Roseline Olobatoke
North West University
South Africa
Title: Antibiotic resistance of non-typhoidal Salmonella strains isolated from broiler products in the North West Province of South Africa
Biography
Biography: Roseline Olobatoke
Abstract
This study was conducted to evaluate the resistance of non-typhoidal Salmonella strains (NTS), isolated from broiler products in the North West Province of South Africa, to antimicrobials. A total of 60 NTS isolates recovered from raw broiler products and confirmed by PCR were evaluated for antimicrobial resistance by disk diffusion method, using a panel of ten antibiotics. The NTS isolates that were identified and used in this study include S. typhimurium, S. enteritidis and S. newport. The antimicrobials used were ampicillin (10 µg), chloramphenicol (30 µg), ciprofloxacin (5 µg), amikacin (30 µg), trimethoprim-sulfamethoxasole (25 µg), tetracycline (30 µg) cefotaxime (30 µg), meropenem (10 µg), gentamicin (10 µg) and erythromycin (15 µg). Isolates resistant to ampicillin (n=48), tetracycline (n=60) and chloramphenicol (n=12) were further screened by PCR for antibiotic resistance genes, targeting the blaTEM, tet and cat genes. All the strains tested were resistant to two or more antibiotics. All isolates were susceptible to cefotaxime, meropenem, gentamycin and amikacin whereas all were resistant to tetracycline. Resistance to trimethoprim-sulfamethoxasole, ciprofloxacin and chloramphenicol was low, being 8.3%, 13.3% and 20% respectively. Multi-drug resistance was discovered in nine S. typhimurium strains, representing 15% of the tested isolates. In addition, the blaTEM gene was identified in 15 (31.3%) of the isolates screened, whereas the tet and cat genes were expressed in 12 (20%) and 6 (50%) resistant isolates respectively. The observations of this study indicate that NTS strains isolated from broiler products are resistant to multiple antibiotics, including quinolones.