Characterization of Virulence Genes among Multidrug Resistant Salmonellae Isolated from Chickens.

Multidrug resistant (MDR) pathogenic Salmonella species augment the frequency and severity of infection lead to treatment failure in both animals and humans. Occurrence of virulence determinant genes in MDR Salmonella species still lack and need more investigations. Therefore, this study was undertaken to find out the prevalence of MDR salmonellae and their virulence genes in diseased broiler. Thirty out of three hundred (10%) of chicken organs were infected with salmonellae. Salmonella. Typhimurium, S. Enteritidis, S. Birkenhead, S. Virchow, S . Kentucky, S . Arizona and S . Montevideo represented 46.7%, 20%, 3.3%, 3.3%, 10%, 10% and 6.7% of the examined serotypes, respectively. Antimicrobial susceptibility test of all salmonella isolates revealed that all salmonella isolates were sensitive to ciprofloxacin and chloramphenicol. Meanwhile, they were resistant to erythromycin, rifamycin and amoxicillin/clavulinic acid.  S . birkenhead and S . typhimurium were the most resistant phenotypes. PCR results showed fli C and sef C genes were detected in Salmonella typhimurium and Salmonella Enteritidis, respectively. Furthermore, inv A, hil A, stn , sop B, pef A and spv C genes with percentages 100%, 88%, 53%, 41%, 41%  and 6% among examined serotypes respectively. It could be concluded that multidrug resistant salmonellae contain at least one virulence gene.