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Isolation, characterization and molecular identification of a novel aquareovirus that infects the endangered fountain darter, Etheostoma fonticola

Luke R. Iwanowicz·Deborah D. Iwanowicz·Cynthia R. Adams·Teresa Lewis·Tom Brandt·Lakyn R. Sanders·Robert S. Cornman
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Abstract

The fountain darter Etheostoma fonticola (FOD) is a federally endangered fish listed under the US Endangered Species Act. Here, we identified and characterized a novel aquareovirus isolated from wild fountain darters inhabiting the San Marcos River. This virus was propagated in Chinook salmon embryo (CHSE)-214, rainbow trout gonad-2 and fathead minnow cells at 15°C. The epithelioma papulosum cyprini cell line was refractory at all temperatures evaluated. High throughput sequencing technologies facilitated the complete genome sequencing of this virus utilizing ribosomal RNA-depleted RNA extracted from infected CHSE-214 cells. Conventional PCR primer sets were developed for the detection and confirmation of this virus to assist diagnostic screening methods. Phylogenetic analysis suggests this virus belongs to the Aquareovirus A genus. This research provides requisite initial data critical to support hatchery and refugia biosecurity measures for this endangered species.

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Luke R. Iwanowicz, Deborah D. Iwanowicz, Cynthia R. Adams, Teresa Lewis, Tom Brandt, Lakyn R. Sanders, Robert S. Cornman. 2019. Isolation, characterization and molecular identification of a novel aquareovirus that infects the endangered fountain darter, Etheostoma fonticola. https://doi.org/10.3354/dao03261

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