DAO 73:201-205 (2007)  -  doi:10.3354/dao073201

ABSTRACT: We used (1) ultracentrifugation followed by RT-PCR and (2) real-time RT-PCR to detect and quantify nodaviruses in seawater in which Atlantic halibut Hippoglossus hippoglossus larvae/fry had been held at rearing facilities. Evaluated against in vitro propagated viruses, the viral concentration corresponded to 1.6 × 10⁴ TCID₅₀ (50% tissue culture infectious dose) ml^–1. Evaluated against in vitro transcribed RNA, the concentration was estimated at 2 × 10⁷ virus particles ml^–1 seawater.

KEY WORDS: Nodavirus · RT-PCR · Real-time PCR · Quantification · Seawater · Atlantic halibut