A conglutination test for rapid detection of antibodies against Babesia bigemina

Abstract

A rapid conglutination test (RCT) with performance comparable to the indirect fluorescent antibody technique (IFAT) was developed to detect antibodies against Babesia bigemina (B. bigemina-RCT). The B. bigemina-RCT is a sensitive, specific, economical, and rapidly performed serological test suitable for field application or minimally equipped laboratories. This test had a sensitivity of 90.9%, and specificity of 97.6%, compared to IFAT, which showed for the same parameters respectively, 98.3% and 99.7%. The early detection of anti- B. bigemina immunoglobulins by RCT in experimental infections was nearly parallel to that of IFAT. Cross reactions were observed with sera from calves experimentally infected with Babesia bovis (1.8%) and with Anaplasma marginale (1.2%). RCT antigen prepared with non parasitized erythrocytes (negative antigen) showed 1.5%, 3.5% and 2.2% of positive reactions with sera from animals experimentally infected with B. bigemina, B. bovis and A. marginale. However, none of the sera from animals of endemic areas for babesia infection resulted in positive reactions with the negative antigen. Considering these results and shelf life over six months, the B. bigemina-RCT could be used for epidemiological surveys and evaluation of control measures against this species of Babesia.

Diagnostic Tools for the Identification of Babesia sp. in Persistently Infected Cattle

“…The CFT reaction is dependent on the presence of complement fixing antibodies, wherein most of the important isotype is the IgM immunoglobulin. Thus, early infections are detected, but it is not suitable for detecting chronically infected animals [76]. CFT was compared to the IFAT in different studies in cattle samples collected in the field.…”

“…This test showed high sensitivity and specificity rates, 90.9% and 97.6%, respectively. Thus, the RCT assay was considered as a sensitive, economical and easy assay, appropriate for conducting epidemiological surveys [76]. However, the RCT was not reported any more as a diagnostic tool for B. bovis .…”