VIRAL HEMATOPOIETIC NECROSIS IN AN ANGELFISH {PTEROPHYLLUM SCALARE)

Abstract

Sudden death of a juvenile angelfish (Pterophyllum scalare) was caused by massive necrosis of the viscera. Intact cells in affected organs were enlarged and contained cytoplasmic inclusion bodies, which displaced the nuclei peripherally. Transmission electron microscopy of infected cells individually selected from histopathology slides identified the inclusions as icosahedral virus particles 110-120 nm in diameter. The morphology of the particles was suggestive of an iridovirus, but fresh tissue was not available for additional studies. A subsequent attempt to isolate this virus during a mass mortality of angelfish obtained from the same source as the index case was unsuccessful.