Virulence Gene profiling in Salmonella Typhimurium Isolated from Fecal Samples of Domestic and Wild Animals

The virulence gene profile of twelve (12) Salmonella isolates obtained from faecal samples of animal origin, including livestock, primates and emu, was determined. All Salmonella isolates were identified by biochemical tests. Genus specific PCR further confirmed the Salmonella isolates revealing the expected bands of 496 bp. All isolates on serotyping were found to be Salmonella Typhimurium with antigenic structure 4, 2: i: 1, 2. These Salmonella isolates were screened for different virulence-associated genes by PCR-based procedures. All the isolates were positive for ssaQ, hilA, prgH and fljB genes. The mgtC gene was present in varying frequencies in isolates from different animal species with an overall frequency of 75%. By conventional PCR, it was demonstrated that the four genes, as indicators for salmonella pathogenicity islands (SPIs), were present in all strains, independently of the host species and outcome of infection.