Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/11/2000
Publication Date: N/A
Interpretive Summary: Campylobacter jejuni is a human enteropathogen that has been associated with the consumption of poultry. Campylobacter are not tolerant of dry conditions and many poultry-associated samples have relatively low water activity levels. Therefore due to the fragile nature of the microorganism and the dryness of the samples, Campylobacter either die or become unculturable, which results in an underestimation of the presence of this bacterium in many poultry samples. In order to obtain useful epidemiological data on Campylobacter in poultry, non-cultural laboratory techniques will have to be used to verify the presence of this organism in many dry poultry samples.
Technical Abstract: Five cm(2) of clean unused chick pads, 5 g of unused pine shaving litter and fresh unsanitized broiler breeder eggshell halves were inoculated with C. jejuni. Inoculation levels were 10(2), or 10(3) cells per sample. The samples were allowed to remain at room temperature for 15, 30 or 60 min before addition of enrichment broth. All samples were enriched in Bolton's broth and plated on Campy-cefex agar. Characteristic Campylobacter confirmed as members of the species jejuni, lari or coli with a latex agglutination test. When chick pad samples were inoculated with 10(2) cells, Campylobacter were consistently recovered 15 minutes later. However, by 30 min less than half of the samples had detectable levels of Campylobacter, and by 60 min Campylobacter could be detected in only 4 out of 22. With litter samples, only one of those inoculated with 10(2) cells were positive after 15 min and no positives were found after 30 min or 60 min. When 10(3) cells were inoculated onto litter, Campylobacter was recovered from 11 of 20 samples at 15 min and only one of 20 samples after 30 min. Eggshells were also found to be a harsh environment. When the inoculum was 10(2) at 15 min 8 of 12 samples were positive but at 60 min only one of 12. The current cultural methods may not be adequate for recovering low numbers of Campylobacter from dry samples. Perhaps Campylobacter are present and culturally undetectable in the commercial hatchery and hatchery environment.