Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen 361021, China; University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China.
Ecological Sciences, The James Hutton Institute, Dundee, DD2 5DA Scotland, UK.
Environ Int. 2020 Mar;136:105359. doi: 10.1016/j.envint.2019.105359. Epub 2020 Feb 6.
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.
畜牧业中抗生素的过度使用是普遍存在的，据信这会极大地促进动物体内抗生素耐药基因（ARGs）的选择。因此，全球范围内都在努力减少农业领域的抗生素使用。然而，减少牲畜生产中抗生素的使用是否能有效抑制 ARGs 的传播尚未得到证实。本研究采用微宇宙方法来确定添加抗生素水平降低或具有典型抗生素水平的粪便如何影响土壤、蚯蚓和叶际之间抗生素耐药基因的传播。与对照土壤相比，在常规粪便处理中，蚯蚓和叶际样本中的 ARG 丰度有更大的增加（P<0.05）。与对照相比，低抗生素粪便也会增加叶际和土壤中 ARG 的丰度，但不会增加蚯蚓肠道中的 ARG 丰度（P<0.05）。在土壤和蚯蚓肠道中，低抗生素粪便中 ARGs 的富集程度低于常规粪便。本研究表明，在使用家畜粪便施肥后，通过土壤-蚯蚓-叶际系统进行细菌转移是抗生素耐药基因在不同生境之间传播的一种潜在途径。
