Amoxicillin / Clavulanic Acid and Cefotaxime Resistance in Salmonella Minnesota and Salmonella Heidelberg from Broiler Chickens

This study investigated the resistance of various Salmonella strains to betalactam antibiotics. Salmonella Minnesota (36 strains) and Salmonella Heidelberg (24 strains) were isolated from broiler chickens and carcasses by the Disk Diffusion Test and resistance genes blaCTX-M-8, blaACC-1 and blaCMY-2 were detected by PCR. Of the 60 strains tested, 80% were resistant to at least one antibiotic. Specifically, 66.7% were resistant to amoxicillin/clavulanic acid and 75% were resistant to cefotaxime. Among the amoxicillin/clavulanic acid resistant strains, the blaCMY-2 gene was detected in 40%, blaACC-1 in 37.5% and blaCTX-M-8 in 7.5%. Among the cefotaxime resistant strains, we detected the genes blaCTX-M-8 in 13.3%, blaACC-1 in 33.3%, and blaCMY-2 in 31.1%. The presence of cefotaximeand amoxicillin/clavulanic acid-resistant Salmonella in poultry, and the prevalence of extended spectrum betalactamases and AmpCbetalactamases in these strains are of huge concern to public health and economy.