Abstract:
A total of a hundred and fifty Salmonella enterica isolated from poultry and swine representing 31 serovars were used in this study. Antibiotic susceptibility was examined and resistance pattern was analyzed. All the isolates were investigated for occurrence and characteristics of class 1 integrons. Localization of class 1 integrons and their transferability were assessed by conjugal experiment. The presence of Salmonella genomic islands were assessed. The S. enterica strains that were resistant to at least one of antibiotic were 86% and 59.3% was multidrug resistant. Two common resistance patterns found were the SPC-STR-SUL (6.21%) and the AMP-CHP-SPC-STR-SUL-TET-TRI (6.21%) phenotype. The intI1 gene was present in 25.6%, of which 55.5% carried gene cassettes with size ranging from 650 to 2,300 bp. Sequence analysis revealed 10 distinct Integrons profiles (IPs), in which genes blaPSE-1, dfrA1, dfrA12, aadA2, aadA4, silB, incompleted sat and incompleted codB were present in variable regions. The gene cassettes array dfrA1-orfC was most frequenly found among the isolates. Class 1 integrons were identified on conjugative plasmid in 7 Salmonella isolates. SGI1 variants (SGI1-A and SGI1-F) were present in 9 isolates belonging to serovars Albany, Emek, Kedougou and Kingston.
