1
|
Arruda B, Piñeyro P, Derscheid R, Hause B, Byers E, Dion K, Long D, Sievers C, Tangen J, Williams T, Schwartz K. PCV3-associated disease in the United States swine herd. Emerg Microbes Infect 2019; 8:684-698. [PMID: 31096848 PMCID: PMC6534263 DOI: 10.1080/22221751.2019.1613176] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Porcine circovirus-associated disease encompasses multiple disease syndromes including porcine circovirus 2 systemic diseases, reproductive failure, and porcine dermatitis and nephropathy syndrome. Until recently, porcine circovirus 2 was the only species associated with the porcine circovirus-associated disease. In this report, diagnostic investigations of thirty-six field cases submitted from multiple production systems, numerous sites and varied geographic locations demonstrated porcine circovirus 3 within lesions by in situ hybridization including fetuses with myocarditis, weak-born neonatal piglets with encephalitis and myocarditis, from cases of porcine dermatitis and nephropathy syndrome, and in weaned pigs with systemic periarteritis. Porcine circovirus 3 was detected by PCR in numerous fetuses and perinatal piglets at high viral loads (trillions of genome copies per mL of tissue homogenate). Samples from all cases in this study were assayed and found negative for porcine circovirus 2 by PCR. Metagenomic sequencing was performed on a subset of reproductive cases, consisting of sixteen fetuses/fetal sample pools. PCV3 was identified in all pools and the only virus identified in fourteen pools. Based on these data, porcine circovirus 3 is considered a putative cause of reproductive failure, encephalitis and myocarditis in perinatal piglets, porcine dermatitis and nephropathy syndrome, and periarteritis in swine in the United States.
Collapse
Affiliation(s)
- Bailey Arruda
- a Department of Veterinary Diagnostic and Production Animal Medicine , Iowa State University , Ames , IA , USA
| | - Pablo Piñeyro
- a Department of Veterinary Diagnostic and Production Animal Medicine , Iowa State University , Ames , IA , USA
| | - Rachel Derscheid
- a Department of Veterinary Diagnostic and Production Animal Medicine , Iowa State University , Ames , IA , USA
| | - Ben Hause
- b Cambridge Technologies , Worthington , MN , USA
| | | | - Kate Dion
- d The Hanor Company of Wisconsin, LLC , Enid , OK , USA
| | | | | | - Jon Tangen
- d The Hanor Company of Wisconsin, LLC , Enid , OK , USA
| | | | - Kent Schwartz
- a Department of Veterinary Diagnostic and Production Animal Medicine , Iowa State University , Ames , IA , USA
| |
Collapse
|
2
|
A Novel Porcine Circovirus Distantly Related to Known Circoviruses Is Associated with Porcine Dermatitis and Nephropathy Syndrome and Reproductive Failure. J Virol 2016; 91:JVI.01879-16. [PMID: 27795441 DOI: 10.1128/jvi.01879-16] [Citation(s) in RCA: 372] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 10/20/2016] [Indexed: 01/21/2023] Open
Abstract
Porcine circovirus-associated disease (PCVAD) is clinically manifested by postweaning multisystemic wasting syndrome (PMWS), respiratory and enteric disease, reproductive failure, and porcine dermatitis and nephropathy syndrome (PDNS). Porcine circovirus 2 (PCV2) is an essential component of PCVAD, although an etiologic role in PDNS is not well established. Here, a novel circovirus, designated porcine circovirus 3 (PCV3), was identified in sows that died acutely with PDNS-like clinical signs. The capsid and replicase proteins of PCV3 are only 37% and 55% identical to PCV2 and bat circoviruses, respectively. Aborted fetuses from sows with PDNS contained high levels of PCV3 (7.57 × 107 genome copies/ml), and no other viruses were detected by PCR and metagenomic sequencing. Immunohistochemistry (IHC) analysis of sow tissue samples identified PCV3 antigen in skin, kidney, lung, and lymph node samples localized in typical PDNS lesions, including necrotizing vasculitis, glomerulonephritis, granulomatous lymphadenitis, and bronchointerstitial pneumonia. Further study of archived PDNS tissue samples that were negative for PCV2 by IHC analysis identified 45 of 48 that were PCV3 positive by quantitative PCR (qPCR), with 60% of a subset also testing positive for PCV3 by IHC analysis. Analysis by qPCR of 271 porcine respiratory disease diagnostic submission samples identified 34 PCV3-positive cases (12.5%), and enzyme-linked immunosorbent assay detection of anti-PCV3 capsid antibodies in serum samples found that 46 (55%) of 83 samples tested were positive. These results suggest that PCV3 commonly circulates within U.S. swine and may play an etiologic role in reproductive failure and PDNS. Because of the high economic impact of PCV2, this novel circovirus warrants further studies to elucidate its significance and role in PCVAD. IMPORTANCE While porcine circovirus 2 (PCV2) was first identified in sporadic cases of postweaning multisystemic wasting syndrome in Canada in the early 1990s, an epidemic of severe systemic disease due to PCV2 spread worldwide in the ensuing decade. Despite being effectively controlled by commercial vaccines, PCV2 remains one of the most economically significant viruses of swine. Here, a novel porcine circovirus (PCV3) that is distantly related to known circoviruses was identified in sows with porcine dermatitis and nephropathy syndrome (PDNS) and reproductive failure. PCV2, which has previously been associated with these clinical presentations, was not identified. High levels of PCV3 nucleic acid were observed in aborted fetuses by quantitative PCR, and PCV3 antigen was localized in histologic lesions typical of PDNS in sows by immunohistochemistry (IHC) analysis. PCV3 was also identified in archival PDNS diagnostic samples that previously tested negative for PCV2 by IHC analysis. The emergence of PCV3 warrants further investigation.
