Survival of Mycobacterium bovis in defined environmental conditions.

The survival of Mycobacterium bovis was investigated following artificial inoculation in dry and moist soils and bovine faeces held under various environmental conditions. M. bovis survived for 4 weeks in non-sterile dry and moist soils held under 80% shade, in darkness and in the laboratory. It was also isolated from sterile moist soil kept in the shade and in darkness. Re-isolation of M. bovis was not made at 4 weeks from any of the substrates exposed to sunlight nor from faeces held under any condition. M. bovis was not re-isolated from any substrate at 8 weeks or up to 32 weeks after inoculation.