Isolation and preliminary characterization of several viruses from koi (Cyprinus carpio) suffering gill necrosis and mortality

The present communication describes the isolation of seven viruses from dis eased koi carp during the last two years in our laboratory. All isolates ca used cytopathogenic effects in CCB and CaF-2 cell lines. Six isolates were sensitive to chloroform treatment, four isolates passed 100 nm filters and only one isolate were found to be sensitive against treatment with JUDR. Tw o isolates were identified as strains of spring viremia of carp virus (SVCV ). The results inclusive electron microscopical visualization allow a preli minary classification, but further investigations are necessary for exact t axonomic classification of the pathogens and for the determination of their pathogenicity.