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不同引物RT-PCR方法检测猪繁殖与呼吸综合征病毒的比较研究 总被引：9，自引：5，他引：9
用3对分别针对猪繁殖与呼吸综合征病毒(PRRSV)的ORF7、ORF5和ORF5的PCR引物N1/N2、AdGP5.1/AdGP5.2和RFLP5.1/RFLP5.2进行RT-PCR,检测PRRSV,从其敏感性、特异性和临床样品检出率等方面进行比较,在此基础上进一步建立一步法RT-PCR检测方法。结果显示:3对引物对PRRSV均有很高的特异性;应用N1/N2引物病毒最低检测量为7.9 TC ID50,而AdGP5.1/AdGP5.2引物和RFLP5.1/RFLP5.2引物PCR最低检测量为79 TC ID50;运用N1/N2、AdGP5.1/AdGP5.2和RFLP5.1/RFLP5.2引物分别进行RT-PCR扩增检测临床样品,PRRSV检出率分别为28/48、27/48和25/48,且用AdGP5.1/AdGP5.2和RFLP5.1/RFLP5.2引物检测的阳性样品,用N1/N2引物检测也都呈阳性。运用N1/N2引物,通过一步法RT-PCR成功地从PRRSV S1株中扩增出374 bp的目的基因片段。结果表明,用N1/N2引物扩增PRRSV目的基因,其敏感性和临床样品检出率更高,更适合临床样品PRRSV的检测。 相似文献
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Wesley RD Mengeling WL Lager KM Vorwald AC Roof MB 《American journal of veterinary research》1999,60(4):463-467
OBJECTIVE: To determine stability of the restriction fragment length polymorphism (RFLP) pattern of a porcine reproductive and respiratory syndrome vaccine virus and patterns of other viral strains as they replicate in pigs. SAMPLE POPULATION: Field samples of porcine reproductive and respiratory syndrome virus (PRRSV) and samples from 2 weaned pigs, 2 nursery-age pigs, and 5 gilts experimentally infected with PRRSV. PROCEDURE: PRRSV was isolated from field samples, experimentally infected pigs, or pigs that were in contact with experimentally infected pigs. For each virus, RNA was isolated from infected cells, and RFLP patterns were determined. RESULTS: 61% of field samples had 2-5-2 RFLP patterns characteristic of the vaccine virus, 32% had field virus RFLP patterns, and 7% had intermediate RFLP patterns that indicated a virus with a close relationship to the vaccine virus. Viruses isolated from experimentally infected pigs had no change in RFLP patterns after up to 13 weeks of in vivo replication and transmission to contact pigs. CONCLUSIONS AND CLINICAL RELEVANCE: RFLP patterns distinguish the vaccine and field strains of PRRSV; however, as the vaccine virus spreads among a swine population, the RFLP pattern can change to a related intermediate pattern. A glycine at residue 151 of open reading frame 5 is another marker for the vaccine virus; this glycine is rapidly lost and eventually replaced with arginine as the vaccine virus replicates in pigs. 相似文献
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PRRSV NC株ORF3基因的克隆、序列分析及表达 总被引：1，自引：0，他引：1
为原核表达猪繁殖与呼吸综合征病毒(PRRSV)的ORF3基因,本研究根据GenBank登录PRRSV美洲株ATCC VR2332的ORF3基因序列,利用Primer 6.0软件设计合成一对特异性引物,经RT-PCR扩增得到了大小为765bp的片段。将扩增的ORF3基因截短为495bp和750bp片段分别克隆于原核表达载体pGEX-KG中,在IPTG的诱导下进行Gp3重组蛋白的截短表达,经western blot检测证实表达的2种截短重组蛋白均具有良好的与抗体的反应活性,从而为进一步研制新型疫苗提供了实验依据。 相似文献
