Genetic analysis of multiple antimicrobial resistance in Salmonella isolated from diseased broilers in Egypt

Abstract

To date, no information has been available on the molecular bases of antimicrobial resistance in Salmonella spp. from poultry in Egypt or even in Africa. Therefore, the objective of this study was to analyze, at the molecular level, the mechanisms of multidrug-resistance in isolates of Salmonella recovered from diseased broilers in Egypt. Twenty-one Salmonella isolates were identified; 13 of these isolates were Salmonella enterica serovar Enteritidis and eight Salmonella enterica serovar Typhimurium. 17 (81%). Salmonella isolates displayed multidrug resistance phenotypes, particularly against ampicillin, streptomycin, spectinomycin, kanamycin, tetracycline, chloramphenicol, and trimethoprim/sulfamethoxazole. PCR and DNA sequencing identified class 1 integrons in nine (42.9%) isolates and class 2 integrons in three (14.3%) isolates. The identified resistance genes within class 1 integrons were aminoglycoside adenyltransferase type A, aadA1, aadA2 and aadA5 and dihydrofolate reductase type A, dfrA1, dfrA5, dfrA12, dfrA15 and dfrA17. The β-lactamase encoding genes bla TEM-1 and bla CMY-2 and florfenicol resistance gene floR were also identified. Furthermore, the tetracycline resistance gene tet(A) was identified in 14 (66.7%) Salmonella isolates. To the best of our knowledge, this is the first report of the molecular basis of antimicrobial resistance in Salmonella spp. isolated from poultry in Africa.

Characterization of Integrons and Resistance Genes in Salmonella Isolates from Farm Animals in Shandong Province, China

“…It is not approved for human use. In this study, floR was identified in 35.1% of Salmonella strains isolated from chickens, ducks and pigs, which was significantly higher than that reported in Egypt (1.0%) (Ahmed and Shimamoto, 2012). In addition, floR was identified in 90.0% of Salmonella strains isolated from pigs in this study.…”

Molecular Characterization of Multidrug Resistant Hospital Isolates Using the Antimicrobial Resistance Determinant Microarray

“…Although no dfr alleles were detected in the A. baumannii isolates, five E. coli and K. pneumoniae isolates were positive for the presence of at least one dfr gene; isolates N23 and N26 each harbored two different dfr genes. The alleles, dfrA5 , dfrA7 , and dfr12 - observed at high frequency in other studies of MDR isolates from this region [22], [41], [42], [43], [44] – were not found in the clinical strains tested here. However the other dfr alleles ( dfrA1 , dfrA15 , dfrA17 , and dfrA19 ) detected in our isolates have been well documented by others in various E. coli , K. pneumoniae , and Enterobacteriaceae isolates from this region [22], [41], [42], [43], [44], [45], [46], [47].…”

Occurrence of Salmonella enterica and Escherichia coli in raw chicken and beef meat in northern Egypt and dissemination of their antibiotic resistance markers

“…Another β-lactamase encoding gene bla CMY-2 , an AmpC beta-lactamase gene that confers resistance to a wide variety of β-lactam antibiotics detected in 13.3% of isolates. In contrast, in 4.7% of S. enterica serovars Typhimurium and Enteritidis originated from diseased broilers in Egypt bla CMY-2 was identified [ 48 ] and all resistant S. enterica serovar Typhimurium isolated from retail meat in US were harbouring bla CMY [ 49 ]. The same gene could not be detected previously in any S. enterica serovar Typhimurium isolated from chicken meat in Egypt [ 8 ].…”