摘要
      抗生素耐药性基因（ARGs）的传播已成为全球公共卫生关注的问题。然而，ARGs，特别是高危ARGs在水产养殖动物肠道中的分布和影响因素尚不清楚。在这里，我们使用16S rRNA基因测序和高通量定量PCR技术来确定从中国主要小龙虾养殖省份的40个养殖池中收集的小龙虾肠道微生物群和ARGs。我们在小龙虾肠道中检测到74个ARGs。其中，β-内酰胺酶和四环素抗性基因占优势。ARG总量在湖北省最高。在小龙虾肠道中也发现了高风险ARGs，ermB的丰度最高，分布在安徽、湖北、河南和江西省。此外，机会性病原体（链球菌、气单胞菌和不动杆菌）可能是ARGs的潜在宿主，包括高危ARGs。最后，栖息地、环境因素（NO3-N、pH和温度）、微生物α多样性和可移动遗传元素（MGE）对ARGs图谱显示出显著影响。总的来说，我们的研究结果表明，ARGs在小龙虾肠道中普遍存在，可能对人类健康构成潜在风险，这将有助于制定有针对性的策略，对水产养殖中的ARGs进行风险管理和评估。
Abstract
The propagation of antibiotic resistance genes (ARGs) has become a global public health concern. However, the distribution and influencing factors of ARGs, especially high-risk ARGs, in the gut of aquaculture animals remain unclear. Here, we employed 16S rRNA gene sequencing and high-throughput quantitative PCR techniques to determine crayfish gut microbiota and ARGs collected from 40 culture ponds in major crayfish farming provinces of China. We detected 74 ARGs in crayfish gut. Among them, the beta-lactamase and tetracycline resistance genes were dominant. The total ARG abundance was the highest in Hubei Province. High-risk ARGs were also found in crayfish gut, and ermB had the highest abundance and distributed in Anhui, Hubei, Henan and Jiangxi Province. In addition, opportunistic pathogens (Streptococcus, Aeromonas and Acinetobacter) might be potential hosts for ARGs, including high-risk ARGs. Finally, habitat, environmental factors (NO3-N, pH and temperature), microbial alpha diversity and mobile genetic elements (MGEs) showed significant influence on ARGs profiles. Generally, our results illustrate that ARGs are prevalent in crayfish gut and may pose potential risk to human health, which will help develop targeted strategies for the risk management and assessment of ARGs in the aquaculture.

https://www.sciencedirect.com/science/article/abs/pii/S0048969722067110