Plasmid –mediated antimicrobial resistance bla CMY-2 gene and qnr (qnr A,qnr B and qnr S) genes in Salmonella isolated from human, animal and milk

This study was conducted to detect the bla CMY-2 gene and qnr genes ( qnr A, qnr B and qnr S) in Salmonella isolates from 278 different samples (50 direct milk samples, 50 indirect milk samples, 50 feces samples, 50 teat swab samples, 28 manual milk swabs and 50 stool samples) in Basrah province. The results showed that the percentage of Salmonella isolates in the samples was 6.1% by using API system and by PCR technique for identification. The highest resistance to Salmonella isolates were found against chloramphenicol and rifampin (100%). While all isolates were sensitive to ciprofloxacin . The use of plasmid treatment (Plasmid curing) by temperature method showed that 41.1% of total Salmonella isolates were associated with antimicrobial resistance of the plasmid. Plasmid analysis by molecular detection revealed that 11 isolates (64.7%) was positivity for bla CMY-2 while the qnr quinolone gene (A, B and S) was not detected in the isolates.