Preliminary study of molecular identification of Mycobacterium bovis from cow's milk in Lorestan (Iran)

Bovine tuberculosis is one of the most important common infectious diseases between humans and livestock. Cow's milk can be investigated as one of the transmission reservoirs of the disease. Our study was conducted to investigate the presence of Mycobacterium bovis (M. bovis) DNA in cow's milk from different regions of Lorestan province using Touch-down PCR (TD-PCR) method. So, 100 milk samples from industrial and traditional cattle farms were collected and evaluated according to the animal breed, the average age of the animal and the region where the animal was kept. Seven (26.9%) out of the 26 cow's milk samples contaminated with Mycobacterium spp., were diagnosed as M. bovis positive. The cattle with an average age of more than 5 years were most infected with Mycobacterium. Also, the crossbred cattle with an average age of 3 to 5 years, which were kept and raised in tropical areas, showed the highest rate of M. bovis infection. Based on our knowledge, this is the first study regarding the presence of Mycobacterium in cow's milk in Iran.