INTRODUCTION
Bovine tuberculosis is a chronic progressive disease caused byMycobacterium tuberculosis var. bovis which affects mainly cattle and buffalo but also infects other mammalian species of mammals, including humans (Cousins et al., 2003). The zoonotic potential of this disease is related to the consumption of raw milk and unpasteurized derivatives, representing the main route of transmission to humans, more pronounced in rural areas. In the state of Pernambuco, a prevalence of outbreaks of 2.87% and 0.62% of infected animals was reported in 2016, with a tendency to concentrate in the Agreste region of the state and with a predominance in dairy properties (Lima et al., 2016).
The interest in nucleic-acid based diagnostic procedures increased because of the limitations of conventional testing such as lack of sensitivity and specificity of the allergic-skin test and the long period for confirming the presence of the agent by bacteriological methods (Drewe and Smith, 2014). In addition, Molecular typing methods have provided a great impetus in the molecular epidemiology studies of the M. tuberculosis complex include comparing mycobacterial genome sequences. Among the most used genotyping techniques for the study of the M. tuberculosis complex are Spoligotyping and Variable Number of Interspersed Repetitive Units of Mycobacteria -MIRU-VNTR (Kamerbeek et al., 1997; Supply et al., 2006). The MIRU-VNTR has higher discriminatory power and has currently been the method of choice in the genotyping studies of Mycobacterium spp, and in particular related to M. tuberculosis var. bovis, allows identification of prevalent strains circulating in a herd or geographic regions (Kamerbeek et al., 1997; Supply et al., 2006).
M. tuberculosis var. bovis infection has an impact on both animal and human health, nonetheless, scarce are the studies in the region on molecular genotyping. Given the lack of data on the contribution and nature of Mycobacterium tuberculosis complex (MTBC) to bovine TB in the state of Pernambuco, we performed the genotypic characterization of Mycobacteria isolated from bovines from dairy herds in this region that were diagnosed clinically with tuberculosis, coming from dairy herds in the state of Pernambuco.