Comparison of Bacteroides zoogleoformans strains isolated from soft tissue infections in cats with strains from periodontal disease in humans.

A total of 11 strains of Bacteroides zoogleoformans were isolated from 11 of 106 different cat subcutaneous "fight wound" abscesses and were among a total of 143 Bacteroides species isolated from these samples. They constituted 3.4% (11 of 325) of all anaerobic isolates. The cat strains and strains of B. zoogleoformans isolated from humans with periodontal disease were similar phenotypically as determined by biochemical reactions, polyacrylamide gel electrophoresis patterns of soluble proteins, and guanine plus cytosine ratios of DNA. Eight cat strains and five human strains tested had 45 to 54% DNA homology with the type strain of B. zoogleoformans. The eight cat strains and five human strains (excluding the type strain) were related by DNA homology at 70 to 77%. There was 85 to 90% intragroup DNA homology among the cat strains and 86 to 89% intragroup homology among the five human strains. The implications for epidemiology and human and animal ecology are discussed.