摘要

    牲畜和家禽粪便中抗生素抗性基因（ARG）的日益流行引起了相当多的关注。但是，在实际的繁殖环境中，ARG传播的主要驱动力以及涉及的细菌仍不清楚。这项研究调查了147种动物粪便中的19种抗生素和4种重金属。结果表明，仔猪粪便中抗生素和重金属含量最高。进一步评估了12个ARG，4个移动遗传元件（MGE）和来自6个养猪场的仔猪粪便的细菌群落，以确定ARG传播的主要驱动因素和相关机制。磺胺类药物（SAs）解释了细菌群落变异的36.5％（P <0.05），并且与8个基因显着相关（P <0.01），这表明SAs主导了ARGs的传播，应接受严格监督。结构方程模型（SEM）表明，SAs通过两种途径增加了ARG的丰度：ARGs的水平转移（涉及10属）和ARGs的垂直转移（涉及26属）。这些结果提高了我们对参与ARGs传播的潜在宿主的了解，表明对上述潜在宿主的监测在动物饲养实践中也很重要。

    The increasing prevalence of antibiotic resistance genes (ARGs) in livestock and poultry faeces has attracted considerable amounts of attention. However, in the actual breeding environment, the key driver of the spread of ARGs and which bacteria are involved remain unclear. This study investigated 19 antibiotics and 4 heavy metals in 147 animal faeces. The results showed that piglet faeces exhibited the highest levels of antibiotics and heavy metals. Twelve ARGs, 4 mobile genetic elements (MGEs) and bacterial communities of piglet faeces from 6 pig farms were further assessed to determine the key driver and relevant mechanism of the spread of ARGs. Sulphonamides (SAs) explained 36.5% of the variance (P < 0.05) of the bacterial community and were significantly related to 8 genes (P < 0.01), indicating that SAs dominated the spread of ARGs and should be tightly supervised. Structural equation modelling (SEM) indicated that SAs increased the abundance of ARGs via two pathways: horizontal transfer of ARGs (involving 10 genera) and vertical transfer of ARGs (involving 26 genera). These results improve our understanding of the potential hosts involved in the spread of ARGs, suggesting that monitoring of the above potential hosts is also important in animal feeding practice.

    https://www.sciencedirect.com/science/article/abs/pii/S0304389420329484