Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology, Institute of Biotechnology, Beijing Academy of Agriculture and Forestry Sciences, No. 9 Shuguang Middle Road, Haidian District, Beijing, 100097, China.
College of Forestry, Northeast Forestry University, Harbin, 150040, China.
Environ Sci Pollut Res Int. 2023 Nov;30(52):112799-112812. doi: 10.1007/s11356-023-29975-8. Epub 2023 Oct 16.
The particle-size distribution of antimicrobial resistant (AMR) elements is crucial in evaluating their environmental behavior and health risks, and exposure to the fecal microbiome via particle mass (PM) is an important route of transmission of AMR from livestock to humans. However, few studies have explored the association between air and fecal AMR in farm environments from the perspective of particle-size stratification. We collected feces and PMs of different sizes from layer and broiler farms, quantified antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), and human pathogenic bacteria (HPB) using Droplet digital PCR (ddPCR), and analyzed the bacterial communities based on 16S rRNA sequencing. The particle-size distributions of 16S rRNA and AMR elements were similar and generally increased with larger particle sizes in chicken farms. In broiler farms, we observed a bimodal distribution with two peaks at 5.8-9.0 μm and 3.3-4.7 μm. The dominant airborne bacterial phyla were Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes. The dominant phyla in the feces were the same as those in the air, but the order of relative abundance varied. The particle-size distributions of specific bacterial genera differed between the animal-farm types. Overall, the degree of association between feces and different particulates increased with increasing particle size. The microbial communities in the coarse particles were similar to those in fecal samples. Escherichia coli, Staphylococcus spp., Campylobacter spp., and sul 2 (sulfonamide ARGs) tended to attach to small particles. We highlight the particle size-specific relationship between fecal and air microbes involving ARGs, MGEs, and HPB and provide valuable information for comprehensively assessing the transmission of fecal microorganisms through the airpath and its environmental and occupational health risks.
抗微生物药物耐药（AMR）元素的粒度分布对于评估其环境行为和健康风险至关重要，通过颗粒质量（PM）接触粪便微生物组是 AMR 从牲畜传播给人类的重要途径。然而，从颗粒尺寸分层的角度来看，很少有研究探讨农场环境中空气和粪便 AMR 之间的关联。我们从蛋鸡和肉鸡养殖场收集了不同大小的粪便和 PM，使用液滴数字 PCR（ddPCR）定量了抗生素耐药基因（ARGs）、移动遗传元件（MGEs）和人类病原菌（HPB），并基于 16S rRNA 测序分析了细菌群落。16S rRNA 和 AMR 元素的粒径分布相似，在鸡场中通常随着颗粒尺寸的增大而增大。在肉鸡养殖场中，我们观察到双峰分布，两个峰分别在 5.8-9.0 μm 和 3.3-4.7 μm 处。空气中主要的细菌门是厚壁菌门、变形菌门、放线菌门和拟杆菌门。粪便中的主要菌群与空气中的相同，但相对丰度的顺序不同。特定细菌属的粒径分布在动物养殖场类型之间存在差异。总体而言，粪便和不同颗粒之间的关联程度随着颗粒尺寸的增加而增加。粗颗粒中的微生物群落与粪便样本相似。大肠杆菌、葡萄球菌属、弯曲菌属和 sul 2（磺胺类 ARGs）倾向于附着在小颗粒上。我们强调了粪便和空气中微生物涉及 ARGs、MGEs 和 HPB 的粒径特异性关系，并为全面评估粪便微生物通过空气传播及其环境和职业健康风险提供了有价值的信息。
