Serotypes and Antimicrobial Resistance in Salmonella enterica Recovered from Clinical Samples from Cattle and Swine in Minnesota, 2006 to 2015

• Published in: PloS one Vol. 11; no. 12; p. e0168016
• Main Authors: Hong, Samuel, Rovira, Albert, Davies, Peter, Ahlstrom, Christina, Muellner, Petra, Rendahl, Aaron, Olsen, Karen, Bender, Jeff B, Wells, Scott, Perez, Andres, Alvarez, Julio
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 09-12-2016; Public Library of Science (PLoS)
• Subjects: Analysis; Animals; Anti-Bacterial Agents - pharmacology; Antibiotic resistance; Antibiotics; Antiinfectives and antibacterials; Antimicrobial agents; Antimicrobial resistance; Bacteria; Biology and Life Sciences; Bovidae; Cattle; Cattle - microbiology; Diagnostic systems; Drug resistance; Drug Resistance, Bacterial; Emergence; Epidemiology; Food; Food borne diseases; Food chains; Food production; Food sources; Foodborne diseases; Infections; Infectious diseases; Livestock; Medical laboratories; Medicine and Health Sciences; Microbial drug resistance; Microbial Sensitivity Tests; Minimum inhibitory concentration; Minnesota; Monitoring systems; Multidrug resistance; Population; Public health; Risk factors; Salmonella; Salmonella enterica; Salmonella enterica - classification; Salmonella enterica - drug effects; Salmonella enterica - isolation & purification; Salmonella typhimurium; Salmonellosis; Serotypes; Swine; Swine - microbiology; Trends; Veterinarians; Veterinary colleges; Veterinary medicine; Minnesota
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0168016

Salmonellosis remains one of the leading causes of foodborne disease worldwide despite preventive efforts at various stages of the food production chain. The emergence of multi-drug resistant (MDR) non-typhoidal Salmonella enterica represents an additional challenge for public health authorities. Food animals are considered a major reservoir and potential source of foodborne salmonellosis; thus, monitoring of Salmonella strains in livestock may help to detect emergence of new serotypes/MDR phenotypes and to gain a better understanding of Salmonella epidemiology. For this reason, we analyzed trends over a nine-year period in serotypes, and antimicrobial resistance, of Salmonella isolates recovered at the Minnesota Veterinary Diagnostic Laboratory (MVDL) from swine (n = 2,537) and cattle (n = 1,028) samples. Prevalence of predominant serotypes changed over time; in swine, S. Typhimurium and S. Derby decreased and S. Agona and S. 4,5,12:i:- increased throughout the study period. In cattle, S. Dublin, S. Montevideo and S. Cerro increased and S. Muenster became less frequent. Median minimum inhibitory concentration (MIC) values and proportion of antibiotic resistant isolates were higher for those recovered from swine compared with cattle, and were particularly high for certain antibiotic-serotype combinations. The proportion of resistant swine isolates was also higher than observed in the NARMS data, probably due to the different cohort of animals represented in each dataset. Results provide insight into the dynamics of antimicrobial resistant Salmonella in livestock in Minnesota, and can help to monitor emerging trends in antimicrobial resistance.