Antimicrobial resistance of <i>Salmonella</i> spp. recovered from raw chicken meat at abattoirs and retail markets in Jordan

Salmonella is a major causative factor of bacterial foodborne diseases in humans. This study aimed to investigate the antimicrobial vulnerability profiles and the presence of genes of antimicrobial resistance (AMR) among Salmonella spp. recovered from chilled raw chicken meat at chicken abattoirs and local markets in Jordan. Out of 700 samples, a total of 106 (15.14%) isolates tested were positive for Salmonella-(invA) gene: chicken carcasses collected from abattoirs (14.5%, 29/200) and retail markets (16.25%, 65/400) as well as chicken breast collected from retail markets (12.0%, 12/100). More than 98% of the isolates exhibited resistance to at least one antibiotic. Notably, the isolates showed high resistance toward ampicillin (75.5%) and amoxicillin/clavulanic acid (45.3%), sulfafurazole (66.0%), tetracycline (61.3%), and ciprofloxacin (42.5%). There was a lower level of resistance to cefotaxime (24.5%), chloramphenicol (19.8%), imipenem (11.3%), ceftazidime (9.4%), and gentamicin (7.5%). AMR profiling showed that 41.5% (n = 44) of isolates were multidrug resistant (MDR). The occurrence of blaTEM resistance gene (RG) was mostly prominent (92.5% (74/80)) among isolates resistant to ampicillin and those resistant to amoxicillin/clavulanic acid (52.1% (25/48)). Among 65 tetracycline-resistant Salmonella isolates, 89.2% (n = 58) harbored the tet(B) RG, and among 70 sulfonamide-resistant Salmonella spp., 38.6% (27/70) and 90.0% (63/70) of resistant isolates harbored sul1 and sul2 RG, respectively. The obtained results demonstrate the necessity to strictly control the usage of antibiotics in poultry to manage MDR Salmonella infections.