Abstract: Wild boars(Sus scrofa), which are widely distributed in southern China, are one of the few large-hoofed species that populations are proliferating.In recent years, an increasing number of studies have been conducted on the intestinal microflora of wild animals, but none have investigated the intestinal microflora of the wild populations of S.scrofa.In this study, total DNA from the gastrointestinal tract(stomach, ileum, colon, and rectum) of four samples of free-living wild boars from the Miaoling Mountain area of Guizhou Province was extracted, and the V3-V4 region of the 16S rRNA gene was amplified using universal primer PCR.The amplification products were sequenced on an Illumina MiSeq platform to assess the community structure, diversity, and flora function of intestinal bacteria of wild boars.A total of 1 268 577 valid sequences remained after the results were filtered for quality, and the low-quality reads were discarded.After drawing out the minimum sample sequence number, 1 019 OTUs were identified at the 97% similarity level.All samples were categorized into 19 phyla and 292 genera.At the level of phylum classification, the key floras in the intestinal tract were Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria and there were 15 dominant genera, including Prevotella, Lactobacillus, Escherichia-Shigella, and Bifidobacterium.Rarefaction curves indicated that the sequencing depth had basically covered all bacteria in the sample.Among alpha diversity indices, the Chao1 and Shannon indices of the colon and rectum were significantly higher than those of the stomach and ileum(P<0.05).This fully confirmed that the colon and rectum had a bacterial community structure relatively similar and greater floral richness and diversity to that of the stomach and ileum.The results of principal coordinates analysis(PCoA) and analysis of similarity(Anosim) showed a readily visible difference in distinct parts of the gastrointestinal tracts of wild boars.LEfSe analysis indicated that there were 22 bacterial genera with significant differences in distinct intestinal segments of boars, most of which were attributed to Firmicutes.In addition, PICRUSt showed that different intestinal segments also had unique metabolic functions and pathways.This study preliminarily revealed the characteristics of the intestinal flora of wild boars from Guizhou Province.We found that the intestinal flora of wild boars had a relatively complex structure and that there were significant differences between distinct intestinal segments.

Key words: Sus scrofa, High-throughput sequencing, Gut microbiota, Bacterial diversity, Flora function, Guizhou Province

摘要： 野猪是当前南方山地森林生态系统中数量激增的主要有蹄类。为揭示贵州苗岭地区野猪肠道细菌的群落结构、多样性及菌群功能，本研究采用16S rRNA高通量测序技术检测了4头野猪胃肠道（胃、回肠、结肠和直肠）的细菌群落，共获得1 268 577条有效序列。经质控过滤，所有序列归类于1 019个OTU，包含19门292属。在门分类水平上，野猪肠道内核心菌群主要为厚壁菌门（Firmicutes）、拟杆菌门（Bacteroidetes）、变形菌门（Proteobacteria）和放线菌门（Actinobacteria），优势菌属包括普雷沃氏菌属（Prevotella）、乳酸杆菌属（Lactobacillus）、大肠-志贺氏菌属（Escherichia-Shigella）和双歧杆菌属（Bifidobacterium）等15个菌属。稀疏曲线表明测序深度已基本覆盖样品中所有细菌，测序充分。alpha多样性指数中，结肠和直肠的Chao1和Shannon指数显著高于胃和回肠（P<0.05），证明结肠和直肠比胃和回肠具有更高的菌群丰富度和多样性。主坐标分析（PCoA）和相似性分析（Anosim）结果也同样表明野猪不同肠道菌群结构具有显著差异。LEfSe分析表明在野猪不同肠段共有22个显著差异的细菌菌属，其中大部分都归属于厚壁菌门，并且PICRUSt分析显示不同的肠段也表现出独特的代谢功能和代谢途径。本研究初步揭示了野猪的肠道菌群特征，发现野生种群野猪肠道中具有相对复杂的菌群结构，且不同肠段间存在显著差异。

关键词: 野猪, 高通量测序, 肠道菌群, 细菌多样性, 菌群功能, 贵州