Brucella canis Isolates from Canadian Dogs.

Eleven Brucella canis isolates from Canadian dogs were characterized by dye and antibiotic sensitivity, phage susceptibility, urease and H(2)S production, CO(2) requirement, and reaction with monospecific A,M, and R anti-Brucella antiserum. The isolates could be separated into two distinct groups. One group had a sensitivity pattern similar to that seen with the American type strain RM666, while the other group had a pattern identical to that of a Mexican strain, Mex 51. Epidemiological studies supported contraction of infections in the United States and Mexico respectively. The characteristics of all isolates were stable after repeated subculture indicating that strain differences could serve as useful epidemiological markers and supporting division of the species into two biovars.