Location: Poultry Microbiological Safety Research
Title: Utilizing a gentamicin resistant Campylobacter (C. coli) in poultry research Authors
Submitted to: International Poultry Forum Proceedings
Publication Type: Proceedings
Publication Acceptance Date: October 15, 2007
Publication Date: July 20, 2008
Citation: Cox Jr, N.A., Richardson, L.J., Buhr, R.J., Cray, P.J., Berrang, M.E., Bailey, J.S., Northcutt, J.K. 2008. Utilizing a gentamicin resistant Campylobacter (C. coli) in poultry research. International Poultry Forum Proceedings. Poul Sci: 87 (S1): 168. Technical Abstract: The capability to perform inoculation studies with Campylobacter is limited without a suitable marker. Performing inoculation studies without a marker requires utilization of molecular techniques for confirmation. The objective of this study was to screen over 3,000 Campylobacter isolates obtained from poultry carcass rinses for a unique antibiotic resistant pattern. A C. coli strain was found to be naturally resistant to gentamicin above 32ug/mL. Gentamicin was incorporated into several media (Campy cefex, Brucella, and Blood agar) at varying levels from 50 ppm up to 1000 ppm. The isolate was then streaked onto each plate to determine the level of gentamicin resistance of the isolate. Ceca and post-pick carcass rinses were obtained and streaked onto the gentamicin plates to determine whether extraneous microflora is excluded. Next, the C. coli strain was orally and intracloacally inoculated into several chicks. At three weeks of age, the inoculated birds from each pen were removed and the spleen, thymus, liver/gallbladder, unabsorbed yolk and ceca were sampled for the presence of the C. coli. At six weeks of age, 3 birds were removed and the above procedure performed along with ceca samples from 10 additional pen mates. In addition, the C. coli was inoculated onto commercial pre-chill broiler carcasses and the carcasses rinsed to determine whether the inoculated marker could be recovered. The C. coli was found to be resistant up to 400 ppm gentamicin. Campy cefex media with gentamicin was the only media where breakthrough of extraneous organisms from ceca did not occur at 100 ppm of gentamicin. C. coli was found to colonize chicks by either route of inoculation, disseminate to tissues, colonize pen mates and persist for the 6 week grow-out. The marker organism was also recovered from chicken carcass rinse and excluded background microflora. This C. coli strain functioned similarly to other Campylobacter cultures. Its unique characteristics of being resistant to rather high levels of gentamicin makes it a very valuable tool for a wide range of Campylobacter research projects involving live birds and processing plant studies.