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根据GenBank中猪Ⅱ型圆环病毒(PCV-2)基因序列,设计两对特异性引物.将PCV-2广东分离株(GD1株)用PK15细胞系培养,从细胞培养物中提取病毒总DNA并以之为模板,用PCR方法分段扩增病毒全基因组,分别克隆到pMD18-T载体,对阳性质粒进行序列测定.用DNAstar对序列进行拼接,得到PCV-2 GD1株基因组全序列,全长为1767个碱基,包涵2个开放阅读杠(ORF1和ORF2),分别编码与复制相关的Rep蛋白和结构蛋白Cap.通过BLAST对所测GD1株核苷核酸序列早国内外已登录GenBank中的PCV-2病毒核苷酸序更进行同源性比较,与PCV-2参考毒株的核苷酸同源性介于94.4%～99.7%之间,与德国株PCV-2(AF201897)的同源性最高,为99.7%;与猪I型圆环病毒(PCV-1)参考株(AY184287)的同源性仅为70%. 相似文献
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猪圆环病毒2型广西株的分离和全基因组序列分析 总被引：1，自引：1，他引：0
从广西表现为断奶仔猪多系统衰竭综合征的猪群中分离到1株猪圆环病毒2型(PCV-2),命名为GXB株.对GXB株的全基因组进行PCR扩增,扩增产物克隆至PMD18-T载体.测序结果表明,全基因组为1 767 bp,与GenBank上已知的8株PCV-2参考株序列的同源性在95.0%～99.6%之间.序列分析表明,GXB株基因组包含11个读码框(ORF),其中ORF1和ORF2是最主要的读码框,分别编码314个和233个氨基酸,与其他PCV-2毒株的ORF1、ORF2氨基酸的同源性分别为97.8%～100%、91.5%～98.7%.对GXB株ORF2编码的Cap蛋白基因进行功能分析,表明含有1个潜在的糖基化位点,3个明显的亲水区,有较强的抗原性和亲水性,为作为主要的免疫原性蛋白基因提供了依据. 相似文献
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参照GenBank中登录的猪圆环病毒2型(PCV-2)全基因组序列,设计合成了两对特异性引物,从甘肃白银疑似断奶仔猪多系统衰竭综合征(PMWS)病料中提取病毒DNA,分步扩增全基因组。回收PCR产物,将其插入pGEM-TEasy载体,构建了重组质粒pGEM-PCV-2,转化后筛选、提取阳性重组质粒进行测序。结果表明,克隆到的PCV-2全基因组长度为1767bp。应用DNAStar序列分析软件,对所测PCV-2序列与GenBank中登录的包括甘肃在内的国内外PCV毒株进行同源性分析。结果显示,克隆的PCV-2与英国株(UK-EU656143)遗传关系最近,其核苷酸和推导的氨基酸序列同源性高达96.2%和91.0%,与已报道的2株甘肃毒株(GS03-EU547458,GSLZ-FJ447482)遗传关系较远,可能是流行于甘肃白银的一个变异毒株(GSBY)。 相似文献
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华南地区猪圆环病毒1型与2型感染情况调查及相互关系 总被引：1，自引：0，他引：1
根据已发表的猪圆环病毒1型(PCV-1)与猪圆环病毒2型(PCV-2)的全基因组序列,设计4对特异性引物,用套式PCR方法对广东地区的规模养猪场或个体养殖户送检的144份猪血清进行了PCV-1与PCV-2病毒检测.结果显示PCV-1阳性血清21份,PCV-2阳性血清40份,PCV-1与PCV-2均为阳性的血清7份,PCV-1阳性率为14.6%,PCV-2阳性率为27.8%;PCV-1与PCV-2均为阳性的阳性率为4.9%,从数据上的比较可知PCV-2的感染率高于PCV-1的感染率.说明PCV-2感染比较普遍,患病猪群中也存在一定比例的PCV-1病毒感染. 相似文献
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根据GenBank已发表的猪圆环病毒2型（PCV-2）全基因组序列,设计2对特异性引物,对山东省不同地区规模化猪场采集的疑似断奶仔猪多系统消耗综合征（PMWS）组织病料进行了PCV-2全基因组克隆和序列分析。结果表明,PCV-2核苷酸序列较稳定,不同地区8个PCV-2毒株全基因组序列均由1 767 bp组成,彼此间核苷酸序列同源性达97.3%～99.8%,亲缘关系密切;与GenBank已发表的PCV-2参考毒株的同源性介于95.6%～99.8%。而ORF2的核苷酸序列同源性只有91.6%～99.9%。 相似文献
