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

肠道微生物群通过促进营养吸收、解毒和与免疫系统的相互作用在生物体健康中起着至关重要的作用。虽然哺乳动物的微生物群主要是由潜在的遗传学形成的，但影响鸟类肠道微生物群的因素在很大程度上仍然未知。候鸟对环境变化很敏感，因为它们在整个年度周期中使用地理上广泛分布的栖息地。因此，当地环境有可能改变鸟类肠道微生物群。这项研究将调查影响迁徙水鸟肠道微生物群的环境因素，因为它们的长途迁徙和洲际迁徙每年都会使它们暴露于各种微生物和潜在病原体。本研究的总体目标是评估当地环境在确定肠道微生物群组成的重要性，在迁徙的滨鸟，通过评估存在和肠道微生物群在繁殖，分期和越冬环境的年内变化的原因。迁徙的滨鸟有可能成为长距离传播病原体的疾病媒介，对肠道微生物群多样性和功能的调查是确定鸟类和人类当前和未来疾病威胁的重要第一步。本研究的总体目标将通过测试与环境-肠道微生物群相互作用的不同方面相关的三个假设来解决：站点特征，停留时间和迁移人群之间的相互作用。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，在这种环境中，纬度和羊群组成对肠道微生物群组成的影响将是可检测的。滨鸟肠道微生物组成将从西半球主要滨鸟阶段和越冬地点收集的粪便样本中进行分析。细菌群落将使用遗传技术进行测序，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。这项研究结合了迁移生态学，微生物学和计算生物学领域。

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.