Collapse
|
3
|
Binanti D, Mostegl MM, Weissenbacher-Lang C, Nedorost N, Weissenböck H. Detection of Pneumocystis infections by in situ hybridization in lung samples of Austrian pigs with interstitial pneumonia. Med Mycol 2014; 52:196-201. [PMID: 23859080 DOI: 10.3109/13693786.2013.809631] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Pneumocystis carinii f. sp. suis is a fungus multiplying in the respiratory tract of pigs which occasionally is associated with interstitial pneumonia. Identification of Pneumocystis in tissue samples is considered difficult and there are only scarce data on its occurrence in European pigs. This investigation presents an in situ hybridization (ISH) procedure for identification of Pneumocystis spp. in paraffin wax embedded tissue samples and its application for labeling the agent in lung samples of pigs with interstitial pneumonia. Thirty-two out of 100 lung samples from pigs on Austrian farms were identified as positive, five of them with multiple, 12 with moderate and 15 with few organisms but Grocott’s methenamine silver staining demonstrated that only 20 cases were unequivocally positive for Pneumocystis carinii. In addition to interstitial pneumonia Pneumocystis-positive pigs were more frequently affected with granulomatous pneumonia than Pneumocystis-negative pigs. Frequently concurrent infections with different viral or bacterial lung pathogens were noted but there was no positive correlation between Pneumocystis- and PCV-2-infections. With other infections, no clear-cut differences between Pneumocystis-positive and Pneumocystis-negative animals were found. This study shows that Pneumocystis infections occur frequently in Austrian pigs with interstitial pneumonia. It remains to be shown which are the factors triggering severe multiplication and whether infection with Pneumocystis alone is able to induce lung disease in pigs.
Collapse
|
4
|
Segalés J, Kekarainen T, Cortey M. The natural history of porcine circovirus type 2: From an inoffensive virus to a devastating swine disease? Vet Microbiol 2013; 165:13-20. [DOI: 10.1016/j.vetmic.2012.12.033] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 12/17/2012] [Accepted: 12/18/2012] [Indexed: 12/17/2022]
|
5
|
Experimental reproduction of porcine circovirus type 2 (PCV2)-associated enteritis in pigs infected with PCV2 alone or concurrently with Lawsonia intracellularis or Salmonella typhimurium. J Comp Pathol 2011; 145:261-70. [PMID: 21334002 DOI: 10.1016/j.jcpa.2010.12.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 09/27/2010] [Accepted: 12/27/2010] [Indexed: 11/22/2022]
Abstract
Porcine circovirus (PCV)-associated disease (PCVAD) has emerged to become one of the most economically important pig diseases globally. One of the less commonly recognized clinical manifestations of PCVAD is PCV2 type 2 (PCV2)-associated enteritis in growing pigs; however, experimental confirmation of the ability of PCV2 alone or PCV2 coinfection with other agent(s) to induce enteritis is lacking. In this study, 120 specific-pathogen-free (SPF) pigs were divided randomly into six groups: controls (negative control pigs), PCV2 (inoculated with PCV2), LAW (inoculated with Lawsonia intracellularis), SALM (inoculated with Salmonella typhimurium), PCV2-LAW (concurrently inoculated with PCV2 and Lawsonia intracellularis) and PCV2-SALM (concurrently inoculated with PCV2 and Salmonella typhimurium). One half of the pigs in each group were subject to necropsy examination 14 days postinoculation (dpi) and the remaining pigs were examined at 28 dpi. The average daily weight gain was not different (P>0.05) between groups. Individual pigs inoculated orally with PCV2 regardless of coinfection status (2/10 PCV2, 1/10 PCV2-LAW, 3/10 PCV2-SALM) developed PCVAD with diarrhoea and reduced weight gain or weight loss between 14 and 28 dpi. Those pigs had characteristic microscopic lesions in lymphoid and enteric tissues associated with abundant PCV2 antigen. Enteric lesions were characterized by necrosuppurative and proliferative enteritis with crypt elongation and epithelial hyperplasia in LAW and PCV2-LAW pigs by 14 dpi, ulcerative and necrosuppurative colitis in SALM and PCV2-SALM pigs by 14 dpi, and lymphohistiocytic enteritis with depletion of Peyer's patches in PCV2, PCV2-SALM and PCV2-LAW pigs by 28 dpi. To the authors' knowledge, this is the first report documenting that under experimental conditions, PCV2 can induce enteritis independently from other enteric pathogens and that oral challenge is a potentially important route and perhaps the natural route of PCV2 transmission in growing pigs.
Collapse
|
6
|
Sun SQ, Guo HC, Sun DH, Yin SH, Shang YJ, Cai XP, Liu XT. Development and validation of an ELISA using a protein encoded by ORF2 antigenic domain of porcine circovirus type 2. Virol J 2010; 7:274. [PMID: 20958981 PMCID: PMC2976745 DOI: 10.1186/1743-422x-7-274] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Accepted: 10/19/2010] [Indexed: 12/02/2022] Open
Abstract
Background The capsid protein (ORF2) is a major structural protein of porcine circovirus type 2 (PCV2). A simple and reliable diagnostic method based on ORF2 protein immunoreactivity would serve as a valuable diagnostic method for detecting serum antibodies to PCV2 and monitoring PCV infection. Here, we reported an indirect enzyme-linked immunosorbent assay (I-ELISA) by using an antigenic domain (113-147AA) of ORF2-encoded antigen, expressed in E. coli, for diagnosis of PCV infection. Results The ELISA was performed on 288 serum samples collected from different porcine herds and compared with an indirect immunofluorescent assay (IFA). In total, 262 of 288 samples were positive as indicated by both I-ELISA and IFA. The specificity and sensitivity of I-ELISA were 87.7% and 93.57%. Conclusions This ELISA is suitable for detection and discrimination of PCV2 infection in both SPF and farm antisera.
