USE OF THE POLYMERASE CHAIN-REACTION FOR THE DETECTION OF RETICULOENDOTHELIOSIS VIRUS IN MAREKS-DISEASE VACCINES AND CHICKEN TISSUES

Reticuloendotheliosis virus (REV) proviral DNA appears to be a frequen t contaminant in Marek's disease (MD) vaccines. A polymerase chain rea ction (PCR) was established and evaluated for its ability to detect RE N proviral DNA in infected cell cultures and chicken tissues. Deoxynuc leotide primers were selected from the highly conserved gag region of the REV genome. The amplification products were identified by electrop horesis, nested PCR and by hybridization with a digoxigenine-labelled oligonucleotide. The PCR results correlated well with the diagnosis ob tained by conventional procedures, i.e. virus isolation or indirect im munofluorescence test (IIFT).