Antibiotic resistance and the search for resistance and virulence genes in Escherichia coli strains isolated from agropastoral farms (Poultry, Cattle, and Fish) In Southern Benin

Resistance of animal-origin enterobacteria to antibiotics is experiencing a concerning global increase, with an escalating impact of extended-spectrum beta-lactamases (ESBL). Finding solutions to this problem requires reliable and diverse data. It is in this context that the present study was initiated to combat infections caused by Escherichia coli in agropastoral farms (poultry, cattle, and fish) in southern Benin. Samples consisting of cattle dung, poultry droppings, as well as water and sludge from fish farms were aseptically collected for various laboratory analyses. A total of 714 E. coli strains were isolated from 1,376 collected samples, with 434 strains from the Atlantique department and 280 strains from the Zou department. The isolation of strains was carried out according to the NF V08-050: 2009 standard. The identified strains were tested against various antibiotics using the Bauer and Kirby disk diffusion method on agar, as recommended by the WHO. Strains resistant to one or more antibiotics were selected for the search for resistance and virulence genes. Furthermore, multidrug resistance of the strains to antibiotics was also observed, particularly in the Beta-lactam class (100% resistance to AMC) and tetracyclines (90% resistance to tetracyclines). Additionally, genotypic detection revealed a total absence of virulence genes, whereas resistance genes such as beta-lactamase Sulfhydryl Variable (bla-SHV), beta-lactamase Temoniera (bla-TEM), and quinolone resistance gene B (qnrB) were more frequently detected at respectively 58%, 82% and 60%.