Collapse
Affiliation(s)
- Shi-Qi Sun
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, 730046, The People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
7
|
Borba MR, Sanches EMC, Corrêa AMR, Spanamberg A, de Souza Leal J, Soares MP, Guillot J, Driemeier D, Ferreiro L. Immunohistochemical and ultra-structural detection of Pneumocystis in wild boars (Sus scrofa) co-infected with porcine circovirus type 2 (PCV2) in Southern Brazil. Med Mycol 2010; 49:172-5. [PMID: 20807029 DOI: 10.3109/13693786.2010.510540] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Pneumocystis spp. are fungi that are able to infect a variety of host species and, occasionally, lead to severe pneumonia. Porcine circovirus type 2 (PCV2) is an important viral pathogen which affects both swine and wild boar herds worldwide. Co-infection between PCV2 and other pathogens has been reported, and the secondary immunodeficiency caused by the virus may predispose to these co-infections. In the present study, postmortem tissue samples obtained from wild boar herds in Southern Brazil were analyzed by histopathology, ultra-structural observation, and immunohistochemistry. Forty-seven out of seventy-eight (60%) wild boars showed clinical signs, gross, and histopathological lesions characteristic of infection by PCV2. Pneumocystis was detected by immunohistochemistry in 39 (50%) lungs and viral antigens of PCV2 were found in 29 (37.2%) samples. Concomitant presence of Pneumocystis and PCV2 were observed in 16 (20.5%) of the wild boars. Cystic and trophic forms of Pneumocystis were similar to previously described ultra-structural observations in other mammals.
Collapse
Affiliation(s)
- Mauro Riegert Borba
- Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
| | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Subcellular Immunolocalization of Porcine Circovirus Type 2 (PCV2) in Lymph Nodes from Pigs with Post-weaning Multisystemic Wasting Syndrome (PMWS). J Comp Pathol 2010; 142:291-9. [DOI: 10.1016/j.jcpa.2009.12.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 09/05/2009] [Accepted: 12/03/2009] [Indexed: 11/23/2022]
|
9
|
Klein S, Wendt M, Baumgärtner W, Wohlsein P. Systemic toxoplasmosis and concurrent porcine circovirus-2 infection in a pig. J Comp Pathol 2009; 142:228-34. [PMID: 19740479 PMCID: PMC7094381 DOI: 10.1016/j.jcpa.2009.08.155] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 06/30/2009] [Accepted: 08/10/2009] [Indexed: 02/03/2023]
Abstract
Systemic toxoplasmosis and concurrent infection with porcine circovirus-2 (PCV-2) was diagnosed in a fattening pig. Clinical examination of the herd showed that up to 30% of the pigs of this weight group suffered from severe respiratory signs including sneezing and coughing, with a mortality rate of up to 5%. Gross necropsy examination revealed severe interstitial pneumonia and generalized lymphadenopathy. On microscopical examination there was necrotizing inflammation of the lung, adrenal glands and lymph nodes, associated with lymphoid depletion, cytoplasmic basophilic botryoid inclusion bodies and protozoal microorganisms. Infection with Toxoplasma gondii was confirmed by immunohistochemistry (IHC). Polymerase chain reaction analysis, in-situ hybridization and IHC confirmed systemic PCV-2 infection. These findings, associated with the respiratory signs and lesions in lymphoid tissues, are characteristic for post-weaning multisystemic wasting syndrome (PMWS). In this case, immunosuppression by PCV-2 may have triggered systemic toxoplasmosis, or immune stimulation caused by coinfection with T. gondii may have caused extensive replication of PCV-2.
Collapse
Affiliation(s)
- S Klein
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | | | | | | |
Collapse
|
10
|
Szabó I, Bartus A, Harsányi Z, Lukács G, Molnár T, Stipkovits L. Prevalence of postweaning multisystemic wasting syndrome in pigs sired by 13 Hungarian Landrace boars. Vet Rec 2009; 165:143-6. [DOI: 10.1136/vr.165.5.143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- I. Szabó
- Pfizer Hungaria; Alkotás utca 53 1123 Budapest Hungary
| | | | | | - G. Lukács
- Füzesfarm 95, Pusztaszikszó 3390 Füzesabony Hungary
| | | | - L. Stipkovits
- Department of Pathology; State Veterinary Institute; Tábornok utca 2 1143 Budapest Hungary
| |
Collapse
|
11
|
Rodriguez-Cariñg C, SegalÉS J. Ultrastructural Findings in Lymph Nodes from Pigs Suffering from Naturally Occurring Postweaning Multisystemic Wasting Syndrome. Vet Pathol 2009; 46:729-35. [DOI: 10.1354/vp.08-vp-0141-r-fl] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aims of this study were to evaluate ultrastructural lesions in lymph nodes from postweaning multisystemic wasting syndrome (PMWS)-affected pigs and to correlate these alterations with detection of viral-like particles (VLPs). Samples of lymph nodes were taken from 4 PMWS-affected pigs and 2 healthy animals and processed by transmission electron microscopy. Significant ultrastructural alterations were only noted in PMWS-affected pigs, mainly in histiocytes and rarely in other cell types. Histiocytes showed severe swelling and proliferation of mitochondria, and proliferation and dilation of rough endoplasmic reticulum and Golgi complex. Infected histiocytes contained large numbers of intracytoplasmic inclusion (ICI) bodies with VLPs; some histiocytes also had intranuclear inclusions (INIs). Small inclusions were surrounded by double membrane, with a granular appearance or containing paracrystalline arrays; icosahedral VLPs were 8–17 nm in diameter. Large ICIs were double-membrane bounded or not and contained VLPs usually forming paracrystalline arrays. ICIs were often found next to mitochondria with severe swelling, and also inside them. INIs were not surrounded by membranes and contained virions of 10–13 nm diameter. Lymphocyte depletion was a striking finding of lymph nodes from PMWS-affected pigs. The inclusion bodies containing VLPs referred to in the present study should be classified as viral factories, suggesting that viral replication is probably a frequent event in macrophages, in which mitochondria might play a role.
