Ultrastructural Identification of Circovirus in the Liver of Saffron Finch (Sicalis flaveola spp.)

• Published in: International journal of morphology 2011-06, Vol.29 (2), p.537-542
• Main Authors: Catroxo, M. H. B, Martins, A. M. C. R. P. F, Melo, N. A, Milanelo, L, Petrella, S, Fitorra, L. S, Petri, B. S. S
• Format: Article
• Language: English
• Subjects: ANATOMY & MORPHOLOGY
• ISSN: 0717-9502; 0717-9502
• DOI: 10.4067/S0717-95022011000200039

Circovirus are viral agents that cause disease in avian species. The main clinical symptoms of the disease are immunosuppression and, in young birds feather disorders. In neonates, the disease is known as "black spot" and characterized by abdominal enlargement, hepatobiliar congestion and failure to thrive. Also, it wasobserved in adult infected birds with other symptoms and clinical signs, such as enteritis, sinusitis, rhinitis, tracheitis, bronchopneumonia, myocarditis, nephritis, splenitis, dyspnea, anorexia, depression leading to high mortality. In April 2008, 317 saffron finch were apprehended during an illegal commercialization and were forwarded to the Wild Animals Recovery Center of the Tiete Ecological Park. Subsequently, 101 (31.66%) died and 20 of these were selected and sent to the Laboratory of Electron Microscopy, Biological Institute of São Paulo, Brazil to investigate possible etiological agents. After necropsy of these animals fragments of lung, liver and small intestine were processed using negative staining and resin embedding techniques. On the transmission electron microscopy, the negative staining technique allowed observation in 20 (100%) samples of liver suspension, a great number of particles with morphology similar to the circovirus, spherical, non-enveloped, isometric, characterized as "complete" and "empty ", measuring between 17 and 20 nm in diameter. By the resin embedding technique, oval or rounded viral intracytoplasmatic inclusion bodies, containing viral particles disposed in paracrystalline arrays or loose arrangements were observed in ultrathin sections on the 20 (100%) samples of liver suspension. This is the first report on the presence of circovirus in saffron finch (Sicalis flaveola spp.).