Rapid identification of Mycobacterium bovis by a thin-layer chromatographic technique.

Lipid analyses were performed on 107 isolates of mycobacteria, using thin-layer chromatography. A distinctive blue-gray spot was observed after spraying and charring at an Rf of 0.75 for 35 of 38 Mycobacterium bovis isolates examined. The spot, designated M bovis identifying lipid, was observed only with M bovis and was not seen on any other of 9 mycobacterial species examined. This procedure has a high rate of agreement (97.2%) with standard biochemical tests and can rapidly detect M bovis from naturally occurring infections. Although chemical and antigenic characteristics are not fully elucidated, the apparent specificity of this spot for M bovis represents a simple timesaving method for differentiating this species from other mycobacteria when compared with conventional methods presently used.