共查询到20条相似文献，搜索用时 31 毫秒
1.
M. Cortey E. Pileri M. Sibila J. Pujols M. Balasch J. Plana J. Segalés 《Veterinary journal (London, England : 1997)》2011,187(3):363-368
Changes in porcine circovirus type 2 (PCV-2) genotypes were evaluated before, during and after outbreaks of post-weaning multisystemic wasting syndrome (PMWS) in (1) a retrospective study using pig sera collected in Spain from 1985 to 2008 and (2) a longitudinal study using pig sera collected from two farms in Spain over periods of 7 and 14 years. In both studies, there was a rapid genotypic shift from PCV-2a to PCV-2b that was related to the peak of PMWS epizootics in Spain and the appearance of PMWS on the two farms studied longitudinally. 相似文献
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Postweaning multisystemic wasting syndrome of pigs in Korea: prevalence, microscopic lesions and coexisting microorganisms 总被引：10，自引：0，他引：10
Kim J Chung HK Jung T Cho WS Choi C Chae C 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(1):57-62
A retrospective study was performed on natural cases of postweaning multisystemic wasting syndrome (PMWS), recorded from January 1999 to December 2000, to determine the prevalence, microscopic lesions, and other coexisting pathogens associated with PMWS. PMWS is diagnosed based on three criteria: the presence of clinical signs (retardation of growth), characteristic microscopic lesions (granulomatous inflammation and inclusion body), and the presence of porcine circovirus (PCV)-2 within these lesions. One hundred and thirty three (8.1%) of the 1634 pigs submitted from 1243 pig farms were diagnosed for PMWS. The affected pigs were from 25 to 120 days old, the majority (78 cases, 58.6%) being 60 to 80 days old. PMWS occurred each month during the two-year study period, but the incidence peaked in May (38 cases, 28.6%), followed by April (18 cases, 13.5%) and June (13 cases, 9.8%). The most consistent and characteristic lesions were multifocal, granulomatous inflammation in lymph nodes, liver and spleen, characterized by infiltration of epithelioid macrophages and multinucleated giant cells. The majority of cases (113 cases, 85.0%) was dual infection with other pathogens. The combination of PCV-2 and Hemophilus parasuis (43 cases, 32.3%) was shown to be the most prevalent followed by PCV-2 and porcine reproductive and respiratory syndrome virus (39 cases, 29.3%). The consistent presence of PCV-2, but lower prevalence of other viral and bacterial pathogens in all pigs examined with PMWS, has led to the speculation that PCV-2 is the etiological agent causing PMWS. 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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上海地区出现猪繁殖与呼吸综合征和2型猪圆环病毒混合感染 总被引：21，自引：2，他引：19
上海地区6个规模化猪场断奶后仔猪出现全身消耗性综合征，剖检的18头病仔猪都表现肺脏严重病变和淋巴结肿大出血。分别设计针对猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus，PRRSV)N蛋白和2型猪圆环病毒(porcine circovirus type2，PCV-2)部分基因的特异性PCR引物，通过RT—PCR和PCR技术从患病猪肺脏组织均扩增出PRRSV和PCV-2的特异基因片段。结合临床症状和流行病学调查，证实上海地区出现PRRSV和PCV-2的混合感染。 相似文献
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A review of porcine circovirus 2-associated syndromes and diseases 总被引：25，自引：0，他引：25
Chae C 《Veterinary journal (London, England : 1997)》2005,169(3):2012-336
Clinical expression of porcine circovirus 2 (PCV2) infection in swine may result in several distinct syndromes and diseases including post-weaning multisystemic wasting syndrome (PMWS), porcine dermatitis and nephropathy syndrome (PDNS), reproductive failure, porcine respiratory disease complex, granulomatous enteritis, necrotizing lymphadenitis, and possibly exudative epidermitis. Association of PCV2 with congenital tremor in piglets is still controversial. The extent of the involvement of PCV2 in swine disease other than PMWS is currently poorly understood. This review concentrates on PCV-2-associated syndromes and diseases other than PMWS. 相似文献
6.