Collapse
Affiliation(s)
- C. Rodriguez-Cariñg
- Departament de Sanitat i Anatomia Animals, Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autonoma de Barcelona, Bellaterra, Barcelona, Spain
| | - J. SegalÉS
- Departament de Sanitat i Anatomia Animals, Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autonoma de Barcelona, Bellaterra, Barcelona, Spain
| |
Collapse
|
12
|
Cságola A, Kiss I, Tuboly T. Detection and analysis of porcine circovirus type 1 in Hungarian wild boars: short communication. Acta Vet Hung 2008; 56:139-44. [PMID: 18401965 DOI: 10.1556/avet.56.2008.1.15] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Porcine circovirus type 1 (PCV1) is considered to be a non-pathogenic virus detected in cell cultures, vaccines or products used for cell culture preparations, all of them of porcine origin. Serological evidence and genetic studies suggested that PCV1 was widespread in domestic pigs. The presence of PCV1 in wild boars in Germany was also described using serological methods. This paper reports the first detection of PCV1 in Hungarian wild boars. Samples were collected at slaughterhouses and processed for polymerase chain reactions. The complete genome of PCV1 detected in the samples was determined and compared with the available PCV1 sequences of the GenBank database. The genomes formed two distinct clusters with minimum differences, where the Hungarian wild boar PCV1 (WB-H8) grouped together with genomes originating from domestic swine from China and Australia and with a genome detected in a porcine pepsin product.
Collapse
Affiliation(s)
- Attila Cságola
- 1 Szent István University Department of Microbiology and Infectious Diseases, Faculty of Veterinary Science H-1143 Budapest Hungária krt. 23-25 Hungary
| | - István Kiss
- 2 Central Agricultural Office Department of Microbiology, Veterinary Diagnostic Directorate Debrecen Hungary
| | - Tamás Tuboly
- 1 Szent István University Department of Microbiology and Infectious Diseases, Faculty of Veterinary Science H-1143 Budapest Hungária krt. 23-25 Hungary
| |
Collapse
|
13
|
O'Dea MA, Hughes AP, Davies LJ, Muhling J, Buddle R, Wilcox GE. Thermal stability of porcine circovirus type 2 in cell culture. J Virol Methods 2008; 147:61-6. [PMID: 17889378 DOI: 10.1016/j.jviromet.2007.07.029] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Revised: 07/25/2007] [Accepted: 07/30/2007] [Indexed: 10/22/2022]
Abstract
International trade in pig meat has resulted in some countries placing restrictions on the importation of pig meat, with requirements for cooking of imported meat to destroy viral agents. This study investigated the in vitro resistance of an Australian strain of porcine circovirus type 2 (PCV2), the causative agent of post-weaning multisystemic wasting syndrome (PMWS), to heat treatment. The viability of the virus in cell cultures was determined by a combination of reverse transcriptase polymerase chain reaction (RT-PCR) to detect viral transcripts, and immunohistochemistry (IHC) to visualize viral capsid antigen. PCV2 retained infectivity when heated at 75 degrees C for 15 min but was inactivated by heating at 80 degrees C and above for 15 min. The results provide important information on the thermal tolerance of PCV2, which can be taken into account in risk assessments for trade in pig meat and porcine-derived biological products.
Collapse
Affiliation(s)
- Mark A O'Dea
- School of Veterinary and Biomedical Sciences, Division of Health Sciences, Murdoch University, Murdoch 6150, Western Australia, Australia.
| | | | | | | | | | | |
Collapse
|
14
|
TAKAHASHI M, SEIMIYA YM, SEKI Y, YAMADA M. A Piglet with Concurrent Polioencephalomyelitis due to Porcine Teschovirus and Postweaning Multisystemic Wasting Syndrome. J Vet Med Sci 2008; 70:497-500. [DOI: 10.1292/jvms.70.497] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Maki TAKAHASHI
- Iwate Prefecture Central Livestock Hygiene Service Center
| | | | - Yoshihisa SEKI
- Iwate Prefecture Central Livestock Hygiene Service Center
| | | |
Collapse
|
15
|
de Castro AMMG, Cortez A, Heinemann MB, Brandão PE, Richtzenhain LJ. Molecular diversity of Brazilian strains of porcine circovirus type 2 (PCV-2). Res Vet Sci 2007; 85:197-200. [PMID: 17976668 DOI: 10.1016/j.rvsc.2007.07.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Revised: 07/13/2007] [Accepted: 07/16/2007] [Indexed: 11/26/2022]
Abstract
Porcine circovirus 2 (PCV-2) is associated with a broad range of syndromes. In this study, eight pig tissue samples from two Brazilian states were analyzed using six PCR primer pairs amplifying a 1705-bp fragment of the PCV-2 genome. The NJ distance-based method was used for the phylogenetic analysis with the eight field strains herein, 15 GenBank sequences and using PCV-1 as an out-group. This yielded two major clusters (A and B) for this viral species, with the Brazilian strains segregating with European and Asian sequences. Nucleotide identity was 99.7 to 100% among the sequences. This information can be used in further studies of pathogenesis related to PCV-2 in Brazil.
