Detection of Mycobacterium paratuberculosis in raw cow’s milk using polymerase chain reaction (PCR) technique

Abstract

Paratuberculosis or Johne’s disease is a chronic debilitating disease mainly infects ruminants and caused by Mycobacterium paratuberculosis. Previous serological studies in Mosul city confirm the presence of positive reactants for paratuberculosis in cattle. However, culture methods to confirm the disease need a long incubation period and also special media. Raw cow’s milk is considered as potential source for transmission of M. paratuberculosis in cows’ herds. Accordingly, this study aimed to detect the presence of M. paratuberculosis specifically in the raw cow’s milk using polymerase chain reaction (PCR) technique as a rapid, sensitive and reliable method. A total of 50 samples of raw cow’s milk were collected from cows suffering from emaciation and unresponsive to antibiotic treatment. All the samples were subjected to DNA extraction and direct amplification PCR. The results showed that 3 (6%) out of 50 milk samples were positive for M. paratuberculosis. This is the first study in Mosul city that confirms the presence of M. paratuberculosis in raw cow’s milk using PCR technique. In conclusion, raw cow’s milk could be an important source for M. paratuberculosis infection in dairy cows, and also PCR technique could be helpful in rapid diagnosis of paratuberculosis.

Keywords

• mycobacterium paratuberculosis
• pcr
• cow’s milk
• johne's disease