摘要

       抗生素在北美家畜生产中的应用以及可能与可检测到的抗微生物基因（ARG）数量增加有关是一个日益令人关注的问题。采用实时定量PCR（RT-qPCR）技术，对艾伯塔省4个肉牛饲养场粪便复合物和捕集池样品中精氨酸的相对丰度和多样性进行了测定。此外，还收集了周边水路和城市污水处理厂的样本，以比较城市环境、淡水和饲养场的ARG剖面。检测了磺胺类、四环素类、大环内酯类、氟喹诺酮类、β-内酰胺类等5个抗生素家族18个耐药基因的相对丰度。废水处理样品中磺胺类、氟喹诺酮类和β-内酰胺类耐药基因占优势，而四环素类耐药基因占优势。这些结果反映了牛与人使用的抗生素类型，但其他因素，如ARG的共同选择和与这些样本相关的细菌群落组成的变化也可能起作用。

        The use of antibiotics in livestock production in North America and possible association with elevated abundance of detectable antimicrobial resistance genes (ARG) is a growing concern. Real-time, quantitative PCR (RT-qPCR) was used to determine the relative abundance and diversity of ARG in fecal composite and catch basin samples from 4 beef feedlots in Alberta. Samples from a surrounding waterway and municipal wastewater treatment plants were also included to compare the ARG profile of urban environments and fresh water with that of feedlots. The relative abundance of 18 resistance genes across 5 antibiotic families including sulfonamides, tetracyclines, macrolides, fluoroquinolones, and β-lactams was examined. Sulfonamide, fluoroquinolone, and β-lactam resistance genes predominated in wastewater treatment samples, while tetracycline resistance genes predominated in cattle fecal composite samples. These results reflect the types of antibiotic that are used in cattle versus humans, but other factors such as co-selection of ARG and variation in the composition of bacterial communities associated with these samples may also play a role.

         https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5764045/