Collapse
|
16
|
Castro AD, Cortez A, Heinemann M, Brandão P, Richtzenhain L. CIRCOVÍRUS SUÍNO TIPO 2 (PCV-2). ARQUIVOS DO INSTITUTO BIOLÓGICO 2007. [DOI: 10.1590/1808-1657v74p2812007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
Abstract
RESUMO O Circovírus suíno-2 (Porcine circovirus type 2 – PCV-2) é um vírus não envelopado, apresenta simetria icosaédrica e mede de 15 a 17 nm de diâmetro. É o menor vírus animal descrito e está relacionado a várias síndromes que acometem suínos, responsável por perdas econômicas nas granjas. A alta variabilidade da região do genoma que codifica as proteínas estruturais associada às co-infecções, dificulta o seu diagnóstico e sua prevenção.
Collapse
|
17
|
Sanches EMC, Pescador C, Rozza D, Spanamberg A, Borba MR, Ravazzolo AP, Driemeier D, Guillot J, Ferreiro L. Detection ofPneumocystisspp. in lung samples from pigs in Brazil. Med Mycol 2007; 45:395-9. [PMID: 17654265 DOI: 10.1080/13693780701385876] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
The genus Pneumocystis is composed of opportunistic fungi currently considered as specific pulmonary pathogens in humans and other mammals. In pigs, Pneumocystis pneumonia (PcP) could create significant economical losses due to its detrimental effects on growth, food conversion, and carcass/viscera condemnation. This study revealed that Pneumocystis organisms could be detected by Grocott's staining or immunohistochemistry in 36.9% of 564 slaughtered pigs from two geographic regions of Brazil. The prevalence of positive cases was 39.9% and 33.9% in pigs slaughtered in Rio Grande do Sul (RS) and Mato Grosso (MT) states, respectively. Among the positive cases in RS, Pneumocystis organisms were observed in 41.9% of 33 histologically normal lungs, and in 58.0% of lungs presenting with histological lesions. In contrast, the prevalence in MT in normal and abnormal lungs was 36.3% and 63.5%, respectively. Major histopathological findings in lungs of infected animals were bronchointerstitial pneumonia (47.6%), suggestive of enzootic pneumonia, and interstitial pneumonia (37.9%), compatible with PcP. The results of this survey strengthened the interest of detecting fungal pathogens, in addition to other infectious agents, and evaluating their financial impact on Brazilian pig industry. Preventive and/or therapeutic strategies should be developed in order to minimize the incidence of respiratory fungal infections in pigs and associated economic losses.
Collapse
Affiliation(s)
- E M Cavallini Sanches
- Sections of Veterinary Mycology, Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Jensen TK, Vigre H, Svensmark B, Bille-Hansen V. Distinction between porcine circovirus type 2 enteritis and porcine proliferative enteropathy caused by Lawsonia intracellularis. J Comp Pathol 2006; 135:176-82. [PMID: 17070535 DOI: 10.1016/j.jcpa.2006.08.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Accepted: 08/14/2006] [Indexed: 10/24/2022]
Abstract
The presence of porcine circovirus type 2 (PCV2) was studied immunohistochemically in formalin-fixed, paraffin wax-embedded samples of intestinal tissue from 80 pigs with a clinical history suggestive of Lawsonia intracellularis-associated diarrhoea. Histopathologically, enteritis of varying intensity was diagnosed in 64 of the pigs. Of these 64 animals, 34 (18%) were infected with both PCV2 and L. intracellularis. Of the remaining 30 cases of enteritis, 23 (77%) were attributed to PCV2 infection alone. The PCV2-associated enteritis cases showed necrotizing ileitis and colitis, indistinguishable macroscopically from proliferative enteritis (PE) due to L. intracellularis. Histopathologically, L. intracellularis-positive intestines showed adenomatous proliferation of crypt enterocytes, whereas PCV2 enteritis was characterized by histiocytosis of varying intensity, with PCV2-positive cells in the submucosa, lamina propria and crypt epithelium, as well as in the lymphoid tissue of the ileum and colon. Multinucleated giant cells, however, were seen in both infections. PCV2 was about three times more likely to be detected in L. intracellularis-negative than in L. intracellularis-positive samples (P<0.001). There was no association between PCV2 and other intestinal bacterial pathogens. The study demonstrated that PCV2 enteritis should be borne in mind in the differential diagnosis of L. intracellularis infection in pigs aged 2-4 months with a clinical history of diarrhoea.
Collapse
Affiliation(s)
- T K Jensen
- Danish Institute for Food and Veterinary Research, Bülowsvej 27, DK-1790 Copenhagen, Denmark.
| | | | | | | |
Collapse
|
19
|
Murakami S, Ogawa A, Kinoshita T, Matsumoto A, Ito N, Nakane T. Occurrence of Swine Salmonellosis in Postweaning Multisystemic Wasting Syndrome (PMWS) Affected Pigs Concurrently Infected with Porcine Reproduction and Respiratory Syndrome Virus (PRRSV). J Vet Med Sci 2006; 68:387-91. [PMID: 16679733 DOI: 10.1292/jvms.68.387] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Fourteen diseased pigs from four farms in which there had been an outbreak of salmonellosis were investigated. Granulomatous inflammation with depletion of lymphocytes was observed in the swollen lymph nodes in these pigs. Antigens to porcine circovirus type 2 (PCV2) were immunolabeled in the lesions along with detection of viral DNA as PCV2 by polymerase chain reaction (PCR). In addition, antigens to porcine reproductive respiratory syndrome virus (PRRSV) were immunodetected in the lungs and Salmonella Choleraesuis was isolated from the affected pigs. The nine salmonellosis affected pigs, five (55.6%) with salmonellosis and PMWS concurrently infected with PRRSV were much higher than those infected with salmonellosis and PMWS (22.2%) or with salmonellosis and PPPRV (22.2%).
