DISSERTATION RESEARCH: Intra-annual Dynamics in the Gut Microbiota of Migratory Shorebirds

肠道微生物区系通过促进营养物质的吸收、解毒和与免疫系统的相互作用，在机体健康中发挥着至关重要的作用。虽然哺乳动物的微生物区系主要是由潜在的遗传决定的，但影响鸟类肠道微生物区系的因素在很大程度上仍然未知。迁徙的滨鸟对环境变化很敏感，因为它们在整个年度周期中使用了地理上分布广泛的栖息地。因此，当地环境有可能改变鸟类肠道微生物区系。这项研究将调查环境因素对迁徙滨鸟肠道微生物区系的影响，因为它们每年的长途迁徙和洲际迁徙使它们暴露在广泛的微生物和潜在病原体中。这项研究的首要目标是通过评估与繁殖、分期和越冬环境有关的肠道微生物区系年内变化的存在和原因，来评估当地环境在决定迁徙滨鸟肠道微生物区系组成方面的重要性。迁徙的滨鸟有可能成为远距离传播病原体的疾病媒介，调查肠道微生物区系的多样性和功能是确定当前和未来对鸟类和人类种群的疾病威胁的重要第一步。这项研究的总体目标将通过检验与环境-肠道微生物区系相互作用的不同方面相关的三个假设来实现：地点特征、停留时间和迁徙种群之间的相互作用。研究人员预测，当地环境在很大程度上决定了肠道微生物的组成，在这个环境中，纬度和羊群组成对肠道微生物区系组成的影响是可以检测到的。将从西半球关键的滨鸟寄生和越冬地点收集的粪便样本中分析滨鸟肠道微生物组成。细菌群落将使用基因技术进行测序，微生物群落将使用先进的生物信息学和贝叶斯统计框架进行分析。这项研究结合了迁徙生态学、微生物学和计算生物学的领域。

Gut microbiota plays a vital role in organism health through facilitating nutrient uptake, detoxification and interactions with the immune system. Whereas the mammalian microbiota is predominantly shaped by underlying genetics, factors affecting the avian gut microbiota remain largely unknown. Migratory shorebirds are sensitive to environmental change as a result of their use of geographically wide-spread habitats throughout their annual cycle. The local environment thus has the potential to alter avian gut microbiota. This research will investigate environmental factors influencing gut microbiota of migratory shorebirds as their long-distance movement and intercontinental migration annually expose them to a wide range of microorganisms and potential pathogens. The overarching objective of this study is to evaluate the importance of the local environment in determining gut microbiota composition in migratory shorebirds, by assessing presence and causes of intra-annual variation in gut microbiota in relation to breeding, staging and wintering environments. Migratory shorebirds have the potential to act as disease vectors that spread pathogens over long distances, and investigation of gut microbiota diversity and function is an essential first step towards identifying current and future disease threats to both avian and human populations. The overall objective of this research will be addressed by testing three hypotheses related to different aspects of environment-gut microbiota interactions: site characteristics, duration of stay, and interactions among migratory populations. The researchers predict that the local environment largely determines gut microbial composition, and that within this environment the effect of latitude and flock composition on gut microbiota composition will be detectable. Shorebird gut microbial composition will be analyzed from fecal samples collected from key shorebird staging and wintering sites throughout the Western Hemisphere. Bacterial communities will be sequenced using genetic techniques and microbial communities will be analyzed by using advanced bioinformatics and a Bayesian statistical framework. This research combines the fields of migration ecology, microbiology and computational biology.