Comparison of four serological tests for the diagnosis of swine brucellosis

Abstract

The purpose of this article is to present results of a research in which the results of four serological tests were compared for the diagnosis of swine brucellosis in pigs from Brazilian herds in which the outbreak occurred in relation to other brucellosis-free. Rose Bengal (RBT), complement fixation (CFT), agglutination plus 2-mercaptoethanol test (TAT+ME), and commercial fluorescence polarization assay (FPA) were used to test 333 sera (271 sows and 62 finishing pigs) from a Brucella suis infected swine herd and 1,100 swine sera from brucellosis free pigs taken at a slaughterhouse. Considering infected all the 271 sows from the outbreak, and interpreting results of the FPA according to the manufacturer directions, sensitivities observed were 95.94% for FPA, 94.83% for RBT, 93.73% for CFT, and 92.25% for TAT+ME. Considering infected all the pigs from the infected herd with a positive result in at least one test, sensitivities observed were 98.92% for RBT, 97.13% for CFT, 96.06% for FPA, and 94.98% for TAT+ME. Specificities of the tests were CFT and TAT+ME, 100%; FPA, 99.55%; and RBT 99.27%. Results indicated a good performance of all the tests, and the agreement among them was almost perfect.

Evaluation of the Fluorescence Polarization Assay for the Diagnosis of Brucellosis in Goat Milk

“…Comparison between ROC curves obtained in the FPA test and the RBT in field milk and serum samples (Figure 5) showed no significant differences (Table 1), which may indicate no differences in the use of the FPA test in milk samples and the RBT in serum. Similar results have been observed in pig serum samples, where Se and Sp values between RBT and FPA (Se: 94.83, Sp: 99.27 and Se: 96.06, Sp: 99.54, respectively) were comparable [46]. FPA in goat milk showed lower Se and Sp than FPA and RBT3 in serum or bovine milk (Table 2).…”