An outbreak of VHSV (viral hemorrhagic septicemia virus) infection in farmed Japanese flounder Paralichthys olivaceus in Japan

Diseases of Aquatic Organisms

Taizou Nagano¹  Toyohiko Nishizawa¹  Tatsuya Kobayashi¹  Tadashi Isshiki¹  Teruo Miyazaki¹ 

关键词: Viral hemorrhagic septicemia;    Viral hemorrhagic septicemia virus;    Paralichthys olivaceus;    Japanese flounder;    Hirame;    Necrotizing myocarditis;   

DOI  :  10.3354/dao047087

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: A rhabdoviral disease occurred in farmed populations of market sized Japanese flounder (hirame) Paralichthys olivaceus in the Seto Inland Sea of Japan in 1996. The causative agent was identified as viral hemorrhagic septicemia virus(VHSV) based on morphological, immunological, and genetic analyses. Diseased fish that were artificially injected with a representative virus isolate showed the same pathological signs and high mortality as observed in the natural outbreak. This is thefirst report of an outbreak of VHSV infection in cultured fish in Japan. Clinical signs of diseased fish included dark body coloration, an expanded abdomen due to ascites, congested liver, splenomegaly, and a swollen kidney. Myocardial necrosis was mostprominent and accompanied by inflammatory reactions. Necrotic lesions also occurred in the liver, spleen and hematopoietic tissue, and were accompanied by circulatory disturbances due to cardiac failure. Hemorrhagic lesions did not always appear in thelateral musculature. Transmission electron microscopy revealed many rhabdovirus particles and associated inclusion bodies containing nucleocapsids in the necrotized myocardium. The histopathological findings indicated that the necrotizing myocarditiscould be considered a pathognomonic sign of VHSV infection in Japanese flounder.

【 授权许可】

Unknown