Abstract
BACKGROUND AND AIM: The spread of antimicrobial resistance (AMR) in the Enterobacteriaceae family represents a major global health problem for humans and animals. This study aimed to determine AMR levels and highlight the different resistance profiles of Enterobacteriaceae isolates collected from healthy broiler chickens in eastern Algeria. MATERIALS AND METHODS: A total of 200 cloacal swabs of healthy broilers from several poultry farms located in the Souk Ahras region (eastern Algeria) were collected. Samples were inoculated on MacConkey agar, and the isolated bacteria were identified using the API 20E system. Antimicrobial susceptibility testing was conducted using the disk diffusion method in accordance with the Clinical and Laboratory Standards Institute guidelines. The broth microdilution method was used to determine the minimum inhibitory concentration of colistin (CT). RESULTS: Two hundred and forty-one isolates of commensal Enterobacteriaceae were recovered, including: Escherichia coli (n = 194; 80.5%), Proteus mirabilis (n = 21; 8.71%), Escherichia fergusonii (n = 8, 3.32%), Salmonella spp. (n = 7, 2.9%), Enterobacter cloacae (n = 4, 1.66%), Klebsiella pneumoniae (n = 3, 1.25%), Serratia spp. (n = 3, 1.25%), and Kluyvera spp. (n = 1, 0.41%). High resistance rates were observed toward erythromycin (100%), doxycycline (96.68%), trimethoprim-sulfamethoxazole (95.85%), ciprofloxacin (94.19%), ampicillin (90.04%), kanamycin (78.01%), and amoxicillin-clavulanic acid (69.71%). However, moderate-to-low resistance rates were observed for CT (25.31%), ceftazidime (12.45%), and cefotaxime (8.71%). Interestingly, only two extended-spectrum beta-lactamase (ESBL)-producing E. coli isolates were detected. All isolates (100%) were multidrug-resistant (MDR), among which 58.92% were resistant to six and seven antibiotics. Forty AMR profiles were identified, reflecting a wide diversity of resistance with combinations of three to ten antibiotics. CONCLUSION: Our findings revealed alarming rates of AMR, highlighting the need to take measures to combat the phenomenon of AMR to protect animals and public health.