Dzyombak D. Biological properties and survival rate of pathogenic and atypical mycobacteria in the milk products and environment.

Materials concerning the viability of mycobacteria in ensilage and in urine, terms of which are from 120 to 210 days, are presented in the dissertation. There has been studied survival rate and variability of mycobacteria at their stay in the milk, yogurt and sour cream: M. bovis - 160, 160 and 250 days, M. avium - 550, 550 and 350 days, M. intracellulare - 500, 220 and 250 days, M. scrofulaceum - 550, 550 and 550 days, M. fortuitum - 250, 180 and 180 days. In M. bovis and M. fortuitum there was observed dissociation of colonies on the R- and S forms, which retain specific for this type of mycobacteria properties. All cultures, which grew at 22 and/or 45 °С and had catalase activity, lost these properties in the end of experiment with the exception of M. intracellulare. Terms of viability in sterilized and native samples of black soil, loam and sand in laboratory conditions and in soil under the natural conditions have been studied. M. bovis survives in these objects from 3.5 to 20 months, M. avium - from 15 to 21 months, M. fortuitum - from 11 to 22 months. Data concerning terms of mycobacteria survival in the samples of tap water, distilled and well water under the different storage conditions has been obtained. Under the influence of penetrating sunlight, M. bovis does not lose viability for 51-61 days, without access to sunlight - for 98-113 days, M. avium - for 113-128 and 113-128 days respectively, M. intracellulare - for 98-113 and 128-216 days, M. scrofulaceum - for 147-216 and 243-302 days, M. fortuitum - for 28-33 and 72 days. In the refrigerator (2-6 °С), these terms vary from 152 to 800 days (period of observation). Along with this, the method of L form mycobacteria isolation from environmental objects and from livestock products has been developed, and method of mycobacteria isolation from the environmental objects has been improved.