Genomic (5'UTR) and serological differences among German BVDV field isolates.

Isolates of bovine viral diarrhoea virus (BVDV) collected in Germany were examined for their genomic heterogeneity in sequences from the 5'untranslated region (UTR) of the viral genome. Polymerase chain reaction (PCR) tests based on the 5'UTR and the region coding for the NS2-3/4A polypeptide were used to differentiate between BVDV I and BVDV II genotypes. Eleven out of 96 BVDV-isolates were identified as BVDV II. Virus neutralization tests with BVDV I- or II-specific antisera raised in cattle were done. The mean titers were reduced by 7.2-fold (BVDV I-antiserum versus type II-isolates) or 35-fold (BVDV II-antiserum versus type I-isolates) when using the respective heterologous virus.