Department of Biology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, UK.
Office of Science and Technology Policy, Executive Office of the President, 1650 Pennsylvania Avenue, Washington, DC, 20504, USA.
Sci Rep. 2024 Aug 2;14(1):17933. doi: 10.1038/s41598-024-66460-9.
The microbiome is a key factor in the health, well-being, and success of vertebrates, contributing to the adaptive capacity of the host. However, the impact of geographic and biotic factors that may affect the microbiome of wild birds in polar environments is not well defined. To address this, we determined the bacterial 16S rRNA gene sequence profiles in faecal samples from pygoscelid penguin populations in the Scotia Arc, focusing on gentoo penguins. This mesopredatory group breeds in defined colonies across a wide geographic range. Since diet could influence microbiome structure, we extracted dietary profiles from a eukaryotic 18S rRNA gene sequence profile. The bacterial microbiome profiles were considered in the context of a diverse set of environmental and ecological measures. Integrating wide geographic sampling with bacterial 16S and eukaryotic 18S rRNA gene sequencing of over 350 faecal samples identified associations between the microbiome profile and a suite of geographic and ecological factors. Microbiome profiles differed according to host species, colony identity, distance between colonies, and diet. Interestingly there was also a relationship between the proportion of host DNA (in relation to total 18S rRNA gene signal) and the microbiome, which may reflect gut passage time. Colony identity provided the strongest association with differences in microbiome profiles indicating that local factors play a key role in the microbiome structure of these polar seabirds. This may reflect the influence of local transfer of microbes either via faecal-oral routes, during chick feeding or other close contact events. Other factors including diet and host species also associate with variation in microbiome profile, and in at least some locations, the microbiome composition varies considerably between individuals. Given the variation in penguin microbiomes associated with diverse factors there is potential for disruption of microbiome associations at a local scale that could influence host health, productivity, and immunological competence. The microbiome represents a sensitive indicator of changing conditions, and the implications of any changes need to be considered in the wider context of environmental change and other stressors.
微生物组是脊椎动物健康、幸福和成功的关键因素，有助于宿主的适应能力。然而，地理和生物因素对极地环境中野生鸟类微生物组的影响尚不清楚。为了解决这个问题，我们确定了斯科舍弧（Scotia Arc）小企鹅种群（以巴布亚企鹅为例）粪便样本中的细菌 16S rRNA 基因序列图谱。这个中型捕食者群体在广泛的地理范围内的特定繁殖地繁殖。由于饮食可能影响微生物组结构，我们从真核生物 18S rRNA 基因序列图谱中提取了饮食图谱。在广泛的地理采样的背景下，将细菌微生物组图谱与一系列不同的环境和生态措施结合起来进行研究。对超过 350 个粪便样本的细菌 16S 和真核生物 18S rRNA 基因测序的广泛地理采样与整合，确定了微生物组图谱与一系列地理和生态因素之间的关联。微生物组图谱因宿主物种、繁殖地身份、繁殖地之间的距离和饮食而不同。有趣的是，微生物组与宿主 DNA 比例（与总 18S rRNA 基因信号的关系）之间也存在关系，这可能反映了肠道通过时间。繁殖地身份与微生物组图谱的差异提供了最强的关联，表明当地因素在这些极地海鸟的微生物组结构中起着关键作用。这可能反映了通过粪便-口腔途径、雏鸟喂养或其他密切接触事件，微生物在当地的转移。其他因素，包括饮食和宿主物种，也与微生物组图谱的变化相关，在至少一些地点，个体之间的微生物组组成差异很大。鉴于与多种因素相关的企鹅微生物组的变化，在当地范围内微生物组关联可能会受到干扰，从而影响宿主的健康、生产力和免疫能力。微生物组是环境变化和其他压力源的更广泛背景下，变化条件的敏感指标。任何变化的影响都需要考虑在内。