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我国五省区部分猪场高致病性猪蓝耳病毒感染情况检测与分析 总被引：2，自引：0，他引：2
对2008年-2009年我国五省区发病猪场235份、屠宰场的218份样品进行了高致病性猪蓝耳病病毒(HP-PRRSV)RT-PCR检测,挑选具有代表性的HP-PRRSV阳性样品进行HP-PRRSV ORF5基因扩增、测序及分析.结果表明,这五个省区发病场蓝耳病的检出率平均74.6%.屠宰场的检出率平均44%,混合感染主要以二重感染为主,且发病场较屠宰场严重.对获得的13株HP-PRRSV ORF5进行测序分析,发现序列长度均为603 bp,未见缺失或插入,仅在9 aa～29 aa存在点突变;序列比较发现,与普通株标准序列VR-2332株核苷酸同源性达85.9%～87.2%;与高致病性毒株的同源性JXA1-06核苷酸同源性达96.0%～99.0%.而其推导氨基酸序列与普通型、高致病性毒株的同源性分别为87.1%～88.1%和97.5%～98.0%.从遗传进化以及变异情况看,获得的PRRSV ORF5序列均为与JXA1类似的高致病性PRRSV序列,与JXA1和HB-1同属美洲型中的一个亚群. 相似文献
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欧洲型PRRSV RT-PCR检测方法的建立及ORF7基因序列比较 总被引：1，自引：0，他引：1
根据PRRSV(LV株)ORF7基因设计一对引物,建立了欧洲型PRRSV的RT-PCR检测方法.通过对50份组织病料检测及其ORF7基因序列分析,结果表明,有4份组织病料扩增出欧洲型PRRSV 576bp特异性片段,阳性率为8%,其ORF7基因序列和氨基酸推导序列与欧洲型PRRSV弱毒疫苗株(AMERVAC-PRRS)的同源性分别在99.0%～99.7%和98.5%～100%之间,而与标准毒株(LV)的同源性分别在95.9%～96.6%和96.9%～97.7%之间.表明该PT-PCR体系适合组织病料中欧洲型PRRSV的直接检测,同时也证实了欧洲型PRRSV在我国的存在,并且与疫苗株之间具有较高的同源性. 相似文献
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Hye Kwon Kim Jeong Sun Yang Hyoung Joon Moon Seong Jun Park Yuzi Luo Chul Seung Lee Dae Sub Song Bo Kyu Kang Soo Kyung Ann Chan Hyuk Jun Bong Kyun Park 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(2):121-130
The 23 open reading frame (ORF) 5 sequences of Korean type II porcine reproductive and respiratory syndrome virus (PRRSV) were collected from viremic sera from the (modified live vaccine) MLV-vaccinating and non-vaccinating farms from 2007 to 2008. The samples were phylogenetically analyzed with previous ORF5 sequences, including type I Korean PRRSV, and previously reported or collected sequences from 1997 to 2008. A MN184-like subgroup of type II Korean PRRSV was newly identified in the viremic sera collected from 2007 to 2008. And of the type I PRRSVs, one subgroup had 87.2~88.9% similarity with the Lelystad virus, showing a close relationship with the 27~2003 strain of Spain. The maximum parsimony tree of type II PRRSV from 1997 to 2008 showed that they had evolved to four lineages, subgroups 1, 2, 3 and 4. Most of the recently collected type II PRRSVs belonged to subgroup 4 (48%). The region of three B-cell epitopes and two T-cell epitopes of ORF5 amino acids sequences was considerably different from the MLV in subgroups 3 and 4. In conclusion, the existence of type I PRRSV, which was genetically different from Lelystad virus (Prototype of type I PRRSV), and heterologous type II PRRSVs of viremic pigs detected even in the MLV-vaccinating farms indicated the need for new vaccine approaches for the control of PRRSV in Korea. 相似文献
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RT-PCR快速检测猪繁殖与呼吸综合征临床组织样品的研究 总被引：14，自引：3，他引：14
