The interplay between Campylobacter and Helicobacter species and other gastrointestinal microbiota of commercial broiler chickens.

BACKGROUND: Poultry represent an important source of foodborne enteropathogens, in particular thermophilic Campylobacter species. Many of these organisms colonize the intestinal tract of broiler chickens as harmless commensals, and therefore, often remain undetected prior to slaughter. The exact reasons for the lack of clinical disease are unknown, but analysis of the gastrointestinal microbiota of broiler chickens may improve our understanding of the microbial interactions with the host. METHODS: In this study, the fecal microbiota of 31 market-age (56-day old) broiler chickens, from two different farms, was analyzed using high throughput sequencing. The samples were then screened for two emerging human pathogens, Campylobacter concisus and Helicobacter pullorum, using species-specific PCR. RESULTS: The gastrointestinal microbiota of chickens was classified into four potential enterotypes, similar to that of humans, where three enterotypes have been identified. The results indicated that variations between farms may have contributed to differences in the microbiota, though each of the four enterotypes were found in both farms suggesting that these groupings did not occur by chance. In addition to the identification of Campylobacter jejuni subspecies doylei and the emerging species, C. concisus, C. upsaliensis and H. pullorum, several differences in the prevalence of human pathogens within these enterotypes were observed. Further analysis revealed microbial taxa with the potential to increase the likelihood of colonization by a number of these pathogens, including C. jejuni. CONCLUSION: Depletion of these taxa and the addition of taxa that compete with these pathogens, may form the basis of competitive exclusion strategies to eliminate them from the gastrointestinal tract of chickens.

A novel miniaturized most probable number method for the enumeration of Campylobacter spp. from poultry-associated matrices.

A novel miniaturized most probable number (mMPN) method was developed for the enumeration of thermophilic Campylobacter spp. using a modification of blood-free Bolton broth (supplemented with 25mg/l of sulfamethoxazole) and CampyFood ID agar. The mMPN was evaluated by comparison with direct plating (modified ISO/TS, 10272-2:2006) for the analysis of samples (n=149) representing various poultry matrices (carcases, broiler ceca and feces, scald tank water and feed). A sensitivity of 95%, specificity of 90% and Cohen KAPPA agreement of 0.84 was determined for the mMPN method compared to direct plating. Quantitative comparison found 83% of enumerations to be less than ±1log10 different (Student's t-test P<0.001). Financial analysis showed that the mMPN required 51% less media and 60% less labor than the direct plating protocol. The mMPN provides a method that can be used for complete through-chain analysis that has a single enrichment step and multiple dilutions to extinction for a variety of samples (containing low, medium and high populations).