基于时序网络动力学的围产期奶牛与犊牛肠道菌群稳态变化、定植及垂直传递特征的分析

本研究旨在阐明母体干预调节犊牛初始菌群定植及菌群间相互作用的动态变化，为揭示早期生命中潜在的菌群差异对犊牛后续健康的影响提供理论基础。研究证明，生物子代不但遗传了母体的DNA，同时也遗传了母体的微生物组群。但有关奶牛在分娩前后肠道菌群稳态变化，犊牛肠道菌群来源和定植时间，母牛微生物组群传递特征均未见文献报道。时序网络动力学在微生物静态网络中加入时间维度，将横截面研究扩展为时间动态研究。通过非线性微分方程动力学模型的建立，可准确确定母牛垂直传递到犊牛的肠道菌群关键菌属。本研究以母牛围产期及其所产犊牛早期生长发育阶段为时间序列，利用共现相关网络、交互网络和随机森林衍生模型等方法，描述孕期母牛肠道微生物菌群的稳态变化及其犊牛肠道菌群的母源传递特征，拟合新生犊牛肠道菌群的定植过程，确定母子微生物传递的关键菌属，为未来通过干预孕期母牛肠道微生态，提高其子代肠道健康、生长发育和未来泌乳潜力奠定基础。

Abstract: The object of this study is to clarify the the dynamic changes of initial bacterial colonization and interactions in calf intestinal microflora by maternal intervention and regulation, therefore, providing a theoretical basis for revealing the influence of potential microflora differences in early life on the follow-up health of calves.It has been proved that biological offspring not only inherit the DNA, but also the microbiome from maternal. However, studies that focus on the steady-state changes of the intestinal microflora before and after calving, the source and the colonization time of the intestinal flora in calves, and the transmission characteristics of microflora of cows are limited. Time series network dynamics, which adding time dimension to the static microbial network, expands cross sectional study to time motion study. Intestinal microflora vertically transferred from cow to calf can be determined by establishing nonlinear differential dynamic models. This study will take the perinatal period of cow and the early growth and development of calves as time series,using co-occurrence correlation networks, interactive networks, and random forest-derived models to describe the the steady-state changes of the intestinal microflora in pregnant cows and the maternal transmission characteristics to calves. Then, the colonization process of intestinal flora in newborn calves are fitted, and the key genus transmitted from cow to calf are determined. The results of this study will lay a theoretical foundation for promoting the growth and intestinal health of pregnant cows and calves.