The work is devoted to the investigation of antigenic specificity of M. avium surface components. Usage of crossing immunoelectrophoresis allowed to show that two groups of antigens are present: “cathode” and “anode”. Specific antigens were absent among “cathode” components whereas among “anode” components there was an antigen which didn’t react with any of used sera. It gives a possibility to suggest that it is species-specific for M. avium.
