Diagnosis of brucellosis in dairy animals using nested polymerase chain reaction

Abstract

In this study, a total number of 92 milk samples collected from obligatory slaughtered 32 cattle, 30 buffaloes and 30 sheep suspected for brucellosis in different governorates of Egypt were tested using the nested Polymerase Chain Reaction (nPCR). Thirty eight out of the 92 milk samples (41.3%) gave the expected product. The sensitivity of nested PCR using vaccinal strains S19 and Riv I vaccine, ranged between as high as 10-102 cfu mL-1. The nesting of PCR resulted in rise of PCR sensitivity, by about 10 folds. Bacteriological studies yielded 16 (17.3%) Brucella isolates recovered from milk (6 from cattle, 4 from buffaloes and 6 from sheep), they were typed as Brucella melitensis biovar 3. It could be concluded that using nested PCR as confirmatory test for detection of susceptible dairy animals, is of great value to avoid condemnation of false positive reactors, which reflects economically on animal resources. © 2008 Academic Journals Inc.