摘要

      抗生素抗性基因（ARG）丰度和微生物抗性（MR）常被用作污染风险的重要指标，但猪场废水中ARGs丰度与MR的关系尚不清楚。本研究采生猪养殖场废水、污水、上游河水、生活污水及下游河水样本。研究了20种ARGs亚型和2种整合子的浓度、最低抑菌浓度（MIC）和细菌群落。本研究共检测到20种ARGs和整合子亚型。20个亚型中17个亚型ARGs在生猪养殖废水中的含量最高，ermA的平均含量最高为108个拷贝/mL，最高可达2.41个拷贝/mL。MR与3种抗生素（环丙沙星、链霉素和四环素盐酸盐）的含量及其相应ARGs的丰度无显著相关性（P > 0.05），5个采样点ARGs共生菌和耐药共生菌的种类差异较大。猪场废水处理能有效降低3种抗生素的ARGs和MR。结果表明，猪场废水和周围河流中ARGs与MCR之间可能没有明显的相关性，这可能是由于各种环境因素所致，因此迫切需要对ARGs丰度与MR之间的关系进行综合评价。

       Antimicrobial resistance gene (ARG) abundance and microbial resistance (MR) are often used as important indicators of pollution risk; however, the relationship between ARGs abundance and MR in pig farm wastewater remains unknown. In this study, the raw pig farm wastewater, effluent water, upstream river water, domestic wastewater and downstream river water samples were collected. The concentration of 20 subtypes of ARGs and 2 integrons, minimal inhibit concentration (MIC), and bacterial communities were investigated. In this study, 20 subtypes of ARGs and integrons were detected in all sampling sites. The highest abundance of 17 of the 20 subtypes of ARGs was detected in raw pig farm wastewater, and ermA had the maximum average abundance of 10⁸ copies/mL, with up to 2.41 ± 0.12 × 10⁸ copies/mL. There was no significant correlation between MR to three antibiotics (ciprofloxacin, streptomycin and tetracycline hydrochloride) and the abundance of their corresponding ARGs (P > 0.05), and a large difference was detected between the types of ARGs co-occur bacteria and resistance co-occur bacteria in the 5 sampling sites. And the pig farm wastewater treatment (WWT) could effectively reduce the ARGs and MR to the 3 antibiotics. The results presented here show that there may be no obvious correlation between ARGs and MCR in pig farm wastewater and surrounding rivers, which may be due to various environmental factors, highlighting the urgent need for a comprehensive evaluation of relationship between ARGs abundance and MR.

       https://www.sciencedirect.com/science/article/abs/pii/S0147651319307833?via%3Dihub