Isolation and molecular identification Mycobacterium avium subsp. Paratuberculosis, from milk samples of Tehran province’s dairy Farms

A study was performed in the Persian capital province of Tehran to assess frequency of Para tuberculosis in its operating cattle farms. As many as 8,000 cows were screened by a homemade ELISA system. Milk specimens were collected from detected reactor to perform confirmatory PCR-16srRNA, PCR-IS900 and PCR IS1311 experiments plus bacterial culture on specific media in search for Mycobacterium avium subsp Para tuberculosis (MAP). While among the 25 ELISA positive(0.3%) animals eight cases produced positive results in PCRs(0.1%) only three appeared positive in MAP isolation(0.04%). In deduction, we assume when it comes to selection of control measures against Ptb, in an environment with presumably high prevalence of Ptb like Tehran, ELISA is a much more sensible detection system compared to the zero false-positive method of bacterial culture.