Study on the interference of vaccine antibodies in the serological diagnosis of leptospirosis in cattle

Abstract

A simple whole-cell-based IgG ELISA specific for Leptospira spp. was compared with the microscopic agglutination test (MAT) to detect IgG antibody responses to a com mercial vaccine in cattle. After initial vaccination (10 cows), specific antibodies to Leptospira spp. were detected in 90% of animals by IgG-ELISA and 60% by MAT, whereas after booster, antibodies were detected in 100% and 90% of animals by IgG-ELISA and MAT, respectively. Interferences by vaccine antibodies were evident with both MAT and ELISA serological tests. For the diagnosis of the disease, it would be advisable to use the ELISA method from two and a half months post-vaccination and the MAT method from four months post-vaccination to avoid interference by vaccine antibodies. On the other hand, our results suggest that IgG-ELISA has the potential to be a useful method to evaluate the development of IgG antibodies in duced by leptospira vaccine.