College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China; Center for Microbial Ecology, Michigan State University, East Lansing, MI 48824, USA.
College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China; Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Northwest A&F University, Yangling, Shaanxi 712100, China.
J Hazard Mater. 2018 Feb 15;344:716-722. doi: 10.1016/j.jhazmat.2017.11.020. Epub 2017 Nov 13.
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.
好氧堆肥广泛用于动物粪便的回收利用，它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）的粪便及其相应的堆肥，并通过高通量 qPCR 测试了多种 ARGs 和移动遗传元件（MGEs）。在粪便和堆肥样本中总共检测到 109 个 ARGs，这表明两者都是重要的 ARG 储存库。鸡粪和猪粪中的 ARGs 多样性和丰度明显高于牛粪，但工业堆肥对鸡粪中 ARGs 的减少效果优于猪粪和牛粪。堆肥普遍减少了一些 ARGs，但对来自不同类型动物粪便的其他 ARGs 的影响不一致。网络分析检测到 ARGs 和 MGEs 的广泛共存。floR、ermF、catB3、aac(6')-lb(akaaacA4)和 aadA 被鉴定为估计 ARGs 总丰度的合适指示基因。我们的研究结果表明，不同的动物种类对 ARGs 的多样性、丰度和持久性有显著影响，其中转座子的丰度、重金属浓度、总氮水平以及抗生素的剂量和暴露时间可能解释了这些差异。
