Table_3_Comparative Analyses of Antibiotic Resistance Genes in Jejunum Microbiota of Pigs in Different Areas.xlsx

Antibiotic resistance genes (ARGs) are emerging environmental contaminants that threaten human and animal health. Intestinal microbiota may be an important ARGs repository, and intensive animal farming is a likely contributor to the environmental burden of ARGs. Using metagenomic sequencing, we investigated the structure, function, and drug resistance of the jejunal microbial community in Landrace (LA, Kunming), Saba (SB, Kunming), Dahe (DH, Qujing), and Diannan small-ear piglets (DS, Xishuangbanna) from different areas in Yunnan Province, China. Remarkable differences in jejunal microbial diversity among the different pig breeds, while the microbial composition of pig breeds in close areas tends to be similar. Functional analysis showed that there were abundant metabolic pathways and carbohydrate enzymes in all samples. In total, 32,487 ARGs were detected in all samples, which showed resistance to 38 categories of drugs. The abundance of ARGs in jejunum was not significantly different between LA and SB from the same area, but significantly different between DS, DH and LA or SB from different areas. Therefore, the abundance of ARGs was little affected by pig breeds and microorganism community structure, but it was closely related to geographical location. In addition, as a probiotic, Lactobacillus amylovorus is also an important ARGs producing bacterium. Our results revealed the antibiotic exposure and intestinal microbial resistance of farms in the study areas, which could provide basic knowledge and potential strategies for rational use of antibiotics and reducing the risk of ARGs transmission in animal husbandry.

抗生素抗性基因（Antibiotic resistance genes, ARGs）是一类新兴的环境污染物，对人类与动物健康构成威胁。肠道菌群可能是ARGs的重要储存库，而集约化养殖业则可能是ARGs环境负荷的重要来源。本研究采用宏基因组测序技术，对中国云南省不同地区的4个猪品种——长白猪（Landrace, LA，昆明）、撒坝猪（Saba, SB，昆明）、大河猪（Dahe, DH，曲靖）以及滇南小耳猪（Diannan small-ear, DS，西双版纳）的空肠微生物群落的结构、功能与耐药性进行了探究。研究发现，不同猪品种的空肠微生物多样性存在显著差异，而地理邻近地区的猪品种其微生物群落组成往往较为相似。功能分析显示，所有样本中均存在丰富的代谢通路与碳水化合物酶类。所有样本中共检测到32487个ARGs，可对38类药物产生抗性。同一地区的长白猪（LA）与撒坝猪（SB）的空肠ARGs丰度无显著差异，但滇南小耳猪（DS）、大河猪（DH）与异地的长白猪或撒坝猪的空肠ARGs丰度则存在显著差异。由此可见，ARGs丰度受猪品种与微生物群落结构的影响较小，但与地理位置密切相关。此外，作为一种益生菌，解淀粉乳杆菌（Lactobacillus amylovorus）同时也是一类重要的ARGs产生菌。本研究结果揭示了研究区域内养殖场的抗生素暴露情况与肠道微生物耐药性，可为畜牧业中合理使用抗生素以及降低ARGs传播风险提供理论基础与潜在策略。