Resistance genetic testing and molecular typing of multidrug-resistant Staphylococcus aureus in poultry

Abstract:

[Background] Staphylococcus aureus is a Gram-positive bacterium that can become a pathogen causing an array of diseases in animals and people. [Objective] To understand the multiple drug resistant situation of poultry Staphylococcus aureus in different areas of Anhui Province, and its characteristics of drug resistance and genotyping. [Methods] Sick poultry livers collected from different areas of Anhui Province as inoculation materials. In total, 103 multiple drug-resistant strains of Staphylococcus aureus were isolated. Then the resistant genotypes and molecular typing of Staphylococcus aureus were detected by PCR and ERIC-PCR respectively. [Results] The strains were resistant to 3 to 8 antibiotics. Most strains demonstrated multi-drug resistance to 5 antibiotics (43/103), followed by 4 antibiotics (21/103) and 6 antibiotics (22/103). The drug resistance rate of Staphylococcus aureu to β-lactam was the highest (79.6%), followed by aminoglycosides (71.8%). The detection rate of drug resistance gene from high to low were mecA (92.2%), aac(6′)/aph(2″) (76.7%), ermC (37.9%), ermA (13.6%) and femA (3.9%). Six different groups were obtained by ERIC-PCR molecular typing, and the dominant epidemic flora was the group Ⅱ (38/103). [Conclusion] Drug resistant genes of aminoglycosides, β-lactam and macrolides had high detection rates. There were genetic diversities among avian Staphylococcus aureus in areas of Anhui Province according to molecular typing. There was no significant correlation between ERIC-PCR molecular typing and drug resistance spectrum.

Key words:Staphylococcus aureus (SA), drug resistance, multiple drug resistance, drug resistance gene, ERIC molecular typing