Antimicrobial Resistance of E. Coli in Commercial Broiler

The antimicrobial resistance profile of E. coli isolates from cloacal and intestinal swabs of broilers in commercial poultry farms was studied. Susceptibility to nine antibiotic discs: amoxicillin (AML), clavulanic acid (CLA), enrofloxacin (ENR), gentamicin (GEN), oxytetracycline (OTC), trimethoprim (TMP), ciprofloxacin (CIP), doxycycline (DO) and tylosin (TYL) was tested on 50 isolates using the disc diffusion method (Kirby-Bauer). There was significant variance in the level of antibiotic efficiency, with the highest mean inhibition zone diameter recorded for Clavulanic Acid (20.21 mm) and the least for doxycycline (8.23 mm), suggesting high susceptibility and resistance. ANOVA indicated significant differences between antibiotics (F = 12.52, p < 0.000001), and Tukey’s HSD post hoc test confirmed that Clavulanic Acid performed the best against other drugs. Multidrug resistance (MDR) (resistance to three or more antibiotics) was detected in 64.6% of isolates, with serious consequences for animal and public health. The researchers concluded that the high levels of resistance combined with the plasmid-mediated transfer of resistance make resistance treatment in the poultry sector a priority for responsible antibiotic use, farm-level interventions, and continued research on resistance mechanisms, environmental determinants of resistance, and alternatives to antibiotics.