根据猪繁殖和呼吸综合征病毒(PRRSV)已发表的核苷酸序列 ,在其核衣壳蛋白基因 (ORF7)保守区设计了一对跨幅约 380bp的特异性引物N1/N2 ,对已知PRRSVJK10 0 1毒株和PRRS临床病料进行RT PCR扩增 ,均扩增出约 380bp的特异片段。用此方法检测 5份疑似PRRS病例肺组织病料 ,结果均为阳性 ,对 2个阳性样品扩增产物进行克隆、测序 ,全长均为 372bp ,与PRRSVVR 2 332毒株ORF7同源性为 95%,证实为PRRSV的核衣壳蛋白基因。结果表明 ,建立的RT PCR检测PRRS临床组织病料特异、快速 ,可用于PRRS临床病料检测 相似文献
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为建立能同时检测猪瘟病毒(CSFV)和猪繁殖与呼吸综合征病毒(PRRSV)的方法,针对CSFV和PRRSV的基因序列设计3对特异性引物,第1对引物扩增CSFV毒株NS2基因508bp片段,第2对引物扩增PRRSV美洲型经典毒株和变异毒株Nsp2基因338bp/248bp片段,第3对引物扩增PRRSV欧洲型毒株ORF5基因614bp片段。经过反应条件的优化,建立了能同时检测并区分CSFV毒株和PRRSV美洲型经典毒株、变异毒株及欧洲型毒株的多重RT-PCR方法。该方法可以特异扩增CSFV和PRRSV,而与猪口蹄疫病毒(FMDV)、猪伪狂犬病病毒(PRV)、猪细小病毒(PPV)、猪圆环病毒2型(PCV-2)均无交叉反应;对CSFV和PRRSV 4种重组质粒标准品的检出下限均为1.67×103拷贝/μL。对采集的106份临床疑似病料进行检测,结果CSFV和PRRSV变异株混合阳性4份,占3.77%(4/106);CSFV阳性7份,占6.60%(7/106);PRRSV变异株阳性17份,占16.04%(17/106)。结果表明,建立的多重RT-PCR检测方法可以用于CSFV和PRRSV的临床快速鉴别诊断和流行病学调查。 相似文献
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为了解2010年河北省猪繁殖与呼吸综合征病毒变异趋势,用RT—PCR方法对2010年河北省发病猪场的病料进行PRRSV Nsp2和0RF5基因扩增、克隆和测序,利用DNAStar软件对所测序列进行分析。结果显示,扩增的Nsp2基因氨基酸序列相似性为91．4％～98．8％,与GenBank中参考毒株的氨基酸序列相似性为6... 相似文献
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猪繁殖与呼吸综合征病毒(PRRSV)协同感染细菌性疾病的分析研究 总被引：1，自引：1，他引：0
为了解湖北某养殖场猪繁殖与呼吸综合征病毒（porcine reproductive and respiratory syndrome virus,PRRSV）流行毒株的遗传变异和临床感染情况,试验采集10份疑似PRRS发病仔猪的肺脏、淋巴结等临床样品,应用RT-PCR方法扩增PRRSV的Nsp2部分基因用于定性检测分析,并对扩增的其中2份PRRSV阳性样品进行ORF5基因核苷酸序列测定,结合不同疫苗毒株开展同源性比对分析。为进一步揭示病因,通过多重PCR方法对10份发病猪的肺脏和12份鼻拭子样品进行了相关致病菌的鉴定,并对其中的2株不同病原菌开展药敏试验。结果显示,10份临床样品中有5份检测到美洲型变异PRRSV,病原阳性率为50%。ORF5全基因序列分析表明,2个流行毒株间的核苷酸同源性为99.7%,与以TJM-F92、JXA1-R、HuN4-F112等为代表的高致病性致弱疫苗毒株核苷酸同源性最高,为96.7%~97.0%;与美洲型标准毒株VR2332的同源性分别为87.6%和87.9%;与国内较早分离的经典毒株（CH-1R和R98株）的核苷酸同源性分别为92.9%和87.4%、87.7%。患病猪临床常见感染模式为PRRSV+PM+SS、PRRSV+PM或PRRSV+HPS,2株主要致病菌药敏试验表明,多杀性巴氏杆菌对头孢曲松、阿莫西林等药物高度敏感,猪链球菌对阿莫西林、氨苄西林、阿奇霉素等药物高度敏感。本研究揭示了该场保育猪的发病病原,并从分子水平明确了临床PRRSV与不同疫苗毒株的亲缘关系,为弱毒疫苗的合理选择使用和综合防控PRRS提供了实践依据。 相似文献
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参照GenBank中已发表的有关基因序列,分别设计合成针对PCV-2、PRRSV和CSFV的3对引物,分别建立检测临床病例中PCV-2、PRRSV和CSFV感染的PCR或RT-PCR方法。结果显示,扩增产物经琼脂糖凝胶电泳,分别各呈现1条大小约1154,372,375bp的特异条带。采用建立的PCR方法对江西各地发病猪和死亡猪的133份临床病料进行PCV-2检测,结果总检出率53.38%(71/133)。在71份PCV-2阳性的病料中检测出PRRSV20份,阳性率28.17%(20/71);CSFV9份,阳性率12.68%(9/71);PRRSV和CSFV共同感染9份,阳性率12.68%(9/71)。 相似文献
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为了解广东省猪繁殖与呼吸综合征病毒(PRRSV)流行毒株ORF5基因遗传变异情况,采用RT-PCR对2018年采自广东部分地区疑似患有PRRS的猪肺组织样品进行PRRSV ORF5基因扩增以及克隆测序,并进行生物信息学分析。结果表明,成功扩增出18株PRRSV流行毒株的ORF5基因片段。ORF5基因序列分析表明,18株PRRSV流行毒株ORF5基因核苷酸同源性为83.7%~99.8%,PRRSV流行毒株与参考毒株的同源性为62.1%~99.8%。基于ORF5基因的遗传进化树分析表明,18株PRRSV流行株均为美洲型毒株。其中,10株与以JXA1为代表的高致病性毒株亲缘较近,2株与新型高致病性毒株FZ16A相似;1株与以NT1为代表的疫苗返强毒株亲缘较近,1株与以R98为代表的疫苗毒株亲缘性较近,4株与广东新报道的GM2和QYYZ毒株亲缘性较近。DNA推导氨基酸序列分析表明,18株流行株的氨基酸序列与国内已报道的代表株相比发生不同程度的变异,GP5抗原表位上存在着差异。研究结果揭示了广东地区PRRSV有新型强毒株、重组毒株以及疫苗返强毒株的流行,提示养殖者谨慎、合理使用疫苗,防止疫苗毒株返强和毒株重组,为该地区防控PRRS提供参考。 相似文献
