Diagnosis of post-weaning multisystemic wasting syndrome in pigs in Brazil caused by porcine circovirus type 2

This report describes the first preliminary characterization of porcine circovirus type 2 (PCV2) isolates from pigs affected with post-weaning multisystemic wasting syndrome (PMWS) in Brazil. Diseased pigs were examined at necropsy and by histopathology. Macroscopic and microscopic analyses revealed lesions reported to be typical of PMWS, which included, respectively, emaciation, enlargement of lymph nodes, thymus atrophy and interstitial pneumonia, and granulomatous lymphadenitis with syncytial cells, among others. Using nested polymerase chain reaction (PCR) or imunoperoxidase it was possible to detected DNA or antigen of PCV2, respectively. The PCR' s amplified fragment could be differentiated from PCV1 and PCV2 from one another by restriction fragment length polymorphism (RFLP) analysis. PCV2 DNA was detected in 70% (14/20) of samples of pigs with clinical signs and lesions associated with PMWS. This study shows that PCV2 is associated with lesions and symptoms indicative of PMWS in pigs. It is also shown that the Brazilian PCV2 isolates may have variation in their genome.

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Porcine circovirus type 2 and associated diseases in Romania — Short communication

Acta Veterinaria Hungarica ◽

10.1556/avet.55.2007.1.14 ◽

2007 ◽

Vol 55 (1) ◽

pp. 151-156 ◽

Cited By ~ 6

Author(s):

D. Cadar ◽

A. Cságola ◽

Á. Dán ◽

Z. Deim ◽

Marina Spînu ◽

...

Keyword(s):

Clinical Signs ◽

Porcine Circovirus Type ◽

Postweaning Multisystemic Wasting Syndrome ◽

Porcine Circovirus Type 2 ◽

Porcine Circovirus ◽

Serum Samples ◽

Associated Diseases ◽

Wasting Syndrome

Porcine circovirus type 2 (PCV2) has been demonstrated to be the causal agent for postweaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS). This report describes the first detection of PCV2 and associated diseases in a Romanian swine herd located in Transylvania. The clinical signs, pathological and histopathological changes observed in affected pigs were similar to those previously described for PDNS and PMWS. Polymerase chain reaction and in situ hybridisation were used for the detection of PCV2 nucleic acids from tissues and serum samples. Complete PCV2 genomes of both PMWS and PDNS cases were sequenced and analysed, and by comparing them with each other no genomic differences could be detected. The sequence analysis showed that the Romanian PCV2 was closely related to PCV2 identified in France and in Hungary.

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Experimental Reproduction of Postweaning Multisystemic Wasting Syndrome in Cesarean-Derived, Colostrum-Deprived Piglets Inoculated with Porcine Circovirus Type 2 (PCV2): Investigation of Quantitative PCV2 Distribution and Antibody Responses

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063870301500204 ◽

2003 ◽

Vol 15 (2) ◽

pp. 107-114 ◽

Cited By ~ 32

Author(s):

Y. Okuda ◽

M. Ono ◽

S. Yazawa ◽

I. Shibata

Keyword(s):

Clinical Signs ◽

Porcine Circovirus Type ◽

Postweaning Multisystemic Wasting Syndrome ◽

Porcine Circovirus Type 2 ◽

Porcine Circovirus ◽

Control Group ◽

Serum Samples ◽

Tissue Samples ◽

Wasting Syndrome

Sixteen cesarean-derived, colostrum-deprived piglets were inoculated intranasally with porcine circovirus type 2 (PCV2), originally isolated from a pig affected with postweaning multisystemic wasting syndrome (PMWS). At 1 day postinoculation (PI), 3 of the 5 piglets in the uninoculated control group were moved to the room of inoculated piglets for contact exposure. Porcine circovirus type 2 was detected by polymerase chain reaction (PCR) in swabs from inoculated piglets from 1 day PI and from contact piglets from 2 days after cohabitation. Porcine circovirus type 2 was also detected in all serum samples but not in control piglets 7 days PI. Until the end of study, PCV2 was detected in swabs and serum samples by PCR but not in the control piglets. One inoculated piglet died suddenly without clinical signs 19 days PI. Beginning at 14 days PI, 5 piglets, including 1 contact piglet, had clinical signs of depression, anorexia, and icterus, and 1 inoculated piglet died 21 days PI. Most of the piglets exhibiting the above clinical signs became moribund and were necropsied 21 and 28 days PI. In the piglets that showed clinical signs, gross lesions, including icterus of liver and hemorrhage in stomach, and typical histopathological lesions of PMWS, such as lymphoid depletion and basophilic intracytoplasmic inclusion bodies in lymph nodes and other tissues, were observed. Porcine circovirus type 2 was detected by PCR in all tissue samples except in those of the control piglets. Porcine circovirus type 2 was recovered from several tissue samples of the piglets necropsied until 35 days PI. In particular, PCV2 was recovered in high titer from most of the tissue samples of the piglets exhibiting clinical signs. Serum antibody against PCV2 was mostly detected in inoculated piglets and in contact piglets 14 and 21 days PI by an indirect fluorescence antibody test but was not detected in the piglets exhibiting clinical signs until 28 days PI. These results indicate that PCV2 was able to induce clinical PMWS in the absence of other swine pathogens and that there were significant differences in both the quantitative PCV2 distribution in tissues and the antibody response between the piglets that were infected and developed PMWS and those that were infected but remained healthy.

