Development of a blocking latex agglutination test for the detection of antibodies to chicken anemia virus

•A blocking latex agglutination test was developed.•The test showed high specificity for detecting antibodies to chicken anemia virus.•High test sensitivity is comparable with a neutralization test.•The test is rapid, with results obtained within 5 min.•The test is a useful and reliable tool in serology studies of chicken anemia virus.

A blocking latex agglutination test (b-LAT) developed in this study was evaluated for the detection of antibodies against chicken anemia virus (CAV) in chickens. Polystyrene latex beads were coupled with a neutralizing monoclonal antibody (mAb) to CAV (mAb-beads). When mAb-beads were mixed with antigens prepared from the lysate of MDCC-MSB1 cells infected with CAV, agglutination occurred. A short pre-incubation of CAV antigens with CAV-specific antiserum inhibited the agglutination of mAb-beads. The test results were obtained within 5 min. The specificity of b-LAT was evaluated using sera from specific pathogen-free chickens and sera containing antibodies to avian influenza virus, Newcastle disease virus, infectious bursal disease virus, and Marek's disease virus; nonspecific agglutination and cross-reactivity with antibodies to unrelated viruses were not observed. The examination of 94 serum samples collected from commercial breeder chickens of various ages (17-63 weeks) revealed good agreement (93.6%, Kappa value = 0.82) between b-LAT and a virus neutralization test, known to be most sensitive and specific in the detection of antibodies to CAV. These results indicate that b-LAT, a simple and rapid test, is a useful and reliable tool in CAV serology.