Cao S Chen H Zhao J Lü J Xiao S Jin M Guo A Wu B He Q 《Veterinary research communications》2005,29(3):263-269
Multiplex PCR was established to detect porcine circovirus type 2 (PCV-2), porcine parvovirus (PPV) and porcine pseudorabies virus (PRV) and applied to samples from 137 piglets exhibiting clinical signs of postweaning multisystemic wasting syndrome (PMWS). PCV-2 DNA was detected from all samples. Moreover, 43 samples were positive for PPV but negative for PRV; 11 samples were positive for PRV but negative for PPV; and 35 samples were positive both for PPV and PRV. These results suggests that PCV-2 co-infection with PRV and PPV may play an important role in PMWS. Also, multiplex PCR is an appropriate candidate method for diagnosis of PCV-2, PRV and PPV simultaneously in field cases. 相似文献
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Prevalence of infection with porcine circovirus-2 (PCV-2) and porcine reproductive and respiratory syndrome virus (PRRSV) in an integrated swine production system experiencing postweaning multisystemic wasting syndrome 
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下载免费PDF全文 Lorenzo Fraile Maria Calsamiglia Enric Mateu Anna Espinal Anna Cuxart Chiara Seminati Marga Martín Mariano Domingo Joaquim Segalés 《Canadian journal of veterinary research》2009,73(4):308-312
The objective of this study was to evaluate the prevalence of infection with porcine circovirus-2 (PCV-2) and porcine reproductive and respiratory syndrome virus (PRRSV) through a longitudinal study in an integrated swine production system (7 farms) experiencing postweaning multisystemic wasting syndrome (PMWS). Risk factors for PCV-2 infection and for PCV-2 and PRRSV coinfection were also evaluated. Fifteen sows from each herd and 4 non-cross-fostered piglets from each sow were randomly selected at farrowing and ear-tagged at birth. Serum samples were analyzed for antibodies to PCV-2 and for detection of the PCV-2 and PRRSV genomes. Statistical analyses involved 2 approaches. The 1st approach characterized the dynamics of PCV-2 infection and their relationship with PRRSV infection. The 2nd approach analyzed the probability of being infected by PCV-2 or by both PCV-2 and PRRSV through a generalized linear mixed model incorporating sow and farm characteristics. At the 1st sampling time (1 wk of age), there was a significant relationship between sow PCV-2 infection and piglet PCV-2 infection (P < 0.0001). The risk of PCV-2 and PRRSV coinfection was 1.85 times greater in piglets from a sow with low titers of PCV-2 antibodies than in piglets from sows with medium to high titers (P = 0.03) and was 2.54, 2.40, and 2.02 times greater, respectively, in piglets from primiparous sows, PCV-2-infected sows, and farms in an area of high pig density than in piglets from sows of higher parity (P = 0.004), noninfected sows (P = 0.04), and farms in a low-density area (P = 0.09). 相似文献
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Postweaning multisystemic wasting syndrome (PMWS) is a worldwide emerging disease of weaned piglets. The objective of this review is to summarize the current knowledge regarding PMWS, its causative agent, mode of transmission, diagnostic techniques to detect PCV-2, the possible control measures, and the association of PMWS and PCV-2 with porcine dermatitis and nephropathy syndrome (PDNS). The causative agent of PMWS is porcine circovirus type 2 (PCV-2), however, not all pigs infected with PCV-2 develop the syndrome. PCV-2 is consistently associated with PMWS and PMWS is considered not to occur without it. Both the syndrome and the virus are not regarded as new. Co-factors that could activate PCV-2 to cause PMWS are considered. This enigmatic nature of both the syndrome and the virus is triggering a concern towards uncertainties of the viral transmission, its introduction in to the herd, effective tools of diagnosis, and control strategies. 相似文献
