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猪圆环病毒Ⅱ型感染的免疫抑制机理研究进展 总被引：3，自引：0，他引：3
猪圆环病毒感染是新发现的一种传染病。该病对猪的感染率较高,在世界范围内广泛发生,已成为严重影响养猪业发展的传染病之一。圆环病毒主要侵袭猪的免疫系统,干扰和破坏机体对疾病免疫抗体的产生和维持,致使抵抗力下降,从而容易继发或并发其他疾病。近年来,国内外学者对猪圆环病毒入侵免疫系统的机制做了大量研究,在病毒的复制机制、对细胞因子和淋巴细胞的影响以及与猪皮炎和肾病综合征的关系等方面均取得了一定的进展,为猪圆环病毒感染的预防和治疗奠定了基础。 相似文献
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猪圆环病毒病的流行病学、临床症状和防治 总被引：1，自引：0，他引：1
随着集约化、规模化的生猪养殖业的高效快速发展,养殖中出现的疾病也越来越多。猪圆环病毒病是由猪圆环病毒引发的传染病,该病毒是一种无囊膜的DNA病毒,是已知最小的动物病毒之一。不同年龄段的猪感染会表现出不同的临床症状,主要包括仔猪多系统衰竭综合征、猪皮炎肾病综合征等,给养猪业造成了巨大的经济损失。文章主要就猪圆环病毒病的流性病学、临床症状和防治等方面做出总结综述,为猪场对于猪圆环病的日常诊断及防控提供理论指导,也为后续的研究提供了参考。 相似文献
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猪圆环病毒感染诊断方法研究进展 总被引：2，自引：1，他引：1
猪圆环病毒分为1型和2型。目前还没有证据表明猪圆环病毒1型可以导致猪发病,但其在PK-15细胞中的广泛污染和在猪群中的高感染率已经引起了人们的高度关注,而猪圆环病毒2型的危害在于能够使感染猪只的免疫功能受到损害,这种可导致机体免疫抑制的病毒,由于经常以亚临床感染的形式出现,常易被忽视。为了更好地控制猪圆环病毒的感染,迫切需要寻找一种适合的快速准确的诊断方法。但目前在临床诊断和实验室的诊断过程中,单一的诊断方法往往受到多种因素的影响,这就需要根据目前各种检测猪圆环病毒的方法及其优缺点进行分析,应用多种方法相结合,优化检测手段,为寻找一种适合的快速准确的诊断方法、制定合理的免疫程序和发展新型的诊断方法提供参考。 相似文献
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猪繁殖障碍与呼吸道综合征病毒和猪圆环病毒2型混合感染的流行病学调查及综合诊断 总被引：5，自引：0，他引：5
猪繁殖障碍与呼吸道综合征（PRRS）和猪圆环病毒2型（PCV-2）是近几年来严重危害猪群的两大免疫抑制性疾病。为研究2种病毒自然条件下混合感染的发病情况，本研究分别利用RT-PCR和PCR方法，对近2年来自山东及周边地区78家猪场的237份临床病例进行了PRRSV和PCV-2的检测，结果发现PCV-2和PRRSV混合感染病例48份，阳性率达20.2%。2种病毒混合感染已成为该地区猪病流行的重要特征。本研究对该地区猪群混合感染的现状、发病表现及病变特征等进行了系统调查分析。 相似文献
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Coinfection by porcine circoviruses and porcine parvovirus in pigs with naturally acquired postweaning multisystemic wasting syndrome. 总被引：25，自引：0，他引：25
J A Ellis A Bratanich E G Clark G Allan B Meehan D M Haines J Harding K H West S Krakowka C Konoby L Hassard K Martin F McNeilly 《Journal of veterinary diagnostic investigation》2000,12(1):21-27
Postweaning multisystemic wasting syndrome (PMWS) is an emerging disease in swine. Recently, the disease has been reproduced with inocula containing a newly described porcine circovirus (PCV), designated PCV 2, and porcine parvovirus (PPV). In order to determine if these viruses interact in naturally acquired PMWS, affected tissues from field cases were examined by immunohistochemistry (IHC) and polymerase chain reaction (PCR) for PCV 2 and PPV, as well as by PCR for the other recognized porcine circovirus, PCV 1. Porcine circovirus 2 was detected by PCR or IHC in affected fixed or frozen tissues from 69 of 69 cases of PMWS collected over 3 years from 25 farms. Porcine parvovirus was detected in 12 of the same cases, and PCV 1 was detected in 9 of 69; however, an apparent decrease was found in the sensitivity of the PCRs used to detect the latter 2 viruses when fixed tissue from the same cases were compared with the use of frozen tissues. Porcine circovirus 2 was not detected by PCR in affected tissues from 16 age-matched pigs that had Streptococcus suis-associated disease. Electron microscopic examination of plasma pooled from 15 pigs with PMWS revealed the presence of PCV and PPV, whereas these viruses were not observed in pooled plasma from 5 age-matched clinically normal pigs. These results confirm and extend previous findings documenting a consistent association of PCV 2 with PMWS. As well, infection by PPV or PCV 1 or both may be an important cofactor in the pathogenesis of some, but apparently not all, cases of PMWS. 相似文献
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基于多重PCR的寡核苷酸基因芯片检测猪瘟病毒,猪繁殖与呼吸障碍综合征病毒及猪圆环病毒1型和2型 总被引：1，自引：0，他引：1
为了建立一种可同时检测区分猪瘟病毒(CSFV),猪繁殖与呼吸障碍综合征病毒(PRRSV)和猪圆环病毒2型(PCV-2)的寡核苷酸基因芯片方法,本研究针对每种病毒设计了4条～6条寡核苷酸探针,检测低限为1.6×104PCV-2拷贝数/μL,1.6×104CSFV拷贝数/μL,1.6×105PRRSV拷贝数/μL,比琼脂糖凝胶灵敏约10倍。利用建立的寡核苷酸基因芯片方法对76个仔猪样本进行了检测,检出了3种病毒的存在,其中25个样本(32.9%)同时感染了2种以上病毒。结果表明寡核苷酸基因芯片检测是一种快速、灵敏和高效的猪只混合感染病毒的病原学诊断方法。 相似文献
