目标
农场动物大量使用抗生素促使“单一健康”环境中抗生素抗性基因（ARG）的富集和传播。在牲畜相关的环境中已发现了许多ARG，但在中国活禽市场（LPM）中并未发现。

方法
我们从中国18个省市的LPM中收集了753个家禽粪便样本，并对130个样本的基因组进行了测序。使用生物信息学工具构建基因目录并分析ARG含量。 PCR扩增和Sanger测序用于调查所有753份粪便样品中mcr-1基因的分布。

结果
我们发现家禽，人类和猪肠道基因目录之间共享的基因数量较少，但基因功能的百分比较高。家禽肠道内有539种ARG，分为235种类型。家禽的ARG数量和丰度均显着高于猪或人。在所有130个样本中发现了14种ARG类型，四环素抗性（TcR）基因是动物和人类中最丰富的ARG。此外，有59.63％的LPM样品中含有大肠菌素抗性基因mcr-1，还发现了其他mcr基因变异。

结论
我们证明了中国的LPMs是ARG的储存库，在这种贸易体系下，ARG从食用动物向人类的ARG传播面临很高的风险，这一问题以前从未得到解决。

Objectives
The heavy use of antibiotics in farm animals contributes to the enrichment and spread of antibiotic resistance genes (ARGs) in “one-health” settings. Numerous ARGs have been identified in livestock-associated environments but not in Chinese live poultry markets (LPMs).

Methods
We collected 753 poultry fecal samples from LPMs of 18 provinces and municipalities in China and sequenced the metagenomes of 130 samples. Bioinformatic tools were used to construct the gene catalog and analyze the ARG content. PCR amplification and Sanger sequencing were used to survey the distribution of mcr-1 gene in all 753 fecal samples.

Results
We found that a low number of genes but a high percentage of gene functions were shared among the poultry, human and pig gut gene catalogs. The poultry gut possessed 539 ARGs which were classified into 235 types. Both the ARG number and abundance were significantly higher in poultry than that in either pigs or humans. Fourteen ARG types were found present in all 130 samples, and tetracycline resistance (TcR) genes were the most abundant ARGs in both animals and humans. Moreover, 59.63% LPM samples harbored the colistin resistance gene mcr-1, and other mcr gene variants were also found.

Conclusions
We demonstrated that the Chinese LPMs is a repository for ARGs, posing a high risk for ARG dissemination from food animals to humans under such a trade system, which has not been addressed before.

https://www.sciencedirect.com/science/article/abs/pii/S0163445319300970