|Cox, Nelson - Nac|
|RICHARDSON, L. - Coca-Cola Company|
|HARRISON, M. - University Of Georgia|
Submitted to: Journal of Food Safety
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/14/2014
Publication Date: 2/1/2015
Citation: Cox Jr, N.A., Richardson, L.J., Harrison, M.A. 2015. Efficiency of several cultural methods and a chick bioassay to recover dry stressed Campylobacter. Journal of Food Safety. 35:91-101.
Interpretive Summary: Campylobacter is the leading cause of bacterial gastroenteritis in humans. Raw poultry products have been implemented as a source of this infection and to reduce Campylobacter prevalence at the processing plant, further intervention strategies need to be implemented at the farm. The dryness of certain poultry environments is unfavorable for Campylobacter growth along with survival, but Campylobacter can enter into a viable, but non-culturable state (VBNC) to aid in survival. The aims of the current study were to evaluate the efficacy of five enrichment procedures for recovery of VBNC and determine the viability using a chick bioassay. The C. jejuni along with C. coli strain could not be recovered frequently after 2h of desiccation; however, they were shown to be VBNC using a chick bioassay. This is believed to be the first reports of the VBNC state after subjecting Campylobacter strains to dry-atmospheric-temperature stress and performing the chick bioassay using intracloacal administration of the samples containing VBNC cells. Campylobacter’s stress adaptive response within a dry poultry environment and correlation to survival may allow for additional interpretation on the epidemiology and ecology of this organism in poultry. Also, better resuscitation broths and methods are vital in order to accurately access the ecology of Campylobacter spp. in poultry.
Technical Abstract: The aims of the study were to evaluate the efficacy of 5 enrichment procedures for recovery of dry-atmospheric-temperature stressed C. jejuni and C. coli and determine the viable status of the non-culturable strains using a chick bioassay. Sterile chick paper pads (PP) and filter papers (FP) were inoculated at a low (L) and high (H) inoculum level. Inoculated samples were left at room temperature, exposed to atmospheric conditions for up to 24 h with sampling performed periodically. Recovery rate decreased gradually from 0 to 2 h and then sharply from 2 to 4 h. For the chick bioassay, negative dry-stressed samples at 6 and 24 h post-inoculation were administered orally and intracloacally to day-of-age chicks. Seven days post-inoculation, the chick’s ceca were analyzed for the marker strains. C. jejuni on the L-FP, H-FP, and H-PP were recovered from the chicks at a rate of 11%, 3%, and 6% respectively from 6 h samples but not recovered from 24 h old samples. C. coli on the L-FP, H-FP, L-PP, and H-PP were recovered from the chicks at a rate of 2%, 2%, 2% and 4% respectively from 6 h samples and 4% of the H-PP 24 h samples. This is the first study to report on the VBNC state after subjecting the strains to dry-atmospheric-temperature stress and also to utilize the intracloacal route of inoculation.