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猪圆环病毒病研究进展 总被引：11，自引：0，他引：11
猪圆环病毒病是最近 1 0多年来才发现的一种新的猪病。研究表明 ,Ⅱ型猪圆环病毒 (PCV 2 )不仅是断奶仔猪多系统衰竭综合症 (PMWS)的病原 ,而且能够引起多种猪病。近年来 ,由PCV 2引起的疾病主要有PMWS、猪皮炎及肾病综合征、猪增生性坏死性肺炎等 ,另外 ,猪呼吸与繁殖障碍综合征、猪细小病毒、传染性先天性震颤等均与PCV 2感染有重要关联。随着规模化养殖业的不断发展 ,由PCV 2引起的疫病呈上升趋势 ,给全世界养猪业带来了巨大的经济损失。为了探讨有效控制本病的方法 ,特对该病的病原学、流行病学、致病机理、诊断及防制措施的研究情况进行了综述 相似文献
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One-day-old gnotobiotic piglets were inoculated intranasally with in vitro passaged porcine circovirus 1 (PCV-1), PCV-2, and porcine parvovirus (PPV) alone or in combination (PCV-1/PCV-2, PCV-1/PPV, and PCV-2/PPV). Piglets were evaluated for 1) the development of porcine postweaning multisystemic wasting syndrome (PMWS), 2) distribution of viral antigens by immunochemistry, and 3) viremia and the presence of viral DNA in nasal and ocular secretions and feces. All single agent-infected piglets and piglets infected with PCV-1/PCV-2 or PCV-1/PPV were clinically asymptomatic. They were transiently viremic and seroconverted to homologous virus(es). At termination of the study on postinfection day (PID) 35, microscopic lesions were restricted to focal inflammatory cell infiltrates in livers and myocardia. One piglet given PCV-1/PPV was PPV viremic for 2 weeks after infection and had lymphangiectasia of the spiral and descending colon associated with granulomatous inflammation. All four PCV-2/PPV-inoculated piglets developed PMWS, characterized by sudden onset of depression and anorexia, icterus, and submucosal edema. One piglet became moribund on PID 27, and the remaining three piglets were euthanatized between PID 27 and PID 30 because of severe disease. Lymph nodes were small and the livers were mottled. Disseminated angiocentric granulomatous inflammation was present in all tissues examined except the brain. Multiple lightly basophilic intracytoplasmic inclusion bodies were identified in macrophages and histiocytes. PCV-2 antigen was widely distributed within macrophages; PPV antigen was sparse. Hepatocellular necrosis and bile retention were prominent. PCV-2 DNA was identified in ocular, fecal, and nasal secretions. Terminal sera contained antibodies to PPV (4/4) and PCV-2 (3/ 4). Production of PMWS in gnotobiotic swine appears to require PCV-2 and additional infectious agents such as PPV for full disease expression in gnotobiotic piglets. 相似文献
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Kiatipattanasakul-Banlunara W Tantilertcharoen R Suzuki K Albarenque SM Thanawongnuwech R Nakayama H Doi K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(5):449-452
A retrospective study for the detection of porcine circovirus 2 (PCV-2) DNA was conducted by nested PCR method in 16 cases of swine post-weaning multisystemic wasting syndrome (PMWS) in Thailand. Histopathology showed characteristic lesions of PMWS and intracytoplasmic viral inclusion bodies in macrophages infiltrating in lymphoid tissues. PCV-2 DNA was detected from formalin-fixed and/or formalin-fixed paraffin-embedded tissues from all pigs with PMWS. The amplified products were digested with Hae III. 相似文献
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Cate E. Dewey W. Thomas Johnston Loriena Gould Terry L. Whiting 《Canadian journal of veterinary research》2006,70(3):161-167
