Gut microbiota play a central role in the health of animals. The bacteria that individuals acquire as they age may therefore have a profound effect on their future fitness. Since most birds are capable of flight, they can be widely distributed in and adapted to various ecosystems. Moreover, birds are also challenged by the need to digest a wide range of food resources in their guts. However, little is known regarding how the microbial community structure in birds, especially wild birds, changes with host age. Here, we used high-throughput sequencing of the 16S rRNA V3-V4 region to depict the microbial composition and structure in the adults and nestlings of Jankowski's bunting (Emberiza jankowskii), an endangered species of bird, during the breeding season. The results showed that the phyla Proteobacteria (52.45%), Firmicutes (13.87%), Bacteroidetes (5.76%), Actinobacteria (4.95%), Planctomycetes (4.36%), Euryarchaeota (3.20%), Acidobacteria (2.59%), Fusobacteria (2.24%), and Chloroflexi (1.8%) dominated the gut microbial communities in Jankowski's bunting. There was no significant difference in the alpha diversity and richness among different age groups. There was also no significant difference in species richness and diversity between the nestlings and adults. However, we observed different bacterial compositions at the genus level. The genera Photobacterium and Brochothrix were detected only in the nestling groups (at days 3, 6, and 9), while Diplorickettsia was detected only in the adult group. In summary, this study can provide additional information regarding the intestinal microorganisms of wild passerine and grassland birds and provide theoretical evidence for methods to protect Jankowski's bunting.

中文翻译：

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Jankowski 鹀 (Emberiza jankowskii) 肠道微生物群落结构的组成

肠道微生物群在动物健康中起着核心作用。因此，个人随着年龄增长而获得的细菌可能会对他们未来的健康产生深远的影响。由于大多数鸟类都能够飞行，因此它们可以广泛分布于各种生态系统中并适应各种生态系统。此外，鸟类还需要消化肠道中的各种食物资源。然而，关于鸟类，尤其是野生鸟类的微生物群落结构如何随着宿主年龄的变化而变化知之甚少。在这里，我们使用 16S rRNA V3-V4 区域的高通量测序来描述繁殖季节 Jankowski 鹀 (Emberiza jankowskii)（一种濒危鸟类）的成虫和雏鸟的微生物组成和结构。结果表明，变形菌门（52.45%）、厚壁菌门（13.87%）、拟杆菌 (5.76%)、放线菌 (4.95%)、浮游菌 (4.36%)、Euryarchaeota (3.20%)、酸杆菌 (2.59%)、梭杆菌 (2.24%) 和绿弯曲菌 (1.8%) 在 Jantingkowski 的肠道微生物群落中占主导地位. 不同年龄组的alpha多样性和丰富度没有显着差异。雏鸟和成鸟之间的物种丰富度和多样性也没有显着差异。然而，我们在属水平上观察到不同的细菌组成。光杆菌属和 Brochothrix 属仅在雏鸟组（第 3、6 和 9 天）中检测到，而双立克次体仅在成年组中检测到。总之，