Collapse
|
20
|
Cságola A, Kecskeméti S, Kardos G, Kiss I, Tuboly T. Genetic characterization of type 2 porcine circoviruses detected in Hungarian wild boars. Arch Virol 2005; 151:495-507. [PMID: 16328152 DOI: 10.1007/s00705-005-0639-1] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2005] [Accepted: 08/16/2005] [Indexed: 11/24/2022]
Abstract
Porcine circoviruses (PCV) are present in pigs worldwide; they are grouped into two types: PCV1 comprising non-pathogenic viruses and PCV2 responsible for several clinical manifestations. Both types are frequently detected in domestic pigs, the prevalence and role of PCV in wild boars however, is not well studied. During the years 2002-2003 over 2000 organ samples of Hungarian wild boars were collected, grouped and samples from 307 different animals were tested by polymerase chain reaction for the presence of PCV. 35.5% of the wild boars were positive for one or both PCV types and PCV2 was detected in 20.5% of the animals. The PCV2 viruses were divided into 7 groups (WB-H1-7) based on sequencing data and genomes representing these groups were sequenced completely. The wild boar PCV2 groups were distributed evenly in the geographical region, regardless of the time and place of collection. The phylogenetic analysis of the PCV2 sequences of wild boar and domestic pig origin showed the possibility of an epidemiological link between wild boar and domestic pig infections. Interestingly, the complete nucleotide sequence of the viruses and the predicted amino acid sequence of the replication associated protein (ORF1) grouped the viruses similarly, whereas the capsid protein (ORF2) comparisons revealed different relations among the groups, suggesting the possibility of genomic recombination in PCV2.
Collapse
Affiliation(s)
- A Cságola
- Department of Microbiology and Infectious Diseases, Szent István University, Faculty of Veterinary Science, Budapest, Hungary
| | | | | | | | | |
Collapse
|
21
|
França TDN, Peixoto PV, Brito MF, Morés N, Zanella J, Driemeier D. Surto de Circovirose (Síndrome Definhante Multissistêmica de Suínos Desmamados) no estado do Rio de Janeiro. PESQUISA VETERINARIA BRASILEIRA 2005. [DOI: 10.1590/s0100-736x2005000100009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Descreve-se o primeiro surto de Síndrome Definhante Multissistêmica de Suínos Desmamados (SDMSD) na Região Sudeste do Brasil, no estado do Rio de Janeiro. A enfermidade que afetou principalmente suínos desmamados com idade em torno de 4 meses, levou a morte pelo menos 14 animais. A granja onde o surto ocorreu, tinha péssimas condições sanitárias e de manejo. Clinicamente, a doença caracterizou-se por má condição corporal, pouco desenvolvimento, tosse, taquipnéia, dispnéia, diarréia, ataxia, tremores após estímulo, decúbito e convulsões, com evolução aguda a subaguda. À necropsia, os achados mais importantes foram um aumento de volume de linfonodos e pulmões não-colapsados, com áreas consolidadas, principalmente nos lobos craniais e porção anterior dos lobos médios. O exame histológico revelou, com maior freqüência, infiltração linfo-histiocítica com células sinciciais em linfonodos, baço, placas de Peyer, rim, pulmão e fígado, depleção ou hiperplasia linfóide, bem como pneumonia bronco-intersticial linfo-histiocitária e áreas de broncopneumonia secundária. O diagnóstico firmou-se pela observação dos sintomas e das lesões histológicas típicas e foi confirmado por exame imunohistoquímico e PCR. O estudo teve por objetivo caracterizar os aspectos epidemiológico e clínico-patológico desse surto, já que a mesma tem causado grandes perdas econômicas, diretas ou indiretas, à suinocultura mundial.
Collapse
|
22
|
Wang C, Huang TS, Huang CC, Tu C, Jong MH, Lin SY, Lai SS. Characterization of porcine circovirus type 2 in Taiwan. J Vet Med Sci 2004; 66:469-75. [PMID: 15187354 DOI: 10.1292/jvms.66.469] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In an effort to understand the genetic diversity of porcine circovirus type 2 (PCV2) and the prevalence of PCV2 infection in Taiwanese herds, we have sequenced the complete genomes from PCV2-infected specimens and individually measured the antibody titer against PCV2 from pigs reared in Taiwan between the years 2000 and 2002. A total of 623 specimens originating from pigs displaying varied clinical signs were screened with the polymerase chain reaction (PCR). Results showed that 309 pigs (49.6%) tested positive for PCV2. Eight of the positive specimens were used for the amplification of the complete viral genome. Sequence comparison of the complete genomes indicated that the 8 Taiwanese PCV2 isolates shared 95-99% similarity. Phylogenetic analysis of all 40 PCV2 isolates from North America, Europe, Asia and Taiwan revealed that those isolates were grouped together in one large group containing two minor subgroups. The Taiwanese PCV2 isolates were classified into the two minor subgroups. The prevalence of serum antibodies to PCV2 in pigs was investigated, and results showed that approximately 83.5% of the pigs in Taiwan were seropositive. Finishing pigs possess the highest titers of antibodies, while 9-week-old pigs contained the lowest titers for specific antibodies. Our results suggest that PCV2 infections have become common in Taiwanese pig farms.
