lmbrl基因发生突变能引起SHH的异常表达,这可能是导致猪多趾发生的根本原因。 相似文献
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为获得五指山猪FUT1基因序列并分析其基因结构,检测FUT1基因中的单核苷酸多态性(SNP)位点在五指山猪群体中的分布情况,本试验利用PCR扩增猪FUT1基因组序列,通过基因测序寻找该基因中的SNP位点,使用PCR-RFLP方法对120头五指山猪进行了FUT1基因型检测,并运用生物信息学方法对FUT1基因序列进行分析。在猪FUT1基因组中共发现两个单碱基突变,分别位于编码区(A+307G)和3'非翻译区(A+1856C);在FUT1基因A+307G突变位点上,五指山猪均为GG基因型;此外,FUT1基因启动子区域和第2外显子处存在CpG岛。本研究成功获得五指山猪FUT1基因序列信息,为下一步五指山猪FUT1基因的功能研究奠定基础。 相似文献
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为了研究合作猪γ-IFN基因的多态性,确定其等位基因数、核苷酸多态位点,各等位基因是否符合Hardy-Weinberg平衡状态、多态信息含量、有效等位基因数和杂合度,采用PCR-SSCP方法检测了138头合作猪γ-IFN基因外显子4的等位基因,并克隆、测序群体内变异产生的各等位基因序列,就基因型和等位基因单倍型序列数据开展分析。序列比对分析发现5个核苷酸多态位点,其中5 284 bp(A→G)、5 341 bp(G→A)、5 371 bp(A→G)为新发现突变位点。试验群体发现4种基因型AA、AB、AC和AD,其中A等位基因频率为0.963 8,为优势等位基因。经χ2适合性检验,该群体处于Hardy-Weinberg平衡状态(P>0.05)。γ-IFN基因遗传多态指数中,杂合度(He)、多态信息含量(PIC)、有效等位基因数(Ne)均较低,表明合作猪γ-IFN基因比较保守。 相似文献
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利用CDNA末端快速扩增技术（RACE）成功扩增了广西巴马小型猪近交系连续4代次及封闭群的猪内源性反转录病毒（PERV）3UTR,共获得8条序列（GenBank登录号分别为：GQ475493、GQ475494、GQ475495、GQ475496、GQ475497、GQ475498、GQ475499、GQ475500）,分为638、749bp 2种不同的类型,都属于PERV-A亚型。以PERV-3UTR构建遗传进化树,PERV-A,B,C分群清晰,3UTR可作为PERV亚型区分的另一基因序列。对调控元件定位分析,推测具有749bp类型3UTR的PERV病毒转录水平更高。在所获得序列的209～227bp位置,发现了＂CTTGAAACTT＂10个碱基的1.9个重复。模拟RNA二级结构,广西巴马小型猪PERV-3UTR 2种类型无论从空间构型、自由能,还是茎环数量都存在明显的不同。这些结果为全面评价广西巴马小型猪来源的PERV病原安全性提供了参考。 相似文献
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Nramp1是学术界近年研究的猪重要抗病基因之一,其第6内含子作为Nramp1的分型重点片段,国内外的诸多猪种均有清晰的测序分析结果。本研究通过提取浦东白猪血液组织DNA,使用PCR技术分离和克隆Nramp1基因的第6内含子基因片段,测序后与以往文献中的其他猪种进行比较。结果发现,浦东白猪在该段基因中有3个特异的突变点普遍存在,分别是259 bp的A→G突变,331 bp的G→A突变和29 bp后1~2个T碱基的插入。这些突变的发现可以为浦东白猪的育种和Nramp1的抗病性研究提供遗传数据。 相似文献
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不同猪种TGFβ-RⅠ基因单核苷酸多态性分析 总被引：3，自引：2，他引：1
研究通过对猪TGFβ-RⅠ基因多态性与产仔数的关系的分析,寻找与猪产仔数相关的分子遗传标记,以期加快猪育种进程。本研究以大白猪和长白猪(共计329头)为实验材料,采用PCR-SSCP技术,共设计5对引物,对猪TGFβ-RⅠ基因的第7内含子的全序列进行多态性分析,发现2个多态性位点。经测序分析,在引物1的56bp处和引物4的148bp处均发现突变,分别为G→T和A→G。同时在不同猪群,利用最小二乘法对这2个突变位点的基因型进行组合构成的基因型与产仔数的相关性进行分析。结果表明:在大白猪中,2胎及以上的总产仔数(TNB)的AACC基因型组合显著高于AACD和ABCD(P<0.05);在所有胎次的TNB的AACC基因型组合显著高于ABCD(P<0.05),也高于AACD。 相似文献
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采用PCR-SSCP和PCR-RFLP技术分析了类胰岛素生长因子1(IGF-Ⅰ)基因5′侧翼区、第5外显子、第2外显子在南阳牛、鲁西牛、中国西门塔尔牛3个牛品种中的遗传多态.结果表明在IGF-Ⅰ基因的5′侧翼区、第5外显子上未发现PCR-SSCP或PCR-RFLP遗传多态;在第2外显子中发现PCR-SSCP多态,有3种基因型AA型、AB型、BB型.对第2外显子的多态片段测序分析表明在35 bp处有碱基A→G的突变,248 bp处有碱基C→T的突变,256 bp处有碱基A→G的突变;35 bp、248 bp的碱基突变都是无义突变,而256 bp处碱基A→G的突变为有义突变,使谷氨酸变为甘氨酸. 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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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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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献