detection of mycobacterium avium subsp. paratuberculosis in cows from urmia region

john`s disease, is an important disease in cattle which the causative agent is mycobacterium avium subsp. paratuberculosis. economic losses, elimination of reactor cattle, high expenses of disease control and causing crohn disease in human made the study of disease more important. knowing the involved area, focal points of disease would be effective to prevent disease. there are several methods available to detect mycobacterium avium subsp. paratuberculosis including: culture of fecal samples, culture tissue samples from abattoir or serological testing. this study was conducted to detect mycobacterium avium subsp. paratuberculosis and regional distribution of johne`s disease in urmia. in this study, a total number of 400 cows between 6 months to 5 year of age were tested using culture of fecal samples. samples were cultured on middle brook medium and colonies were appeared after 8 weeks. according to morphological appearance of colonies, acid- fast staining, comparison of colony with reference strain and specificity of medium it was distinguished that the isolated bacterium is mycobacterium avium subsp. paratuberculosis,. out of 400 samples, culture results in 12% (n = 48) were positive and others were negative.