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Postweaning multisystemic wasting syndrome (pmws) in pigs in Croatia: Detection and characterisation of porcine circovirus type 2 (pcv2)

Acta Veterinaria Hungarica ◽

10.1556/avet.53.2005.3.11 ◽

2005 ◽

Vol 53 (3) ◽

pp. 385-396 ◽

Cited By ~ 6

Author(s):

Z. Lipej ◽

J. Segalés ◽

I. Toplak ◽

B. Šoštarić ◽

Besi Roić ◽

...

Keyword(s):

Clinical Signs ◽

Porcine Circovirus Type ◽

Postweaning Multisystemic Wasting Syndrome ◽

Porcine Circovirus Type 2 ◽

Porcine Circovirus ◽

Wasting Syndrome ◽

The United Kingdom ◽

Close Relationship

The objective of this study was to characterise porcine circovirus type 2 (PCV2) from pigs with naturally occurring postweaning multisystemic wasting syndrome (PMWS) in Croatia, and to determine the epizootiological, clinical and pathomorphological features of the disease. During a systematic health monitoring programme conducted in the period from January 2002 to June 2003, PMWS was suspected on eight different pig-producing farms in Croatia. The diagnosis of PMWS met all three key criteria: the presence of compatible clinical signs, the presence of the characteristic microscopic lymphoid lesions, and the detection of PCV2 within the lesions by polymerase chain reaction (PCR) and by in situ hybridisation (ISH). Moreover, PCV2 DNA from swine tissues was extracted and sequenced. The phylogenetic analysis of 4 Croatian PCV2 strains showed close relationship to PCV2 strains isolated in Slovenia, France, the Netherlands, the United Kingdom, China and Hungary. PCV2 was also demonstrated by electron microscopy in the lymph node of an affected animal. This is the first demonstration of PMWS in Croatia based on all scientifically accepted diagnostic criteria.

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Porcine Circovirus Type 2-Associated Cerebellar Vasculitis in Postweaning Multisystemic Wasting Syndrome (PMWS)-Affected Pigs

Veterinary Pathology ◽

10.1354/vp.44-5-621 ◽

2007 ◽

Vol 44 (5) ◽

pp. 621-634 ◽

Cited By ~ 35

Author(s):

F. A. Seeliger ◽

M. L. Brügmann ◽

L. Kruger ◽

I. Greiser-Wilke ◽

J. Verspohl ◽

...

Keyword(s):

Endothelial Cells ◽

Clinical Signs ◽

Porcine Circovirus Type ◽

Postweaning Multisystemic Wasting Syndrome ◽

Porcine Circovirus Type 2 ◽

Growing Pigs ◽

Vascular Lesions ◽

Porcine Circovirus ◽

Wasting Syndrome

Porcine circovirus type 2 (PCV2) is associated with several syndromes in growing pigs, including postweaning multisystemic wasting syndrome and porcine dermatitis and nephropathy syndrome. In the present study, a previously undescribed neurovascular disorder associated with a PCV2 infection is described. Sixteen pigs showed clinical signs of wasting and neurologic deficits. Acute hemorrhages and edema of cerebellar meninges and parenchyma due to a necrotizing vasculitis resulted in degeneration and necrosis of the gray and white matter. Few to numerous PCV2 DNA and antigen-bearing endothelial cells were detected in affected areas of the brain using in situ hybridization and immunohistochemistry. Conventional histochemical stains, as well as the detection of caspase 3 activity and DNA strand breaks by the terminal transferase dUTP nick end labeling assay, showed numerous apoptotic endothelial cells in the vascular lesions observed. Sequencing of various brain-derived PCV2-specific amplicons revealed a strong identity between different isolates and an 89 to 100% identity to previous isolates. The phylogenetic tree showed that there was no clustering of isolates correlating to clinical signs or geographic distribution. This previously undescribed PCV2-associated neurologic disease has features of both postweaning multisystemic wasting syndrome and, to a lesser extent, porcine dermatitis and nephropathy syndrome. The available evidence suggests that direct virus-induced apoptosis of endothelial cells plays a role in the pathogenesis of this unusual PCV2-associated cerebellar vasculitis.

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