摘要

好氧堆肥广泛用于畜禽粪便的循环利用，可以减少进入环境的抗生素抗性基因( ARGs )的数量。我们从12个大型农场采集了三种动物（牛，鸡和猪）粪肥和相应的堆肥，并通过高通量qPCR测试了多种ARG和移动遗传元件（MGE）。在粪便和堆肥样品中总共检测到109个ARG，从而表明这两者都是重要的ARG库。鸡粪和猪粪中ARG的多样性和丰富度明显高于牛粪，但工业堆肥对降低鸡粪中ARG的效果优于猪粪和牛粪。堆肥普遍减少了一些ARG，但对不同类型动物粪便中的其它ARG的影响不一致。网络分析发现，ARGs和MGEs普遍同时发生。floR、ermF、cat3、AAC ( 6′) - lb ( aaaaca4 )和aadA被鉴定为估算ARGs总丰度的合适指示基因。我们的研究结果表明，不同动物物种对ARGs的多样性、丰度和持久性有显著影响，转座子的丰度、重金属浓度、总氮水平以及抗生素暴露的剂量和持续时间可以解释这些差异。

Aerobic composting is used widely for animal manure recycling, and it may reduce the amount of antibiotic resistance genes (ARGs) that enter the environment. We sampled three types of animal (bovine, chicken, and pig) manure and the corresponding composts from 12 large-scale farms, and tested multiple ARGs and mobile genetic elements (MGEs) by high-throughput qPCR. A total of 109 ARGs were detected in the manure and compost samples, thereby demonstrating that both are important ARG reservoirs. The diversity and abundance of ARGs were significantly higher in chicken and pig manure than bovine manure, but industrial composting was more efficient at reducing the ARGs in chicken manure than pig and bovine manure. Composting universally reduced some ARGs, but inconsistently influenced other ARGs from different types of animal manures. Network analysis detected the widespread co-occurrence of ARGs and MGEs.floR, ermF, catB3, aac(6′)-lb(akaaacA4), and aadA were identified as suitable indicator genes for estimating the total abundance of ARGs. Our results suggest that different animal species had significant effects on the diversity, abundance, and persistence of ARGs, where the abundance of transposons, heavy metal concentration, total nitrogen level, and the dosage and duration of exposure to antibiotics may explain these differences.

https://www.sciencedirect.com/science/article/pii/S0304389417308427