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Porcine circovirus type 2 (PCV2) is the essential infectious agent of postweaning multisystemic wasting syndrome (PMWS) considered as one of the most important swine diseases worldwide. One of the main risk factors reported for the development of PMWS is the PCV2 genotype. The presence of PCV2 in Cuban swine herds has been reported recently. However, genetic information about these viruses is not available yet. Hence, the objectives of this study were to classify the Cuban porcine circovirus type 2 sequences as well as to investigate the genetic diversity and the putative origins of the virus circulating in Cuban swine herds. PCV2 Cuban sequences appeared to be close related when an analysis of the entire viral genome sequences was performed. The main variations on amino acid sequences of the capsid protein were found within the immunoreactive areas. All the Cuban PCV2 sequences analyzed belonged to genotype 1 and were located within the same Cluster (1A). Interestingly, five of them were clustered with high confident values with those described as the PCV2 variants associated with severe porcine circovirus diseases reported in Canada from the late 2004 to 2006. Pigs imported from this source appeared to be the most probable origin of the viruses circulating in Cuban swine herds currently. The fact that one sequence was not clustered with any other group of PCV2 within genotype 1 might suggest that different introductions of the agent in the country from unknown sources have occurred. 相似文献
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猪圆环病毒免疫学研究进展 总被引：1，自引：0，他引：1
猪圆环病毒(PCV)在世界范围内广泛存在,可引起断奶仔猪多系统衰竭综合征(PMWS)、猪皮炎-肾病综合征(PDNS)和猪呼吸系统疾病症候群,给养猪业造成重大经济损失.已有研究表明,PCV-2感染和免疫刺激作用在PMWS发生中起关键作用,母源抗体对PMWS发生有被动保护作用,通过对初产母猪和经产母猪进行PCV-2免疫,增加母源性免疫和降低病毒血症的措施可以减少PMWS对仔猪死亡的影响.PCV-2疫苗现在已经在商业上应用,疫苗对PCV-2复制和PCVD的诱导增强作用似乎依赖于疫苗佐剂的类型和疫苗的接种时间.因此,基于有效的试验,在发生过PMWS感染的猪群,应该根据PCV-2感染的时间有目的地制定免疫接种方案,以控制或者减少PMWS的发生. 相似文献
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Case-control study on the association of porcine circovirus type 2 and other swine viral pathogens with postweaning multisystemic wasting syndrome. 总被引：19，自引：0，他引：19
Roman M Pogranichniy Kyoung-Jin Yoon Perry A Harms Steven D Sorden Michael Daniels 《Journal of veterinary diagnostic investigation》2002,14(6):449-456
A field-based case-control study was conducted to assess the strength of association of porcine circovirus type 2 (PCV2) and some major swine viruses with postweaning multisystemic wasting syndrome (PMWS). Cases were defined as individual pigs with a clinical history of progressive weight loss and histopathological lesions characteristic of PMWS. Controls were pigs without clinical signs and histopathological lesions typical of PMWS. A total of 31 cases and 56 controls was identified from diagnostic submissions. Serum and various tissues were collected from all animals and assayed for PCV, porcine reproductive and respiratory syndrome virus (PRRSV), porcine parvovirus, porcine enterovirus types 1-3, swine influenza virus, porcine respiratory coronavirus, transmissible gastroenteritis virus, porcine endogenous retrovirus, porcine lymphotropic herpesvirus type 1, and bovine viral diarrhea virus. The proportion of case and control pigs positive for each virus was determined and statistically compared for determining the strength of the association that each virus had with PMWS individually or in combinations. Porcine circovirus type 2 had the strongest association (OR = 9.3, P = 0.006) with PMWS among the viruses tested for. Risk for PWMS was much higher (OR = 31.2, P = 0.0009) if the animal was concurrently infected with PCV2 and PRRSV, suggesting that development of PMWS may be enhanced by cofactor(s). Because PCV2 was also found in 62.5% of the controls, PCV2 from 5 cases and 4 controls were selected and genetically compared. No significant genetic difference was observed between PCV2 from PMWS and control pigs. 相似文献
