Screening of freshwater fish species for their susceptibility to a betanodavirus

Diseases of Aquatic Organisms

Toshihiro Nakai¹  Yasushi Okinaka¹  Kazumasa Uematsu¹  Ryo Furusawa¹ 

关键词: Betanodavirus;    Freshwater fish;    Model fish;    Experimental infection;    Medaka;    Rainbowfish;   

DOI  :  10.3354/dao01841

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Betanodaviruses, the causative agents of viral nervous necrosis in marine fish, have bipartite positive-sense RNA genomes. Because the genomes are the smallest and simplest among viruses, betanodaviruses have been well studied using a reversed genetics system as model viruses. However, studies of virus–host interactions have progressed slowly because permissive hosts for betanodaviruses (basically larvae and juveniles of marine fish) are only available for limited periods of the year and are not suitable for the construction of a genetic engineering system. To obtain a model fish species that are not subject to these problems, 21 freshwater fish species were injected intramuscularly with a betanodavirus (redspotted grouper nervous necrosis virus) and tested for their susceptibility to the virus. Based on their responses, the tested fish were classified into 3 groups: 4 susceptible fish, 10 less susceptible fish, and 7 resistant fish. The susceptible fish, celebes rainbowfish Telmatherina ladigesi, threadfin rainbowfish Iriatherina werneri, dwarf rainbowfish Melanotaenia praecox, and medaka Oryzias latipes, exhibited erratic swimming and eventually died within 10 d post-inoculation. The virus was specifically localized in the brains, spinal cords, and retinas of the infected fish, similar to the pattern of infection in naturally infected marine fish. We believe that these susceptible freshwater fish species could act as good host models for betanodavirus–fish interaction studies.

【 授权许可】

Unknown