ARS | Publication request: Phylogenetic analysis of salmonella enteritidis isolates from poultry processing

Submitted to: International Poultry Scientific Forum
Publication Type: Abstract Only
Publication Acceptance Date: October 21, 2009
Publication Date: January 25, 2010
Citation: Liljebjelke, K.A., Clinkscales, III, R., Cason Jr, J.A., Ingram, K.D., Hinton Jr, A. 2010. Phylogenetic analysis of salmonella enteritidis isolates from poultry processing [abstract]. International Poultry Scientific Forum.

Technical Abstract: Salmonella enterica serotype Enteritidis is a cause of food borne illness historically associated with consumption of contaminated table eggs. S. Enteritidis has recently become more frequently isolated from broiler poultry carcasses, raising concern that this serotype may also become a cause of food borne illness associated with consumption of chicken products. Understanding the origins and entry of this human pathogen into integrated poultry production is crucial to identifying control points in the farm-to-fork production continuum. We tested the hypothesis that we could identify an endemic strain of S. Enteritidis associated with the poultry company studied, with the goal being to identify potential sources of the contamination. We used two different molecular techniques; pulsed-field gel electrophoresis (PFGE), and repetitive extragenic palindromic sequence - polymerase chain reaction (REP-PCR), to generate genetic fingerprints of S. Enteritidis isolates from samples collected in a commercial broiler chicken processing plant, and from broiler carcasses processed at this plant over a period of four months. The PFGE and REP-PCR genetic fingerprints were used to create phylogenetic trees in order to determine the relatedness of the strains. Antibiotic resistance profiles generated using a microbroth dilution method revealed that all isolates were pan-sensitive to the panel of antimicrobials tested. The phage types of the isolates were determined to be 8, 13, and 24, phage types commonly associated with food borne illness in the United States. Phylogenetic analysis revealed genetic diversity inconsistent with the hypothesis that these isolates originate from a single source within this poultry production system. This study provides data that contribute to understanding the epidemiology of S. Enteritidis in broiler poultry production.