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Sequential tests for infectious hematopoietic necrosis virus in individuals and populations of sockeye salmon

Daniel M. Mulcahy·Ron Pascho
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Abstract

The incidence and titer distribution of infectious hematopoietic necrosis virus in cavity fluid from spent female sockeye salmon ( Oncorhynchus nerka ) varied little when fish from a naturally spawning population were sampled three times on alternate days. However, when prespawning female sockeye salmon from a second population were individually tagged, penned, and sampled daily, the incidence and proportion of fish with high virus titer rose over a 6-d period. In 10 instances, consecutive cavity fluid samples from the same fish reverted from virus-positive to virus-negative. We suggest that spent fish should be sampled when accurate and quantitative data on the incidence and level of the virus are required.

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Canadian Journal of Fisheries and Aquatic SciencesArticle

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Daniel M. Mulcahy, Ron Pascho. 1986. Sequential tests for infectious hematopoietic necrosis virus in individuals and populations of sockeye salmon. https://doi.org/10.1139/f86-310

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