Salmonella Enterica Serovar Typhimurium DT104 Invasion is Not Enhanced by Sub-Inhibitory Concentrations of the Antibiotic Florfenicol
- *Corresponding Author:
- Dr. Brian Brunelle, PhD
Food Safety and Enteric Pathogens Research Unit
National Animal Disease Center
P.O. Box 70, Ames, IA 50010- 0070
E-mail: [email protected]
Received date: February 11, 2011; Accepted date: March 04, 2011; Published date: March 08, 2011
Citation: Brunelle BW, Bearson SMD, Bearson BL (2011) Salmonella Enterica Serovar Typhimurium DT104 Invasion is Not Enhanced by Sub-Inhibitory Concentrations of the Antibiotic Florfenicol. J Veterinar Sci Technol 2:104. doi:10.4172/2157-7579.1000104
Copyright: © 2011 Brunelle BW, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The incidence of multi-drug resistant Salmonella has increased globally over the past several decades and has become a major public health concern. Isolates of Salmonella enterica serovar Typhimurium DT104 are resistant to five or more antibiotics, including florfenicol, and have been associated with enhanced virulence in livestock and humans. Because sub-inhibitory concentrations of some antibiotics have been found to modulate invasion of certain bacteria under specific conditions, the effect of florfenicol on S. Typhimurium DT104 invasion was evaluated. Three clinical bovine isolates were exposed to sub-inhibitory concentrations of florfenicol for 30 minutes to establish the initial response to the antibiotic. HEp-2 cellular invasion assays, as well as expression analyses of invasion-related genes, demonstrated that the invasiveness of the S. Typhimurium DT104 isolates was not enhanced after exposure to sub-inhibitory concentrations of florfenicol. These results suggest that cattle and swine can be treated with florfenicol for respiratory illness without exacerbating Salmonella Typhimurium DT104 virulence in carrier animals.