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毋艳萍 《国外畜牧学(猪与禽)》2014,(5):50-53
根据Genbank已发表的猪圆环病毒Ⅱ型(PCV-2)全基因组序列,设计两对特异性引物,建立了PCV-2全基因组的克隆和序列分析方法,并对甘肃省两个规模化养猪场采集的疑似PMWS病料进行了全基因克隆和序列分析,确定了PCV-2毒株基因序列的变异情况。结果表明,PCV-2核苷酸序列稳定,1株标准株与2株分离株全基因序列均由1 768 bp组成,彼此间序列的同源性达94.0%~99.8%,2个分离株之间同源性达94.2%~99.8%;分离株与标准株和Genbank已发表的23株PCV-2毒株参考毒株同源性达92.6%~100%。 相似文献
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参考GenBank中发表的猪圆环病毒2型(PCV-2)全基因序列,设计一对PCR引物,从病料中扩增获得4株PCV-2的全基因组序列,分别命名为SDNY-PCV-2、ShD-PCV-2、HBbd-PCV-2、GSLN-PCV-2,经测序确定长度均为1 767 bp。应用DNA Star序列分析表明,4个PCV-2分离株与国外部分分离株的核苷酸序列同源性达95.5%~99.8%,与PCV-1毒株的序列同源性为76.2%~77.6%。与国内外部分分离毒株序列进化树分析表明,4个PCV-2分离毒株处于不同分支中,存在一定差异。 相似文献
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利用体外环化的猪圆环病毒2型(PCV-2)全基因的感染性,建立一种分离PCV-2的方法。根据GenBank中PCV-2的基因序列,设计合成1对扩增PCV-2全基因组的特异性引物。通过PCR方法从广东发病猪病料扩增到PCV-2全基因组片段,将该片段克隆入pMD18-T载体,筛选获得阳性重组质粒pM-DT-YF并测序。将所测序列与GenBank中发表的PCV毒株序列进行同源性比较。将质粒pMDT-YF大量扩增,经SacⅡ酶切质粒得到PCV-2全基因组,通过T4连接酶体外环化后,脂质体介导转染PK-15细胞,盲传8代。用间接免疫荧光抗体试验(IFA)可检测到特异性荧光。将转染细胞稀释后接96孔细胞培养板,培养3 d。用荧光定量法检测各孔的PCV-2拷贝数,选择拷贝数最大的细胞扩大培养,经IFA法测定病毒滴度显著增加。结果表明,利用具有感染性的体外环化的全基因组的克隆转染PK-15细胞,并通过选择压力可获得较高滴度的具有感染性的PCV-2。 相似文献
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为了监测河北省及周边地区猪圆环病毒2型(Porcine circovirus 2,PCV-2)的流行性和遗传变异性,试验采集河北省及周边地区猪场疑似患断奶仔猪多系统衰竭综合征(PCVAD)仔猪的组织病料,提取DNA,采用PCR方法进行PCV-2全基因组扩增、克隆和测序,采用DNAStar软件对PCV-2测序结果进行剪辑、拼接和同源性分析,利用MEGA X 10.0.5软件对PCV-2基因组进行遗传进化分析,利用RDP4软件对PCV-2基因组进行重组分析。结果表明：成功扩增并克隆出6株PCV-2毒株的基因组序列,6株分离株分别为河北沧州株HB/NG/2020(OM524507)、HB/WT/2020(OM524511)和HB/CZ/2020(OM524512),河北邯郸株HB/WA/2020(OM524508),河北邢台株HB/ZZ/2020(OM524509)及内蒙古乌兰察布株NMG/QQ/2020(OM524510);经测序和全长拼接,PCV-2基因组长度均为1 768 bp。经同源性分析,6株PCV-2毒株基因组核苷酸序列的同源性为97.8%～100%,与4株国产疫苗参考株LG、Z... 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