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Cecere TE Meng XJ Pelzer K Todd SM Beach NM Ni YY Leroith T 《Veterinary microbiology》2012,160(1-2):233-239
Porcine circovirus associated disease (PCVAD) is currently one of the most economically important diseases in the global swine industry. Porcine circovirus type 2 (PCV2) is the primary causative agent, however co-infection with other swine pathogens such as porcine reproductive and respiratory syndrome virus (PRRSV) is often required to induce the full spectrum of clinical PCVAD. While the specific mechanisms of viral co-infection that lead to clinical disease are not fully understood, immune modulation by the co-infecting viruses likely plays a critical role. We evaluated the ability of dendritic cells (DC) infected with PRRSV, PCV2, or both to induce regulatory T cells (T(regs)) in vitro. DCs infected with PCV2 significantly increased CD4(+)CD25(+)FoxP3(+) T(regs) (p<0.05) and DCs co-infected with PRRSV and PCV2 induced significantly higher numbers of T(regs) than with PCV2 alone (p<0.05). Cytokine analysis indicated that the induction of T(regs) by co-infected DCs may be dependent on TGF-β and not IL-10. Our data support the immunomodulatory role of PCV2/PRRSV co-infection in the pathogenesis of PCVAD, specifically via T(reg)-mediated immunosuppression. 相似文献
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猪圆环病毒病的特点 总被引：1，自引：0，他引：1
在最近几年中,养猪业遇到了越来越多的疾病,药物使用量显著增加,也使养殖场主、养殖户和兽医师感到非常的困惑。目前已经证实,猪圆环病毒病(Porcine Circovirus diaease,PCVD)在世界上广泛存在。可以引起断奶仔猪助多系统衰竭综合征(PMWS)、猪皮炎-肾病综合征(Porcine dermatitis and nephropathy syndrome,PDNS)和猪呼吸系统疾病症候群,给养猪业造成了巨大的经济损失。同时这一疾病常常与其他病毒或细菌性疾病发生混合感染,给猪病的防控带来了极大的困难。本文就猪圆环病毒病的某些特点作一简要论述。 相似文献
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YU Jing CHEN Yan-yong HE Xiao-jiang DAI Bing ZHAO A-yong WANG Xiao-du SONG Hou-hui 《中国畜牧兽医》2015,42(12):3173-3178
Porcine circovirus type 2 (PCV2) caused significant economic losses of swine industry,it's very important to establish a economy and rapid detection method.To strengthen the prevention and control of porcine circovirus disease,rapid and high sesitive detection method of PCV2 was established using nested PCR.According to PCV2 ORF2 gene conservative region,we designed two pairs of nested PCR primers,constructed ORF2 gene recombinant plasmid for standard template and optimizated the PCR reaction conditions to establish nested PCR detection method of PCV2 and detect the clinical samples of pig farms.Our results showed that the sensitivity and repeatability of this method were very high,the minimum detection level was 10 copies/μL and detection rate of clinical samples was 97.3%.In brief,the established nested PCR detection method of PCV2 in this study provided powerful means for quick and efficient detection of PCV2,and prevention and control of porcine circovirus disease in the swine industry. 相似文献
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猪圆环病毒2型(porcine circovirus type 2,PCV2)给养猪业造成了重大的经济损失,建立经济、快速的检测方法尤为重要。本研究旨在利用巢式PCR技术,建立高灵敏度PCV2检测平台,以加强对猪圆环病毒病的防控。根据PCV2 ORF2基因保守区,设计内、外2对巢式PCR引物,通过优化PCR反应条件,建立巢式PCR检测方法,并对猪场临床样本进行检测。结果显示,本研究建立的巢式PCR检测方法灵敏度高、重复性强,最低检出量为10拷贝/μL,检出率达97.3%。本研究建立的巢式PCR检测方法为快速、高效地检测PCV2以及为猪圆环病毒病的防控提供有力手段。 相似文献
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John Ellis Maria Spinato Choon Yong Keith West Francis McNeilly Brian Meehan Seamus Kennedy Edward Clark Steven Krakowka Gordon Allan 《Journal of veterinary diagnostic investigation》2003,15(4):364-368
