Desenvolvimento e avaliação de um ensaio imunoenzimático para o diagnóstico sorológico da infecção pelo herpesvírus bovino 1 Development and evaluation of an enzyme-linked immunosorbent assay for the serological diagnosis of the bovine herpesvirus 1 infection

An indirect enzyme-linked immunosorbent assay (ELISA) using non-purified antigen was developed for serological diagnosis of the bovine herpesvirus 1 (BoHV-1) infection. Some blocking substances to prevent nonspecific reactions were evaluated in different concentrations and combinations. The best results were obtained using 5% skim milk powder as blocking solution and the serum/conjugated buffer added with 10% MDBK cells, 10% equine serum, 1% skim milk powder. The system was evaluated with a collection of positives (n=60) and negatives (n=62) bovine serum previously analyzed by seroneutralization (SN) technique for the BoHV-1 antibodies. The indirect ELISA standardized showed 98.3% of sensitivity and 95.2% of specificity (kappa: 0.93) when compared with the SN technique. These results would allow its implantation in the laboratorial routine for the serological diagnosis of the BoHV1 infection. The use of non-purified antigen in ELISA facilitate the elaboration, reduces the production cost and makes possible the application of these technique in seroepidemiological study of the BoHV-1 infection in cattle herds.