Mouse intestine colonization ability of Campylobacter coli strains

Campylobacter coli is an etiological agent of gastrointestinal and extraintestinal infections in man and animals, and can be found as a commensal in gastrointestinal tract of animals. In this study, we aimed to determine differences among C coli strains in colonization of the intestinal tract of mice. Seven C coli strains isolated from diarrheic patients, asymptomatic hosts and chicken carcasses were used for this study. Each strain was inoculated with 0.1 ml of a bacterial suspension (3 x 10(8) CFU/ml) to 5 weanling mice, intragastrically. For the isolation of C coli, faecal pellets collected before inoculation and after inoculation at particular intervals were cultured on Campylobacter Selective Agar. Seven C. coli strains were divided into 3 colonization groups, based on faecal shedding. Group I showed immediate colonization, with prolonged excretion of organism in all mice. Group II showed delayed and short time colonization of C. coli. Group III could not colonize mice. Division of isolates into colonization groups was as follows: Group I included 3 strains from gastrointestinal disease; Group II included 2 strains from asymptomatic hosts and Group III included 2 strains from chicken carcasses. The study showed that there were marked differences among C coli strains with respect to their colonization potential and it may depend upon the origin of the strain. For understanding the complete pathogenesis of Campylobacter spp., a greater number of strains from different sources and geographical locations require to be tested in further investigations in the light of our findings.