Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2007
Publication Date: 12/1/2007
Citation: Parveen, S., Taabodi, M., Mohamed, T., Schwarz, J.P., Oscar, T.P., Harter-Dennis, J., Hubert, S., White, D. 2007. Prevalence and Antimicrobial Resistance of Salmonella spp. Recovered from Processed Poultry. Journal of Food Protection. 70(11):2466-2472. Interpretive Summary: Salmonella contamination of chicken and contamination of chicken with Salmonella that are resistant to antibiotics are important food safety issues that were addressed in the current study. The current national average for Salmonella contamination of chicken carcasses is 12%. In the current study, the percentage of chicken carcasses contaminated with Salmonella was 88%. In the present study, Salmonella contamination was assessed using the whole broiler carcass as opposed to a small sample of carcass rinse. These results suggest that levels of Salmonella contamination on broiler carcasses may be under reported because the whole carcass is not being tested. Another important finding in the current study was that 80% of the Salmonella isolates from chicken carcasses were resistant to one or more antibiotics. Such antibiotic resistances are alarming because they could potentially increase the severity of human infections from Salmonella of chicken origin by causing clinical failure of antibiotic therapy. The latter finding supports current efforts to limit use of antibiotics on chicken farms and thus, curtail the current trend towards increased prevalence of Salmonella on chickens that are resistant to antibiotics used in human medicine.
Technical Abstract: This study determined the prevalence and antimicrobial resistance of Salmonella spp. recovered from processed poultry. Four hundred and eighty pre- or post-chill whole broiler carcasses were collected from a poultry processing plant between July 2004 and June 2005. In addition, water samples were collected at the entrance and exit of the chiller. After pre-enrichment, carcass and water samples were analyzed for the presence of Salmonella using the automated BAX system followed by traditional culture methods. The percentages of pre- and post-chill carcasses that were positive for Salmonella were 88.4 and 84.1, respectively. Ninety-two percent of water samples collected at the entrance of the chiller were positive for Salmonella compared to exit samples that all tested negative. Salmonella isolates were further serotyped and tested for antimicrobial resistance. Thirteen serotypes were identified, the most common being Kentucky (59.5%) and Typhimurium (17.8%). A total of 79.8% of isolates exhibited resistance to one or more tested antimicrobial agents. Resistance was most often observed to tetracycline (73.4%), ampicillin (52.9%), amoxicillin/clavulanic acid (52%), ceftiofur (51.7%), streptomycin (35.2%) and sulfisoxazole (21.8%). Sulfisoxazole and ceftiofur resistant S. Kentucky and Typhimurium isolates were further tested for class 1 integrons and blaCMY beta-lactamase genes by PCR, respectively. Sixty seven and 30% of S. Kentucky and Typhimurium isolates possessed blaCMY genes and class 1 integrons, respectively. These results indicate that a large number of Salmonella isolated from whole broiler carcasses display resistance to commonly used antimicrobials and class 1 integrons and blaCMY genes contribute to specific antimicrobial resistance phenotypes among Salmonella spp.