Antagonistic activities of several bacteria on in vitro growth of 10 strains of Campylobacter jejuni/coli.

Chicken meat contaminated with Campylobacter jejuni can be the source of human enteritis. To decrease the risk of human infection, Campylobacter should be controlled at farm levels. Orally given probiotic bacteria could prevent colonisation of chicken with pathogenic bacteria like Campylobacter. The aim of this study was to investigate the effect of different bacteria on Campylobacter growth. Our results demonstrated that bacteria isolated from conventional chicken had potential inhibitory activities against Campylobacter. Other bacteria not isolated from chickens but with known antagonistic capacities, e.g. Enterococcus (56 strains) and Escherichia coli (20 strains), did not show any negative effect on Campylobacter. Interestingly, one Lactobacillus (P93) strain isolated from the chicken gut showed bactericidal activity against all tested Campylobacter. The bactericidal effect was characterised as the production of organic acids in combination with probably production of an anti-Campylobacter protein. In a co-culture study of Campylobacter and Lactobacillus (P93), the culturability of Campylobacter was under the detection limit after 48 h of incubation. A chicken experiment is needed to further evaluate the effect of the promising probiotic bacteria against Campylobacter colonisation in chicken.