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为了解猪繁殖与呼吸综合征病毒（PRRSV）在湖南省地方猪保种场的感染情况,本研究在2019－2020年间从湖南省2个地方猪保种场采集287份全血样品。首先将血样混合成41份,采用RT-PCR或PCR法进行PRRSV病原检测,进一步通过高保真PCR扩增从PRRSV阳性样品中扩增PRRSV ORF5基因;测序后利用DNAStar软件分析获得的ORF5基因及其编码的GP5氨基酸与国内外不同PRRSV毒株的遗传进化关系;最后用PRRSV阳性血清接种Marc-145细胞,经盲传分离毒株,并用Reed-Muench法测定病毒滴度。结果显示,检测的41份混样中有3份PRRSV病原核酸呈阳性;从PRRSV阳性混样中单独扩增获得6条PRRSV ORF5基因序列,均属于PRRSV-2型的lineage 8分支,相似性为99.2%~99.8%;6条ORF5基因编码的GP5蛋白氨基酸序列在信号肽区域（第23位）、潜在的N-糖基化位点（第33位）和表位C （第59位）存在差异;PRRSV阳性血清接种Marc-145细胞盲传5代后出现明显的细胞病变,获得1株PRRSV毒株,命名为NX-1,病毒TCID50为4×105/mL。本研究表明,湖南省地方猪保种场存在PRRSV感染,感染的PRRSV属于PRRSV-2型的lineage 8,其GP5氨基酸序列存在的多处变异可能是造成疫苗免疫失败的原因之一,以上结果可为湖南省地方猪保种场的免疫防控提供一定参考。 相似文献
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Pesente P Rebonato V Sandri G Giovanardi D Ruffoni LS Torriani S 《Veterinary microbiology》2006,114(3-4):214-224
We investigated the dynamics of porcine reproductive and respiratory syndrome virus (PRRSV) variability in a range of swine PRRS-positive farms located in Northern Italy, to provide insights into the epidemiology and diffusion of the virus, particularly throughout the entire swine production chain. In this context, we also examined the effectiveness and the critical points of a recently developed gilts acclimatization program in swine breeder farms. To achieve these aims, we designed new primers and determined 64 complete open reading frame 5 (ORF5) sequences, representing Italian PRRSV field strains and the European vaccine Porcilis strain (Intervet); in addition, the more conserved ORF7 of 11 PRRSV strains were sequenced. The domains' prediction of their putative protein sequences was performed as well. Based on these sequences, phylogenetic trees were inferred which revealed a high degree of variability among the PRRSV Italian strains. The outcomes of the phylogenetic analysis showed that the most frequent source of infection in PRRS-positive farms (sow herds, nursery sites, fattening units) was the introduction of animals carrying a new variant and not the modification of already present variants; moreover, the integration of data from phylogenetic analysis and from the clinical and serological status of the swine herds suggested that the acclimatization program could be a valid tool to stabilize the PRRS clinical picture in farms, only when applied in combination with rigorous bio-security routine management and avoid the incoming of new PRRSV variants. 相似文献