A case-control study to investigate the contribution of postweaning multisystemic wasting syndrome (PMWS) and Porcine circovirus type 2 (PCV-2) to deaths among piglets of nursery age (19 to 68 d) in Manitoba indicated a significant positive association between PCV-2 infection and an increased mortality rate in nursery pigs. The clinical syndrome PMWS was seldom recognized in case or control herds; however, PCV-2 infection was widespread at the herd level. Other factors more strongly associated with increased piglet mortality rate than herd level PCV-2 infection were Mycoplasma hyopneumonia infection, porcine reproductive and respiratory syndrome (PRRS), and diarrhea caused by Eschericia coli K88. Management factors associated with case herd status included close proximity to other herds, larger number of sows supplying pigs to the nursery, larger range in age and weight going into the nursery, the moving of lightweight pigs into another nursery room at the end of the nursery fill, and not using spray-dried plasma in the 1st nursery ration. These results highlight the host-agent-environment triad leading to high nursery-barn mortality rates. 相似文献
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Activation of the immune system is the pivotal event in the production of wasting disease in pigs infected with porcine circovirus-2 (PCV-2) 总被引：39，自引：0，他引：39
Porcine circovirus (PCV)-2, a newly described single-stranded circular DNA virus pathogen of swine is the cause of postweaning multisystemic wasting syndrome (PMWS). In gnotobiotic piglets, PCV-2 infection alone produces asymptomatic infection without evidence of overt PMWS. Gnotobiotic piglets infected with PCV-2 were injected with keyhole limpet hemocyanin in incomplete Freund's adjuvant (KLH/ICFA), and the effects on virus production and development of PMWS were determined. In the first experiment, piglets were injected subcutaneously on the left hip and shoulder, and viral burden was assessed in regional lymph nodes draining the injection sites and in contralateral lymph nodes 13-14 days after infection. Immune activation increased the number of virus antigen-positive cells in draining lymph nodes and increased the amount of infectious virus recovered by 1-4 log10. In a second experiment, the effects of injections of KLH/ICFA with or without concurrent stimulation of peritoneal macrophages by intraperitoneal injections of thioglycollate broth on induction of PMWS was assessed. All immunized piglets developed moderate to severe PMWS, whereas none of the piglets infected with PCV-2 alone developed PMWS. In PMWS-affected piglets, extensive replication of PCV-2 was documented by both immunocytochemistry and quantitative viral titrations. Thus, immune activation is a key component of the pathogenesis of PCV-2-associated PMWS in swine. 相似文献
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Kenji Kawashima Ken Katsuda Hiroshi Tsunemitsu 《Journal of veterinary diagnostic investigation》2007,19(1):60-68
To investigate the prevalence and features of postweaning multisystemic wasting syndrome (PMWS) in Japan, an epidemiological study was conducted in 692 weaned pigs with various clinical signs, commonly including wasting or weight loss, collected from 129 swine farms between 2000 and 2003. The presence of PMWS was diagnosed by the detection of characteristic histological lesions and moderate to large amounts of porcine circovirus type 2 (PCV2) antigen within the lesions in multiple lymphoid tissues. Postweaning multisystemic wasting syndrome was positive in 23.4% of pigs (162/692) over the course of the study, and occurred in 50.4% of the farms (65/129). Mortality in 30-120-day-old pigs in the farms positive for PMWS varied from 0.1 to 32.0%. No significant difference in mortality was seen between PMWS-positive and -negative farms (P = 0.1). However, mortality was significantly higher in the PMWS-positive farms where PMWS was diagnosed in more than 50% of the pigs examined compared to farms negative for PMWS (P = 0.02). These findings indicate that PMWS has spread widely in Japan. Moreover it may exist in variable forms in swine farms, including an epidemic form or a subtle endemic or sporadic form. A case-control study suggested that risk factors for the occurrence of PMWS include porcine reproductive and respiratory syndrome (PRRS) pneumonias and Mycoplasma hyorhinis infection. 相似文献
