Abstract

Zebra fish (Danio rerio) are tropical fish utilized for genetic and developmental studies. Currently, there are no viral disease models that employ this organism. To study the roles that genes play in piscine viral disease pathogenesis, we developed an infectious disease model for zebra fish utilizing spring virema of carp virus (SVCV). After spawning a wild type strain of zebra fish, 160 were reared to adults and were moved into an aquatic biohazard level-3 facility. Replicate groups of 10 fish were exposed, via immersion, to varying concentrations of SVCV, which had been grown and titered in epithelioma papulosum cyprini cells. Clinical signs became evident approximately seven days after viral exposure. In zebrafish, SVCV produces anorexia, listlessness, multifocal epidermal petechial hemorrhages and death, similar to that observed in the naive cyprinid species in Europe and Asia. Viral isolation and PCR assay of tissue from infected fish revealed high levels of virus. Histopathologic lesions include multifocal hepatic necrosis, and melanomacrophage proliferation in the gills, liver, and kidneys. The future use of this disease model with varying stocks of mutant zebra fish will be of assistance in studying the genetic basis of viral pathogenesis and potential genetic differences.

Acknowledgements

Supported by NIH grant T32 RR07019.