Evidence of Porcine Circovirus Infection in Pigs with Wasting Disease Syndrome from 1985 to 1999 in Hokkaido, Japan

Journal of Veterinary Medical Science

Masanori KUBO¹  Yoshiharu ISHIKAWA³  Koichi KADOTA³  Tomoyuki SHIBAHARA³  Hiroshi KONDO²  Kenshi SATO⁴ 

[1] National Institute of Animal Health, 3-1-1 Kannondai, Tsukuba, Ibaraki 305-0856, Japan;Ishikari Livestock Hygiene Service Center, 3 Hitsujigaoka, Toyohira, Sapporo 062-0045, Japan;Hokkaido Research Station, National Institute of Animal Health, 4 Hitsujigaoka, Toyohira, Sapporo 062-0045, Japan;Hokkaido Research Station, National Institute of Animal Health, 4 Hitsujigaoka, Toyohira, Sapporo 062-0045, Japan and Tokachi Livestock Hygiene Service Center, 59-6 Kisen, Kawanishi, Obihiro 089-1182, Japan

关键词: epizootiological survey;    porcine;    porcine circovirus;    postweaning multisystemic wasting syndrome;   

DOI  :  10.1292/jvms.62.627

学科分类：兽医学

来源: Japanese Society of Veterinary Science

【 摘 要 】

References(28)Cited-By(18)An epizootiological survey with histopathological methods was conducted for porcine circovirus in 220 diseased pigs (1-200 days old) in 49 farms from 1985 to 1999. Histopathological lesions containing PCV antigen were detected mainly in the lymphoid tissues from 42 of 189 diseased pigs (22.2%) in 4 of 45 farms (8.9%) from 1990 to 1999. The rate of positive pigs gradually increased from 1997 onward and PCV infection was found in 50% of diseased pigs in 1999. Histopathologically, the lesions in the lymphoid tissues (including lymph nodes, Peyer's patches, tonsil and spleen) were highly correlated with the presence of numerous spherical basophilic intracytoplasmic inclusion bodies with PCV antigen, and consisted of lymphocellular depletion and infiltration of macrophages. Although most affected cells showed cytoplasmic reactivity for PCV, intranuclear antigen was also seen in the lymphocytes, macrophages and ileal epithelial cells. Ultrastructurally, macrophages and giant cells contained electron-dense, round to ovoid lysosomal bodies, in which there were concentric circle or paracrystalline arrays of small nonenveloped icosahedral viral particles, approximately 15-17 nm in diameter. Other consistent infectious agents were present in 90.5% of cases, and porcine reproductive and respiratory syndrome virus infection was in 52.4% of the cases with PCV. The histopathological findings suggested that PCV induced systemic immunosuppression in the infected pigs and made them more susceptible to infection of the organisms. Because of the presence of PCV antigens in the intestinal epithelium, feces may play a significant role in dissemination of PCV.

【 授权许可】

Unknown