Comparison between microscopic agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA) for detection of leptospiral antibodies in cattle

Abstract

Leptospirosis is a worldwide zoonosis caused by Leptospira interrogans. It causes financial loss to the cattle industry with decreased milk production, abortion, stillbirth, infertility, and mortality. This study was conducted to evaluate two serological techniques, the microscopic agglutination test (MAT) and the enzyme-linked immunosorbent assay (ELISA), for detection of leptospiral antibodies in cattle. Three hundred and fifty five serum samples were collected from five commercial dairy farms in Tehran suburb from December 2004 to June 2005. The results of the MAT protocol showed that 55 serum samples (15.49%) had detectable antibodies against at least one serovar of L. interrogans at a dilution of ≥ 1:100. Icterohaemorrhagiae was the most (42.52%) and ballum the least (1.15%) prevalent serovars among 87 positive reactions against different serovars of L. interrogans. Leptospiral antibodies were also detected by the ELISA in 77 sera (21.69%) of 355 samples. The results of this study also showed that 2.25% of the sera that reacted positive in the MAT were negative by the ELISA, and 8.45% of the MAT negative sera were positive by the ELISA. Comparison between two techniques showed that there was a high correlation (0.61 < kappa = 0.649 < 0.8) between the ELISA and MAT for detection of leptospiral antibodies in cattle.