摘要     

抗生素在畜牧业中的过度使用被认为是导致动物抗药性基因（ARGs）选择的重要原因。因此，全球正在努力减少抗生素在农业生产上的使用。然而，目前还没有确定在畜牧业生产中减少抗生素的使用是否能有效地减少ARGs的传播。本文采用微观方法通过在肥料中添加低水平的抗生素或常规水平的的抗生素来确定对土壤、蚯蚓和叶状圈之间抗生素抗性基因传播的影响。与对照土壤相比，蚯蚓和叶状圈样品在常规施肥处理中的ARG丰度增加幅度较大（P<0.05）。与对照相比，降低抗生素水平的肥料也增加了叶状圈和土壤中的ARG含量，但没有增加蚯蚓肠道中的ARG含量（P<0.05）。在土壤和蚯蚓肠胃中，降低抗生素水平的肥料中ARGs的富集率均低于常规肥料。本研究发现，土壤-蚯蚓-叶状圈系统中的细菌性转移是利用家畜粪便施肥后在栖息环境间传播ARG的潜在途径。

The overuse of antibiotics in animal husbandry is widespread and believed to significantly contribute to the selection of antibiotic resistance genes (ARGs) in animals. Thus, there is a global drive to reduce antibiotic use in the agricultural sector. However, it has not been established whether a reduction in the use of antibiotics in livestock production would be effective in reducing the spread of ARGs. A microcosm approach was used to determine how the addition of manure with either reduced antibiotic levels or with typical antibiotic levels could affect the spread of antibiotic resistance genes between soil, earthworms and the phyllosphere. When compared to the control soil, earthworm and phyllosphere samples had the greater increase in ARG abundance in conventional manure treatments (P < 0.05). Reduced antibiotic manure also enriched the abundance of ARGs in the phyllosphere and soil but not earthworm guts when compared to the control (P < 0.05). In both soil and earthworm guts, the enrichment of ARGs was lower in reduced antibiotic manure than in conventional manure. This study has identified bacterial transfer through the soil-earthworm-phyllosphere system as a potential means to spread ARGs between habitats after fertilization with livestock derived manures.

https://www.sciencedirect.com/science/article/pii/S0160412019332969