Porcine circovirus 2 (PCV2) was first identified in high-health herds of domestic swine and was associated with a debilitating disease called postweaning multisystemic wasting syndrome (PMWS). Most subsequent studies have indicated that PCV2 infects only swine but there is little information on porcids other than improved breeds of domestic swine. Multisystemic disease was reported in a group of Eurasian wild boars raised under free-range conditions. Affected young pigs had pneumonia and enteritis and were cachectic. Porcine circovirus 2 was identified in affected tissue by immunohistochemistry and in situ hybridization, and a PCV2-like virus was isolated from pooled organs. The open reading frame (ORF2) of the isolated PCV2 had a 98.7% homology with the ORF2 of a reference PCV2 isolate. These diagnostic data indicate that PCV2 can infect and cause disease in Sus scrofa subspecies other than domestic swine. 相似文献
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Detection of respiratory pathogens in air samples from acutely infected pigs 总被引：2，自引：0，他引：2 
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下载免费PDF全文 Joseph R Hermann Susan L Brockmeier Kyoung-Jin Yoon Jeffrey J Zimmerman 《Canadian journal of veterinary research》2008,72(4):367-370
Pathogens causing significant respiratory disease in growing pigs include Porcine reproductive and respiratory syndrome virus, Porcine circovirus 2, swine influenza virus, porcine respiratory coronavirus, Mycoplasma hyopneumoniae, and Bordetella bronchiseptica. The objective of this research was to characterize the respiratory excretion of these pathogens by acutely infected pigs. Pigs were inoculated under experimental conditions with 1 pathogen. Samples were collected from the upper respiratory tract and exhaled air. All pathogens were detected in swabs of the upper respiratory tract, but only M. hyopneumoniae and B. bronchiseptica were detected in expired air from individually sampled, acutely infected pigs. These findings suggest either that the acutely infected pigs did not aerosolize the viruses or that the quantity of virus excreted was below the detection threshold of current sampling or assay systems, or both, at the individual-pig level. 相似文献
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Porcine endogenous retroviruses (PERV): in vitro artifact or a big problem for xenotransplantation?]
The pig is the favorized donor species for clinical xenotransplantation. However, PATIENCE et al. could show, that porcine endogenous retroviruses (PERV), released by a porcine kidney cell line, are capable of infecting human cell lines in vitro. Based on this discovery there is an ongoing discussion concerning the risks of zoonosis combined with xenotranplantation, which culminated in the demand for a moratorium on clinical transplantation of porcine organs. Recent findings exclude the possibility of an artifact due to the use of an immortalized cell line: Release of infectious PERV was also shown for mitogenic stimulated primary porcine peripheral blood mononuclear cells and, even more important, for primary porcine endothelial cells. In contrast, none of the recent retrospective in vivo studies showed evidence for PERV transmission, neither in patients after transplantation of porcine pancreas islet cells or after extracorporal perfusion of porcine kidneys, nor in baboons after transplantation of porcine endothelial cells. Currently it is not known, whether impairments of the immunological responses against foreign pathogens, which are associated with different xenotransplantation strategies, could enable PERV in vivo infection. Only in vivo experiments, if possible in suitable subhuman primate models, offer the prospect for a final risk assessment. 相似文献