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Evaluation of the presence of porcine reproductive and respiratory syndrome virus in pig meat and experimental transmission following oral exposure 总被引：1，自引：0，他引：1 
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下载免费PDF全文 A study was performed to evaluate the presence of porcine reproductive and respiratory syndrome virus (PRRSV) in pig meat collected at slaughterhouses and its potential transmission to pigs via pig meat. A total of 1039 blood samples were collected from pigs upon their arrival at the abattoir. The following day, meat samples (n = 1027) were collected from the carcasses of these same pigs. Samples originated from 2 Canadian slaughterhouses, 1 situated in the province of Quebec and the other situated in the province of Manitoba. Serum samples were tested for antibodies to PRRSV and both serum and meat samples were also tested for PRRSV nucleic acid by polymerase chain reaction (PCR). Seropositivity to PRRSV for all serum samples was 74.3%. Furthermore 45 (4.3%) of the total serum samples and 19 (1.9%) of the 1027 meat samples were positive for PRRSV by PCR. Sequence analysis of open reading frame (ORF) 5 performed on 15 of the 19 PRRSV strains identified in pig meat indicated that 9 were field strains and 6 were vaccine-like (98% to 99.7% nucleotide homology with the Ingelvac RespPRRS/Repro vaccine). One of these 6 strains presented an intermediate 2-6-2 restriction fragment length polymorphism (RFLP) cut pattern and the others showed the characteristic 2-5-2 RFLP pattern of the vaccine strain. All strains sequenced were determined to be North American strains. In only 1 of the 19 PRRSV-positive meat samples could PRRSV be isolated. To test the potential infectivity of meat samples containing residual PRRSV, 11 of the PCR-positive meat samples (weighing 1.05 to 1.8 kg) were each used in feeding experiments of 2 PRRSV antibody-negative specific pathogen-free pigs of 9 wk of age. Samples were cut into several pieces and fed to each pair of pigs on 2 consecutive days. Each pig pair was housed in a separate cubicle and serum samples were collected at -7, 0, 7, 14, and 20 to 21 days post exposure. Seven pig pairs were found to be infected by PRRSV following ingestion of meat samples, including meat samples containing vaccine-like virus, as judged by the demonstration of PRRSV antibodies and/or PRRSV nucleic acid in the serum. In summary, the present study indicated that low residual quantities of PRRSV may be found in a small percentage of pig meat collected at slaugtherhouses. Furthermore, when this meat was fed raw to pigs in the experimental setting designed, pigs could be infected by PRRSV. 相似文献