摘要

       目标：
       在农场动物中大量使用抗生素有助于抗生素耐药基因（ARGs）在“一个健康”环境中的富集和传播。在家畜相关环境中发现了大量的精氨酸，但在中国的活禽市场（LPMs）中没有发现。
       方法：
       从我国18个省市的LPMs中采集753份家禽粪便样品，对130份样品进行了基因组测序。利用生物信息学工具构建基因图谱，分析ARG含量。采用PCR扩增和Sanger测序法对753份粪便标本中mcr-1基因的分布进行了检测。
       结果：
       我们发现，在家禽、人类和猪的肠道基因目录中，基因数量少，但基因功能共享率高。家禽肠道中含有539个精氨酸，可分为235种。家禽的精氨酸数量和丰度均显著高于猪和人。在所有130份标本中发现了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基因。此外，59.63%的LPM样品中含有大肠杆菌素抗性基因mcr-1，并发现了其他mcr基因变异。
       结论：
       我们证明，中国LPMs是ARGs的储存库，在这样一个贸易体系下，ARG从食用动物传播到人类的风险很高，这在以前是没有解决过的。

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.journalofinfection.com/article/S0163-4453(19)30097-0/fulltext