标题：Plasmid-Mediated Quinolone Resistance Genes and Antibiotic Residues in Wastewater and Soil Adjacent to Swine Feedlots: Potential Transfer to Agricultural Lands
摘要：Ba c k g r o u n d: Inappropriate use of anti biotics in swine feed could cause accelerated emergence of antibiotic resistance genes, and agricultural application of swine waste could spread antibiotic resis-tance genes to the surrounding environment.oB j e c t i v e s: We investigated the distribution of plasmid-mediated quinolone resistance (PMQR) genes from swine feedlots and their surrounding environment.Me t h o d s: We used a culture-independent method to identify PMQR genes and estimate their levels in waste water from seven swine feedlot operations and corresponding waste water-irrigated farm fields. Concentrations of (fluoro) quino lones in waste water and soil samples were determined by ultra-performance liquid chromatography–electrospray tandem mass spectrometry.re s u l t s: The predominant PMQR genes in both the waste water and soil samples were qnrD, qepA, and oqxB, whereas qnrS and oqxA were present only in waste water samples. Absolute concentrations of all PMQR genes combined ranged from 1.66 × 107to 4.06 × 108copies/mL in waste water and 4.06 × 106to 9.52 × 107copies/g in soil. Concentrations of (fluoro) quino lones ranged from 4.57 to 321 ng/mL in waste water and below detection limit to 23.4 ng/g in soil. Significant correlations were found between the relative abundance of PMQR genes and (fluoro) quino lone concentrations (r = 0.71, p = 0.005) and the relative abundance of PMQR genes in paired waste water and agricul-tural soil samples (r = 0.91, p = 0.005).co n c l u s i o n s: Swine feedlot waste water may be a source of PMQR genes that could facilitate the spread of antibiotic resistance. To our knowledge, this is the first study to examine the occurrence of PMQR genes in animal husbandry environments using a culture-independent method