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华南地区猪圆环病毒和猪繁殖与呼吸综合征病毒检测分析 总被引：1，自引：0，他引：1
为了解华南地区猪圆环病毒及猪繁殖与呼吸综合征病毒的最新流行情况,采集了华南地区11个规模猪场各饲养阶段猪血清807份,用套式PCR(nPCR)检测猪圆环病毒1型(PCV-1)和猪圆环病毒2型(PCV-2);采集了若干猪场2010年1月至2011年8月期间有咳嗽、喘气、消瘦及疑似PDNS等临床症状的猪血清312份,以及无临床症状猪血清104份,以nPCR检测PCV-2,以一步法反转录PCR(RT-PCR)检测猪繁殖与呼吸综合征病毒。结果发现,所调查的11个规模猪场中只有5个检出PCV-1,所有猪场均检出PCV-2。PCV-2阳性率为30.61%,而PCV-1阳性率仅为4.21%;经产母猪和7周龄以上保育猪PCV阳性率最高;有临床症状的猪血清PCV-2阳性率为58.65%,PRRSV阳性率为37.82%,PCV-2阳性猪群中有39.89%的猪同时感染PRRSV;有症状猪群7月～9月的PCV-2感染率最高,而1月～3月最低;无临床症状猪血清PCV-2阳性率为27.9%,PRRSV阳性率为0.96%,PCV-2与PRRSV无混合感染。证明PCV尤其是PCV-2在华南地区仍广泛传播并流行,而且PCV-2与PRRSV混合感染致病情况较多。PCV-2的感染率与季节有一定的相关性,种猪带毒情况严重。 相似文献
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Ladekjaer-Mikkelsen AS Nielsen J Stadejek T Storgaard T Krakowka S Ellis J McNeilly F Allan G Bøtner A 《Veterinary microbiology》2002,89(2-3):97-114
Postweaning multisystemic wasting syndrome (PMWS) in swine is causally associated with the newly recognised pathogen, porcine circovirus type 2 (PCV2). In this study, 3-week-old SPF PCV2-seronegative piglets were inoculated intranasally with PCV2. The effect of immunostimulation on the induction of PMWS was investigated by immunisation with keyhole limpet hemocyanin (KLH) emulsified in incomplete Freunds adjuvant. The study was terminated 5 weeks after inoculation. While disease was not observed in the age-matched controls, two out of five non-immunised PCV2-infected piglets died on postinoculation day (PID) 21, and one was euthanized on PID 25 in moribund condition. These animals had appeared lethargic with persistent fever from PID 12 onwards. The euthanized pig appeared smaller than littermates and suffered from jaundice. At postmortem examination, gastric ulceration, icterus, and liver and thymus atrophy were observed. Furthermore, histological lesions of degenerating hepatocytes and hepatitis in combination with lymphoid depletion and syncytial cells in lymph nodes were consistent with the diagnosis of PMWS. One out of five immunostimulated PCV2-infected piglets was euthanized on PID 22 with convulsions after a period with wasting. This pig was lethargic from PID 14 onwards with persistent fever from PID 8 and transient dyspnoea. No differences in clinical signs, gross pathologic or histological findings were observed for the remaining non-immunostimulated and immunostimulated PCV2-infected piglets. All 10 PCV2-inoculated piglets seroconverted to PCV2 within 14 days after inoculation. By virus isolation, quantitative polymerase chain reaction (Q-PCR), and immunostaining of cryostat sections, it was demonstrated that lymphoid tissue contained abundant PCV2 antigen. Viral DNA load in serum samples was assessed by Q-PCR. All four PMWS-affected piglets had high levels of PCV2 DNA in serum, suggesting that there was a correlation between high levels of viral DNA in serum and the development of PMWS. In conclusion, infection with PCV2 caused PMWS in SPF piglets, however, the immunostimulation did not seem to play a critical role. 相似文献
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猪圆环病毒2型致病机制研究进展 总被引：2，自引：1，他引：2
猪圆环病毒2型(PCV-2)感染可导致一系列病征,包括断奶仔猪多系统衰竭征(PMWS)、仔猪先天性震颤(CT)、母猪繁殖障碍、猪皮炎肾病综合征(PDNS)及猪呼吸道综合征(PRDC),其中以PMWS对养猪业危害最大.PCV-2具有自身特有生物学特性.PCV-2可感染不同年龄段猪而产生临床上症状不同的疾病,能诱发仔猪产生免疫抑制后继发感染和混合感染其他病原.论文结合PCV-2的分子生物学特性和发病特征,从分子生物学角度、病毒组织嗜性、宿主细胞增殖特性及免疫刺激方面,对PCV-2致病机制进行综述,为防控PCV-2感染提供参考. 相似文献