DAO 41:219-223 (2000)  -  doi:10.3354/dao041219

ABSTRACT: Barfin flounder nervous necrosis virus (BFNNV), the causative agent of viral nervous necrosis (VNN) of barfin flounder, is vertically transmitted from spawners to larvae. In the present study, an ELISA with a recombinant protein of BFNNV was performed for the detection of antibodies against BFNNV and applied for the selection of brood fish in order to prevent viral vertical transmissions. Brood stocks were divided into 4 groups based on ELISA antibody titers (≤10, 20, 40 and >40), and t BFNNV status of the brood stocks was determined by PCR. BFNNV was detected from the brood fish in the group with an antibody titer of >40 but not from those with titers ≤10, 20 and 40. The offspring obtained from PCR-negative brood fish pairs in ea group of ELISA antibody titers were subsequently reared for observation of VNN occurrence. VNN occurred in juveniles from 2 of 9 pairs of spawners with an antibody titer ≥40, but did not occur in spawners with an antibody titer of ≤10. Therefore, it concluded that selection of brood fish using both the PCR test and ELISA antibody titers could help prevent vertical transmission of BFNNV in larval production of barfin flounder.

KEY WORDS: Viral nervous necrosis (VNN) · Barfin flounder nervous necrosis virus (BFNNV) · Selection of brood fish · Recombinant protein · ELISA antibody titer