|Koohmaraie, Mohammad - FORMER ARS EMPLOYEE|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: January 27, 2009
Publication Date: March 4, 2009
Citation: Harhay, D.M., Arthur, T.M., Bosilevac, J.M., Kalchayanand, N., Shackelford, S.D., Wheeler, T.L., Koohmaraie, M. 2009. Characterization of Multidrug-resistant Salmonella Isolated from Cull and Fed Cattle at Slaughter in the United States [abstract]. NCBA Beef Industry Safety Summit, San Diego, CA, March 4-6, 2009. Interpretive Summary: Interpretive Summary Not Required.
Technical Abstract: Contamination of beef with the foodborne pathogen Salmonella is an important issue for consumers and the beef processing industry. The emergence of multi-drug resistant (MDR) Salmonella also represents an important health problem as drug treatment options may become limited, especially for cases of invasive salmonellosis. Here we report the prevalence of MDR Salmonella associated with cull and fed cattle presented for slaughter in the United States. Our results show the average prevalence of Salmonella on hides, pre-evisceration and post-intervention carcasses was 89.6%, 50.2%, and 0.8% respectively. The proportion of the Salmonella population present on hides and carcasses found to be multi-drug resistant was on average 17.4%, 11.8%, and 0.33%, on hides, pre-evisceration and post-intervention carcasses, respectively. Hide and carcass levels of MDR Salmonella were not significantly different for fed or cull cattle slaughtered at the same abattoir. In this study, 16,218 Salmonella hide and carcass isolates were screened for drug resistance. Of these, 1009 (6.2%) MDR Salmonella isolates were identified. These MDR Salmonella were serotyped and determined predominantly to be serotypes Newport (45.8%), Typhimurium (15.0%), and Anatum (11.8%), however, serotypes Agona, Reading, Uganda, Muenster, and Dublin also were identified. Our results indicate that transportation and lairage of cattle likely affect the levels of MDR Salmonella present on the hides of cull and fed cattle at slaughter. We also observed regional differences with regard to MDR Salmonella prevalence. In spite of these differences, multiple hurdle processing interventions were quite effective and decreased carcass contamination with Salmonella on average by 98.4% (95% CI 97.6 to 99.7).