The present study reports the results of virological survey in fish with an emphasis on the diseases included in the Czech National Legislation. Monitoring of fish both without symptoms and with a manifested disease was performed within this virological surveillance. Between January 1999 and December 2006, viral haemorrhagic septicaemia virus (VHSV), infectious haematopoetic necrosis virus (IHN...

To study the molecular basis of virulence of viral haemorrhagic septicaemia virus (VHSV), we used a cross-reactive neutralizing MAb to select MAb-resistant (MAR) mutants with reduced pathogenicity for fish. From sequence determination of the G gene of MAR mutants, attenuated laboratory variant and avirulent field strains, we identified two distant regions of the glycoprotein associated with vir...

A commercial plant extract derived from olive tree leaf (Olea europaea) (LExt) and its major compound, oleuropein (Ole), inhibited the in vitro infectivity of the viral haemorrhagic septicaemia virus (VHSV), a salmonid rhabdovirus. Incubation of virus with LExt or Ole before infection reduced the viral infectivity to 10 and 30%, respectively. Furthermore, LExt drastically decreased VHSV titers ...

Seventy-four cultures of Pasteurella multocida representing all four capsular types, A, B, D, and C, from various animal species and diseases were examined for the production of hyaluronidase by two procedures. In one, hyaluronidase production was determined by the depolymerization of streptococcal capsular hyaluronic acid, and in the other, production was determined by degradation of sodium hy...