Characteristics of a new birnavirus associated with a warmwater fish cell line

A warm-water fish cell line developed from blotched snakehead caudal pedunc le (BSN) was found to have persistent birnavirus infection, Purified virus particles were of icosahedral shape and had 57 +/- 1.6 nm diameter. The BSN virus was resistant to 5-iodo-2'-deoxyuridine and induced yellowish-green cytoplasmic inclusions when stained with acridine orange. The virus was res istant to chloroform, acid and alkaline pH and heat treatment at 56 degrees C for 2 h. Purified virions had a buoyant density of 1.33 g/ml in CsCl and contained two genomic segments with molecular masses of 2.56 x 10(6) and 2 .00 x 10(6) Da and four structural polypeptides of 112 (polyprotein, PP), 9 1 (VP1), 44 (VP2) and 37 (VP3) kDa, Reciprocal beta cross-neutralization te sts incorporating four classical strains of infectious pancreatic necrosis virus (IPNV) (WB, Sp, Ab and TV-1) and the BSN virus established the comple te serological distinctness of the virus from IPNV. Considering the uniquen ess of the virus, the name blotched snakehead virus is proposed for this ag ent.