Antituberculous drug susceptibility testing of Mycobacterium bovis BCG strain Montréal.

Testing of Mycobacterium bovis BCG strain Montréal for susceptibility to four primary antituberculous drugs (isoniazid, ethambutol, streptomycin, and rifampin) and to one secondary drug (p-aminosalicylic acid) showed the strain to be susceptible to all five substances. Mycobacterium bovis strains ATCC 35735, which is isoniazid sensitive, and ATCC 35747, which is isoniazid resistant, were included in the test; with the exception of their respective susceptibility to isoniazid, both were inhibited by the other four drugs.