Mycobacterium avium subsp. paratuberculosis (MAP), the etiological factor in Johne's disease of cattle, is also mentioned as one of the factors that could cause the Crohn's disease - a chronic, ulcerating distal ileitis in people. Despite a significant progress of studies on isolation of MAP, culturing of microorganisms on microbiological media is so far the only method allowing confirmation of presence of live bacterial cells in the examined samples. MAP is difficult to culture in vitro. The time required for obtaining colonies is long as at least 4 weeks are required (most frequently 12-14 weeks). Culturing on media supplemented with mycobactin J is an important factor allowing differentiation of MAP from other microorganisms of Mycobacterium avium complex. Herrold's medium (HEYM), Middlebrook 7H9 medium and Löwenstein-Jensen medium, all supplemented with mycobactin J are the media recommended by O.I.E for isolation and culturing of MAP. This study aimed at a comparison of speed and intensity of MAP growth on the listed media without and with a supplement of antibiotics (vancomycin and naladixic acid at 20 mg per 1 liter of medium). The cultures were incubated at 37°C. To confirm a dependence of MAP growth on the presence of an iron chelating agent, each sample was inoculated on 2 HEYM slants, 2 Middlebrook 7H9 slants and 2 Löwenstein-Jensen slants without the supplement of mycobactin J. Growth observation started from the fourth week of incubation. The moment of appearance of the first colonies, their looks and rate of growth were recorded. The fastest MAP growth (after 5 weeks of incubation) was obtained on HEYM medium, a slightly slower growth on Löwenstein-Jensen medium (6-9 weeks). Incubation for 16 weeks did not allow obtaining MAP growth on Middlebrook 7H9 medium supplemented with antibiotics.