Collapse
Affiliation(s)
- Chun Wang
- Department of Hog Cholera Research, National Institute for Animal Health, Council of Agriculture, Taipei, Taiwan
| | | | | | | | | | | | | |
Collapse
|
23
|
Toplak I, Grom J, Hostnik P, Barlic-Maganja D. Phylogenetic analysis of type 2 porcine circoviruses identified in wild boar in Slovenia. Vet Rec 2004; 155:178-80. [PMID: 15357380 DOI: 10.1136/vr.155.6.178] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- I Toplak
- Department of Virology, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1115, Slovenia
| | | | | | | |
Collapse
|
24
|
Castro AMMG, Cortez A, Ruiz VLA, Leomil H, Moreno AM, Doto DS, Richtzenhain LJ. Detection and differentiation of porcine circoviruses in Brazilian pigs. Vet Rec 2004; 154:728-9. [PMID: 15214518 DOI: 10.1136/vr.154.23.728] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- A M M G Castro
- Department of Preventive Veterinary Medicine and Animal Health, University of São Paulo, São Paulo, 05508-900, Brazil
| | | | | | | | | | | | | |
Collapse
|
25
|
Darwich L, Pié S, Rovira A, Segalés J, Domingo M, Oswald IP, Mateu E. Cytokine mRNA expression profiles in lymphoid tissues of pigs naturally affected by postweaning multisystemic wasting syndrome. J Gen Virol 2003; 84:2117-2125. [PMID: 12867643 DOI: 10.1099/vir.0.19124-0] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Fifteen 8-week-old conventional pigs were selected from a farm where pigs were suffering from postweaning multisystemic wasting syndrome (PMWS). Ten of the animals were diseased pigs showing typical signs of PMWS (wasting and respiratory disorders) and positive for infection with porcine circovirus type 2 (PCV2), and the other five animals selected as controls were pen-mate, apparently healthy pigs. Blood samples and lymphoid tissues were taken from each animal for haematological, serological and histopathological studies. Also, cytokine mRNA expression of IL-1beta, IL-2, IL-4, IL-8, IL-10, IL-12p40 and IFN-gamma from inguinal and bronchial lymph nodes, tonsils, spleen and thymus was determined by semi-quantitative RT-PCR. Pigs suffering from PMWS showed severe alterations of haematological parameters such as anaemia, lymphopenia with decrease of CD8(+) and IgM(+) cells, monocytosis and neutrophilia. Also, extensive lymphocyte depletion and altered cytokine mRNA expression patterns were seen in most of the examined lymphoid organs. Those cytokine mRNA alterations were characterized by an overexpression of IL-10 mRNA in thymus and IFN-gamma mRNA in tonsils, and by decreases in the mRNA expression of several cytokines as IL-2 and IL-12p40 in the spleen, IL-4 in tonsils, and IFN-gamma, IL-10, IL-12p40 and IL-4 in inguinal lymph nodes. Also, the IL-10 mRNA overexpression was histologically associated with the thymic depletion and atrophy observed in PMWS pigs. In conclusion, the cytokine mRNA imbalance, specially the increased mRNA levels of IL-10 in the thymus, jointly with the histopathological and haematological disorders, are highly indicative of a T-cell immunosuppression, enhancing the notion that the immune system of PMWS-affected pigs is severely impaired.
Collapse
Affiliation(s)
- Laila Darwich
- Centre de Recerca en Sanitat Animal (CReSA), Departament de Sanitat i d'Anatomia Animals (Unitat de Malalties Infeccioses), Facultat de Veterinària, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Sandrine Pié
- Institut National de Recherche Agronomique, Laboratoire de Pharmacologie et Toxicologie, 180 chemin de Tournefeuille, BP3, 31931 Toulouse, France
| | - Albert Rovira
- Centre de Recerca en Sanitat Animal (CReSA), Departament de Sanitat i d'Anatomia Animals (Unitat de Malalties Infeccioses), Facultat de Veterinària, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Joaquim Segalés
- Centre de Recerca en Sanitat Animal (CReSA), Departament de Sanitat i d'Anatomia Animals (Unitat de Malalties Infeccioses), Facultat de Veterinària, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Mariano Domingo
- Centre de Recerca en Sanitat Animal (CReSA), Departament de Sanitat i d'Anatomia Animals (Unitat de Malalties Infeccioses), Facultat de Veterinària, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Isabelle P Oswald
- Institut National de Recherche Agronomique, Laboratoire de Pharmacologie et Toxicologie, 180 chemin de Tournefeuille, BP3, 31931 Toulouse, France
| | - Enric Mateu
- Centre de Recerca en Sanitat Animal (CReSA), Departament de Sanitat i d'Anatomia Animals (Unitat de Malalties Infeccioses), Facultat de Veterinària, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| |
Collapse
|
26
|
Yang JS, Song DS, Kim SY, Lyoo KS, Park BK. Detection of porcine circovirus type 2 in feces of pigs with or without enteric disease by polymerase chain reaction. J Vet Diagn Invest 2003; 15:369-73. [PMID: 12918820 DOI: 10.1177/104063870301500412] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
To establish the sensitive polymerase chain reaction(PCR) method and detect porcine circovirus type 2 (PCV2) from intestines and feces of commercial swine herds with or without enteric disease, intestinal samples from 68 pigs and 29 fecal samples from commercial swine farms were collected. A primer set, forward primer 5'-GAAGAATGGAAGAAGCGG-3' and reverse primer 5'-CTCACAGCAGTAGACAGGT-3', could detect the virus at a concentration as low as 2 infectious virions per milliliter under controlled conditions using PK-15 cell-adapted PCV2. The genomic nucleotide sequences of open reading frame 1 (ORF1) PCR products from fecal samples were found to have complete homology with other PCV2s deposited in the GenBank database. Transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhea virus (PEDV) as the other enteric pathogens were also investigated by performing duplex reverse transcription-PCR (RT-PCR). Among 63 pigs with clinical enteric disease, 18 PCV2s (14 from intestines and 4 from feces), 7 TGEVs from intestines, and 18 PEDVs (14 from intestines and 4 from feces) were detected by PCR and the duplex RT-PCR. In 34 pigs (14 from intestines and 20 from feces) without clinical enteric disease, only PCV2 was detected in 19 pigs (3 from intestines and 16 from feces). Both PEDV and PCV2 were found in 6 pigs with clinical enteric disease. Among 15 PCV2 samples that were PCR-positive, 4 were culture-positive at passage level 3 in PK-15 cells. These results reveal that PCV2 is shed through the feces of pigs without clinical enteric disease, which suggests the potentiality of the fecal-oral transmission of PCV2 in feces.
