Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/5/2013
Publication Date: 11/1/2013
Citation: Trimble, L., Alalli, W., Gibson, K., Ricke, S., Crandall, P., Jaroni, D., Berrang, M.E., Habteselassie, M. 2013. Prevalence and concentration of Salmonella and Campylobacter in the processing environment of small-scale pastured broiler farms. Poultry Science. 92(11):3060-3066.. Interpretive Summary: Locally grown food, including poultry, is a growing niche market. Many small broiler chicken producers that grow for local sale conduct slaughter and process operations on the farm. In small on-farm poultry processing operations, processing offal (inedible parts) and water are disposed of on the farm as run off or compost. It is unknown how such disposal may affect the prevalence of poultry associated human pathogens such as Campylobacter and Salmonella in the local environment. In this study, processing waste water, surrounding soil and compost piles (including inedible chicken) at four small poultry growing and processing operations were tested for the presence and numbers of Campylobacter and Salmonella. Campylobacter was detected in approximately 64% of 42 soil and 39 compost samples and in approximately 46% of 46 waste water samples. Waste water had a significantly lower number of Campylobacter per g than did soil or compost. Salmonella was detected in 60% of soil, 64% of compost and 48% of waste water samples. All types of samples had about the same number of Salmonella per g. These data show that human pathogens can be found in the environment around small on-farm slaughter and processing operations. This represents a potential for spread of these bacteria to other poultry raised on the same farm in addition to other farm animals, humans and the environment. These data have implications relative to disposal of small scale on-farm poultry processing waste. More research is needed to develop practices to deal with this waste.
Technical Abstract: A growing niche in the locally grown food movement is the small scale production of broiler chickens using the pasture-raised poultry production model. Little research exists that focuses on Salmonella and Campylobacter contamination in the environment associated with on-farm processing of pasture-raised broilers. The objective of this study was to establish baseline data of Salmonella and Campylobacter prevalence and concentration in soil and mortality compost resulting from prior processing waste disposal in the small-scale, on-farm broiler processing environment. Salmonella and Campylobacter concentrations were determined in soil (n=42), compost (n=39), and processing wastewater (PWW; n=46) samples using a 3-tube Most Probable Number (MPN) method for Salmonella and direct plating method for Campylobacter according to the United States Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) protocols. Salmonella prevalence and concentration (mean log10 MPN) in soil (60%, 0.97 [95% CI: 0.66-1.27]), compost (64%, 0.95 [95% CI: 0.66-1.24]), and wastewater (48%, 1.29 [95% CI: 0.87-1.71]) were not significantly different (P>0.05). Campylobacter prevalence was not significantly different by sample type (64.3%, 64.3%, and 45.7% in soil, compost, and PWW, respectively). However, the concentration (mean log10 CFU) of this pathogen was significantly lower (P<0.05) in wastewater (2.19 [95% CI: 0.36-3.03]) samples compared to soil (3.08 [95% CI: 2.23-4.0]), and compost (3.83 [95% CI: 2.71-4.95]). The current study provides insight into small-scale poultry production waste disposal practices and provides a record of data which may serve as a guide for future improvement of these practices. Further research is needed regarding the small-scale broiler production environment in relation to potential disposal intervention methods.