Effet des épandages de lisier de porc et du travail du sol sur la présence de gènes de résistance aux antimicrobiens dans le sol et l’eau de drainage en grandes cultures
Agricultural practices represent potential pathways for the propagation of antimicrobial resistance genes (ARGs) in the environment. Hog manure applications introduce antimicrobial resistant microorganisms to the soil. This study evaluated the impact of hog manure spreading and tillage practices on the presence of ARGs in soil and drainage water in field crops. Escherichia coli and enterococci bacteria were counted. After DNA extraction, tet(T), sul1 and blaCTX-M-1 resistance genes were quantified by qPCR. The detection of mcr-1 and mcr-2 genes was performed by conventional PCR. The results showed that high-dose manure application (45 m3/ha) had a long-term impact on tet(T) and sul1 genes abundance in soil. A dose of 20 m3/ha had a short-term impact. Gene abundance in drainage water decreased significantly 15 days after manure application for sul1 and 169 days for tet(T). Tillage practices did not have an impact on the presence and abundance of ARGs in samples. The blaCTX-M-1 genes were detected in hog manure and in 7 water samples, but no link was established with the treatments. The mcr-1 and mcr-2 genes were not detected. This study demonstrated that tetracycline and sulfonamide resistance genes reservoir in soil can be increased after repeated high doses swine manure applications.
Colistine Antimicrobial resistance Drainage water Liquid hog manure Antimicrobial resistance genes Tillage Tetracyclines beta-lactams Sulfonamides Colistin