摘要
      畜禽粪便是抗生素抗性基因（ARGs）传播到环境中的重要来源，对人类健康构成潜在威胁。在这里，我们研究了氟苯尼考（FF）和硫酚（TAP）在堆肥过程中的消散，以及它们对细菌群落、可移动遗传元素（MGE）和ARGs的影响。结果表明，FF和TAP在堆肥中迅速消散，半衰期分别为5.1和1.6d。然而，在堆肥过程中，FF不能完全去除。粪肥中的FF和TAP残留物可以减少堆肥过程中ARGs和MGEs的消除，并对堆肥的物理化学因素产生负面影响。floR和intI1之间存在显著相关性，表明粪肥中的floR更容易扩散到土壤环境中。同时，粪便中FF的存在可以增加floR的丰度。网络分析表明，变形菌门和厚壁菌门是携带ARGs的优势细菌群落和重要的潜在病原体宿主。土壤中FF的预测环境浓度超过100μg kg−1，这表明FF对自然环境构成潜在风险，我们通过现场实验验证了这一结果。结果表明，FF从粪肥迁移到土壤后，在土壤中消散。相比之下，粪肥中的TAP对环境的风险较低。这项研究强调，堆肥条件的改变可能会控制ARGs的去除率。需要进一步的研究来调查最佳的环境条件，以在堆肥过程中更快地降解FF和更全面地消除ARGs。
Abstract
Livestock manure is an important source of antibiotic resistance genes (ARGs) spreading to the environment, posing a potential threat to human health. Here, we investigated the dissipation of florfenicol (FF) and thiamphenicol (TAP), and their effects on the bacterial community, mobile genetic elements (MGEs), and ARGs during composting. The results indicated that FF and TAP dissipated rapidly in compost, with half-life values of 5.1 and 1.6 d, respectively. However, FF could not be completely removed during composting. The FF and TAP residues in manure could reduce the elimination of ARGs and MGEs during composting, and had a negative effect on the physicochemical factors of the compost. Significant correlations were found between floR and intI1, indicating that floR in manure may more easily diffuse to the soil environment. Meanwhile, the presence of FF in manure could increase the abundance of floR. Network analysis showed that Proteobacteria and Firmicutes were the dominant bacterial communities and important potential pathogen hosts carrying ARGs. The predicted environmental concentration of FF in the soil was over 100 μg kg−1, which indicates that FF poses a potential risk to the natural environment, and we verified this result through field experiments. The results showed that FF dissipated in the soil after it migrated from manure to soil. In contrast, TAP in manure posed lower environmental risk. This study highlights that changed in composting conditions may control the rate of removal of ARGs. Further studies are needed to investigate the best environmental conditions to achieve a faster degradation of FF and a more comprehensive elimination of ARGs during composting.

https://www.sciencedirect.com/science/article/abs/pii/S004896972203340X