Sixty three samples of dairy creamery effluent were examined for the presence of mycobacteria. Thirty two strains were isolated from 27 samples. These were classified as follows: M. fortuitum (13), M. peregrinum (6), M. gordonae (5), M. marianum (scrofulaceum) (4), unidentified (4).
Ten strains, representative of the groups isolated, were tested for their effect on experimental animals. None were pathogenic for guinea pigs or mice but a number produced a minimal amount of skin sensitization in guinea pigs to avian and mammalian tuberculin.