Molecular study of Brucellosis in camels by the use of TaqMan® real-time PCR

Abstract

Brucellosis is a zoonosis of economic importance that reduces productivity in livestock enterprises as it induces abortion in infected animals. A study was designed aimed at detecting Brucella in blood and lymph node specimens from camels by the use of real-time PCR in Iran. Sample collection and DNA extraction were done on blood (n = 135) and lymph node (n = 135) samples collected from 135 camels (abattoir survey) from both sexes at various ages in different seasons. The real-time PCR for species differentiation was based on unique genetic loci of B. melitensis and B. abortus. The regions were chosen for the construction of primers and TaqMan® probes for species differentiation: BMEII0466 gene for B. melitensis and Bru-Ab2_0168 gene for B. abortus. Brucella spp. were identified in 18 (13.33%) blood samples and 4 (2.97%) lymph node samples. This method showed to be effective in detecting B. abortus and B. melitensis in blood and lymph samples respectively. Brucella abortus was detected in 3 (2.22%) blood samples but was however, not detected in the lymph node samples. Brucella melitensis was only observed in 4 (2.97%) lymph node samples. Significant differences were observed on the blood prevalence of unknown Brucella spp. in different age groups and seasons (P < 0.05). However, there were no significant differences observed on the prevalence of B. abortus, B. melitensis, unknown Brucella spp. in different age groups, sex and seasons (P > 0.05). Therefore, Brucella was detected in apparent healthy camels slaughtered at an abattoir in Iran and this recommends the significance of the detection of Brucella in camels, since the infected camels appear to be healthy.