The role played by market milk as a vehicle in transmitting Mycobacterium bo vis to man was denoted by the bacteriological investigation of 85 samples collected from dairy shops and street venders in Assiut City.
The means of identification and classifcation used were chiefly thiosemicarbazone sensitivity, sodium salicylate susceptibility, photochromogenicity test, catalase activity at the three different temperatures, Peknice and Asmus – Gorschagen's niacin test, indirect virtanen - Gries test, and nicotinamidase test.
The results obtained from this piece of work revealed that 13 out of 85 milk samples examined (15.3%) were culturaly positive. of these, one (1.2%) was found to be Mycobaterium bo vis, 6 (7.06%) scotochromogens, one (1.2%) non-photochromegens and 5 (5.9%) as rapid growers.