Collapse
Affiliation(s)
- Jeong S Yang
- Virology Laboratory, Department of Veterinary Medicine, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Suwon 441-744, Korea
| | | | | | | | | |
Collapse
|
27
|
Pogranichniy RM, Yoon KJ, Harms PA, Sorden SD, Daniels M. Case-control study on the association of porcine circovirus type 2 and other swine viral pathogens with postweaning multisystemic wasting syndrome. J Vet Diagn Invest 2002; 14:449-56. [PMID: 12423025 DOI: 10.1177/104063870201400601] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
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.
Collapse
Affiliation(s)
- Roman M Pogranichniy
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames 50011, USA
| | | | | | | | | |
Collapse
|
28
|
Kiatipattanasakul-Banlunara W, Tantilertcharoen R, Suzuki K, Albarenque SM, Thanawongnuwech R, Nakayama H, Doi K. Detection of porcine circovirus 2 (PCV-2) DNA by nested PCR from formalin-fixed tissues of post-weaning multisystemic wasting syndrome (PMWS) pigs in Thailand. J Vet Med Sci 2002; 64:449-52. [PMID: 12069080 DOI: 10.1292/jvms.64.449] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
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.
Collapse
|
29
|
Nawagitgul P, Harms PA, Morozov I, Thacker BJ, Sorden SD, Lekcharoensuk C, Paul PS. Modified indirect porcine circovirus (PCV) type 2-based and recombinant capsid protein (ORF2)-based enzyme-linked immunosorbent assays for detection of antibodies to PCV. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2002; 9:33-40. [PMID: 11777826 PMCID: PMC119869 DOI: 10.1128/cdli.9.1.33-40.2002] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Postweaning multisystemic wasting syndrome of swine associated with porcine circovirus (PCV) is a recently reported and economically important disease. Simple and reliable diagnostic methods are needed for detecting antibodies to PCV type 2 (PCV2) for monitoring of PCV infection. Here, we report the development of two modified indirect enzyme-linked immunosorbent assays (ELISAs): a PCV2 ELISA based on cell-culture-propagated PCV2 and an ORF2 ELISA based on recombinant major capsid protein. PCV2 and ORF2 ELISA detected antibodies to PCV2 and the capsid protein, respectively, in sera from pigs experimentally infected with PCV2 as early as 14 and 21 days postinoculation (dpi). The kinetics of the antibody response to PCV2 and the major capsid protein were similar. Repeatability tests revealed that the coefficients of variation of positive sera within and between runs for both assays were less than 30%. To validate the assays, PCV2 and ORF2 ELISAs were performed with 783 serum samples of young and adult pigs collected from different herds in the Midwestern United States and compared with an indirect immunofluorescent assay (IIF). Six out of 60 samples collected from nursery and growing pigs in 1987 were positive by both ELISA and IIF. Compared with IIF, the diagnostic sensitivity, specificity, and accuracy of PCV2 and ORF2 ELISAs were similar (>90%). The tests showed no cross-reactivity with antibodies to porcine parvovirus and porcine reproductive and respiratory syndrome virus. There was good agreement between the two ELISAs and between the ELISAs and IIF. The availability of the two ELISAs should accelerate our understanding of the host immune response to PCV2 and facilitate the development of prevention and control strategies by elucidating the ecology of PCV2 within swine populations.
Collapse
Affiliation(s)
- Porntippa Nawagitgul
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA 50011, USA
| | | | | | | | | | | | | |
Collapse
|
30
|
Shibahara T, Sato K, Ishikawa Y, Kadota K. Porcine circovirus induces B lymphocyte depletion in pigs with wasting disease syndrome. J Vet Med Sci 2000; 62:1125-31. [PMID: 11129853 DOI: 10.1292/jvms.62.1125] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To disclose the mechanism of cellular injury following porcine circovirus (PCV) infection, 12 pigs were examined by the terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) method and immunohistochemistry. Histologically, the lymphoid tissues were characterized by marked apoptosis of lymphocytes, lymphocyte depletion, and macrophages and giant cells containing numerous inclusion bodies with or without apoptotic bodies. Immunohistochemically, there were many lysozyme-positive macrophages in the lymphoid follicles, while the number of CD79a-positive B lymphocytes was scanty. Apoptotic cells, which were proved to be TUNEL positive, revealed CD79a positivity. Although detectable mainly in the cytoplasm of macrophages, PCV antigens were found also in the nuclei of macrophages and apoptotic lymphocytes. Ultrastructurally, the presence of PCV virions was confirmed in apoptotic bodies phagocytosed by macrophages. These findings suggested that lymphocyte depletion with apoptotic death of B lymphocytes was caused by PCV, and that some of the inclusion bodies were phagolysosomes derived from the apoptosis. Thus, PCV may trigger the development of wasting disease syndrome by producing an immunocompromised state in pigs.
Collapse
Affiliation(s)
- T Shibahara
- Hokkaido Research Station, National Institute of Animal Health, Toyohira, Sapporo, Japan
| | | | | | | |
Collapse
|