Author
Line, John | |
Oakley, Brian | |
STERN, NORMAN - Former ARS Employee |
Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/1/2013 Publication Date: 1/15/2013 Citation: Line, J.E., Oakley, B., Stern, N. 2013. Comparison of cumulative drip sampling to whole carcass rinses for estimation of Campylobacter spp. and quality indicator organisms associated with processed broiler chickens . Poultry Science. 92(1):218-24. Interpretive Summary: The whole carcass rinse (WCR) procedure is routinely used as a sampling method for determining the presence and number of quality-indicator organisms and pathogens associated with broiler chicken carcasses in processing facilities. Collection of a cumulative drip sample by placing collection vessels under the processing line could potentially capture a more representative sample of bacterial populations associated with an entire flock with less labor than individual bird rinses. The purpose of this study was to evaluate a cumulative drip sampling method for recovery of Campylobacter spp. and three types of quality indicator organisms from broiler carcasses. Samples were collected on 14 days from a commercial broiler processing facility over a three month period. WCR samples were obtained post-evisceration (PEWCR) and post-chill (PCWCR) and drip samples were obtained by placing multiple collection vessels at appropriate points post-evisceration, pre-chill, and post-chill on each collection day for approximately 1 h or until an entire flock of about 15K birds had passed. Campylobacter spp. were counted by traditional direct plating techniques. Total viable bacteria, Enterobacteriaceae, and E. coli populations were determined using the Tempo automated MPN instrument. Pyrosequencing was performed on selected samples in order to take a census of the WCR and drip samples. No statistically significant difference was demonstrated between the WCR and cumulative drip sampling methods in recovery of Campylobacter spp., total viable bacteria, Enterobacteriaceae or E. coli associated with the post-evisceration or post-chill samples (P>0.02). There were no significant correlations between any of the indicator organisms and Campylobacter spp. for any sample type. Analyses of the pyrosequencing census data showed each bird had different bacterial communities and suggested cumulative sampling may be required to obtain an accurate census of pathogenic bacteria from a whole flock. The cumulative drip sampling technique may be useful in providing a more representative summary of process control in poultry processing facilities. Poultry producers and scientists in research and regulatory positions will find this information useful. Adoption of this technique could lead to labor-savings and a better method for insuring microbiological safety of processed poultry. Technical Abstract: The whole carcass rinse (WCR) procedure is routinely used as a sampling method for determining the presence and number of quality-indicator organisms and pathogens associated with broiler chicken carcasses in processing facilities. Collection of a cumulative drip sample by placing collection vessels under the processing line could potentially capture a more representative sample of bacterial populations associated with an entire flock with less labor than individual bird rinses. The purpose of this study was to evaluate a cumulative drip sampling method for recovery of Campylobacter spp. and three types of quality indicator organisms from broiler carcasses. Samples were collected on 14 days from a commercial broiler processing facility over a three month period. WCR samples were obtained post-evisceration (PEWCR) and post-chill (PCWCR) and drip samples were obtained by placing multiple collection vessels at appropriate points post-evisceration, pre-chill, and post-chill on each collection day for approximately 1 h or until an entire flock of about 15K birds had passed. Campylobacter spp. were counted by traditional direct plating techniques. Total viable count, Enterobacteriaceae, and E. coli populations were determined using the Tempo automated MPN instrument. Pyrosequencing of broad-range bacterial 16S rRNA PCR products was performed on selected samples in order to take a comprehensive census of each sample and compare the WCR and drip samples. No statistically significant difference was demonstrated between the WCR and cumulative drip sampling methods in recovery of Campylobacter spp., total aerobes, Enterobacteriaceae or E. coli associated with the post-evisceration or post-chill samples (p>0.02). There were no significant correlations between any of the indicator organisms and Campylobacter spp. for any sample type. Analysis of the pyrosequencing census data showed high inter-bird variability and suggested cumulative sampling may be required to obtain fully representative sampling of a flock. For most bacterial taxa, relative abundance in individual carcass rinses was correlated with cumulative drip samples, but some taxa, including two putative pathogens, were under-counted or missed entirely by individual bird rinses. Individual carcass rinses may not be representative of the flock microbial community. The cumulative drip sampling technique may save labor and provide a more representative summary of process control in poultry processing facilities. |