BACKGROUND The early-life microbiota exerts a profound and lifelong impact on host health. Longitudinal studies in humans have been informative but are mostly based on the analysis of fecal samples and cannot shed direct light on the early development of mucosa-associated intestinal microbiota and its impact on GI function. Using piglets as a model for human infants, we assess here the succession of mucosa-associated microbiota across the intestinal tract in the first 35 days after birth. RESULTS Although sharing a similar composition and predicted functional profile at birth, the mucosa-associated microbiome in the small intestine (jejunum and ileum) remained relatively stable, while that of the large intestine (cecum and colon) quickly expanded and diversified by day 35. Among detected microbial sources (milk, vagina, areolar skin, and feces of sows, farrowing crate, and incubator), maternal milk microbes were primarily responsible for the colonization of the small intestine, contributing approximately 90% bacteria throughout the first 35 days of the neonatal life. Although maternal milk microbes contributed greater than 90% bacteria to the large intestinal microbiota of neonates upon birth, their presence gradually diminished, and they were replaced by maternal fecal microbes by day 35. We found strong correlations between the relative abundance of specific mucosa-associated microbes, particularly those vertically transmitted from the mother, and the expression levels of multiple intestinal immune and barrier function genes in different segments of the intestinal tract. CONCLUSION We revealed spatially specific trajectories of microbial colonization of the intestinal mucosa in the small and large intestines, which can be primarily attributed to the colonization by vertically transmitted maternal milk and intestinal microbes. Additionally, these maternal microbes may be involved in the establishment of intestinal immune and barrier functions in neonates. Our findings strengthen the notion that studying fecal samples alone is insufficient to fully understand the co-development of the intestinal microbiota and immune system and suggest the possibility of improving neonatal health through the manipulation of maternal microbiota.

中文翻译：

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母乳和粪便微生物指导猪新生儿肠道中粘膜相关微生物群和屏障功能的时空发育。

背景技术生命早期的微生物群对宿主健康产生深远的终生影响。人类的纵向研究信息丰富，但大多基于粪便样本的分析，无法直接揭示粘膜相关肠道微生物群的早期发育及其对胃肠道功能的影响。我们使用仔猪作为人类婴儿的模型，评估出生后 35 天内肠道内粘膜相关微生物群的演替情况。结果 尽管出生时具有相似的组成和预测的功能特征，但小肠（空肠和回肠）中的粘膜相关微生物组保持相对稳定，而大肠（盲肠和结肠）中的粘膜相关微生物组在第 35 天时迅速扩张和多样化。在检测到的微生物来源（牛奶、阴道、乳晕皮肤、母猪粪便、产仔栏和保温箱）中，母乳微生物主要负责小肠的定植，在分娩的前 35 天内贡献了大约 90% 的细菌。新生儿的生活。尽管母乳微生物在新生儿出生时为大肠微生物群贡献了超过 90% 的细菌，但它们的存在逐渐减少，并在第 35 天时被母体粪便微生物取代。我们发现特定粘膜相关微生物的相对丰度之间存在很强的相关性。微生物，特别是从母亲垂直传播的微生物，以及肠道不同部分的多种肠道免疫和屏障功能基因的表达水平。结论我们揭示了小肠和大肠肠粘膜微生物定植的空间特定轨迹，这主要归因于垂直传播的母乳和肠道微生物的定植。此外，这些母体微生物可能参与新生儿肠道免疫和屏障功能的建立。我们的研究结果强化了这样的观点，即仅研究粪便样本不足以充分了解肠道微生物群和免疫系统的共同发育，并表明通过操纵母体微生物群来改善新生儿健康的可能性。