An evaluation of three serological tests for antibody to Brucella suis in pigs

Abstract

The Rose Bengal Plate Agglutination test (RBT), the complement fixation text (CFT) and the tube agglutination test (TAT) were applied to serums from 345 feral and 80 domestic pigs sampled at slaughter. At least 2 of the 3 serological tests were applied to each serum. Tissues from all pigs were cultured for Brucella suis and the degree of culture effort was categorised from 1 to 4 in decreasing order. Fifty-eight feral and 35 domestic pigs were culture-positive. A greater proportion of culture-positive pigs was obtained for category 1 and 2 culture effort. Tissues yielding B. suis most often were mandibular, gastrohepatic and external iliac lymph nodes, spleen and various abdominal organs. Infection in domestic pigs was associated with exposure to feral pigs. The sensitivity (Se) in culture-positive pigs of the RBT (79.1%) was significantly greater than that of either the CFT (49.1%) or TAT (51.1%). The specificities (Sp) in culture-negative pigs were 81.2% for the RBT, 90.8% for the CFT and 81.0% for the TAT. A more realistic estimate of Sp for the RBT was considered to be 97.6%, based on serological results from 31,326 domestic pigs routinely tested for regulatory purposes. The RBT was clearly superior to the other 2 tests in this study. However, a more sensitive screening test would be preferable for use in a test and slaughter eradication program. The RBT would be a suitable confirmatory test.

Serological survey of the wild boar (Sus scrofa) for tularaemia and brucellosis in South Moravia, Czech Republic

“…Sensitivity and specificity of MAT with stained antigen have been demonstrated to be comparable or superior to those of the standard tube agglutination test with unstained antigen (Francis and Evans, 1926) in both Francisella (Massey and Mangiafico, 1974;Brown et al, 1980;Sato et al, 1990) and Brucella (Bettelheim et al, 1983;Moyer et al, 1987;Rogers et al, 1989;Sato et al, 1990). We can confirm that MAT compared with the standard tube agglutination 'macrotest' is quicker, easier to perform, more economical (saving sera and antigens) as well as better readable when the sera are haemolytic.…”

Evaluation of the Fluorescence Polarization Assay and Comparison to Other Serological Assays for Detection of Brucellosis in Cervids

“…The sensitivity in culture positive and the specificity in culture negative pigs was 49% and 91%, respectively (Rogers, 1989). However, it had not been previously evaluated for detection of antibody to Brucella suis in Cervidae.…”

Detection of brucellosis and leptospirosis in feral pigs in New South Wales

“…Note that the CFT for Brucella antibody is generally considered to be more highly specific for infection with this organism (sensitivity: 49.1%, specificity: 90.8%). 22 Using the two tests is cost-effective and improves overall accuracy by combining the higher sensitivity of one test (RBT) with the higher specificity of the other (CFT).…”