Characterization of Salmonella spp. and E. coli Strains Isolated from Wild Carnivores in Janos Biosphere Reserve, Mexico

Abstract

Enterobacteriaceae are considered one the most important zoonotic pathogens. In this study, we analyzed the characteristics of E. coli and Salmonella spp. strains present in carnivores from Janos Biosphere Reserve, Mexico. These microorganisms had been isolated from a wide range of domestic and free-range animals, including wild carnivores. Fifty-five individuals were sampled, and the presence of Salmonella and E. coli was determined by bacteriological standard methods. Strains isolated were characterized by molecular methods and in vitro infection assays. Eight different species of carnivores were captured, including coyotes (Canis latrans), gray fox (Urocyon cinereoargenteus), desert foxes (Vulpes macrotis), striped skunks (Mephitis mephitis), hooded skunks (Mephitis macroura), lynxes (Lynx rufus), raccoons (Procyon lotor), and badgers (Taxidea taxus). Salmonella spp. and E. coli were isolated from four species of carnivores. Five Salmonella spp. strains were isolated, and their molecular characterization revealed in three of them the presence of fimbrial and virulence genes associated with cell invasion. In vitro evaluation of these strains showed their capability to invade human Hep2 cells. Sixty-one E. coli strains were isolated; different serotypes and phylogroups were observed from these strains. Additionally, the presence of virulence genes showed differently.