Faecal inoculations alter the gastrointestinal microbiome and allow dietary expansion in a wild specialist herbivore, the koala

Background: Differences between individuals in their gastrointestinal microbiomes can lead to variation in their ability to persist on particular diets. Koalas are dietary specialists, feeding almost exclusively on Eucalyptus foliage but many individuals will not feed on particular Eucalyptus species that are adequate food for other individuals, even when facing starvation. We undertook a faecal inoculation experiment to test whether a koala’s gastrointestinal (GI) microbiome influences their diet. Wild-caught koalas that initially fed on the preferred manna gum (Eucalyptus viminalis) were brought into captivity and orally inoculated with encapsulated material derived from faeces from koalas feeding on either the less preferred messmate (E. obliqua; treatment) or manna gum (control). Results: The gastrointestinal microbiomes of wild koalas feeding primarily on manna gum were distinct from those feeding primarily on messmate. We found that the gastrointestinal microbiomes of koalas were ...

背景：个体间胃肠道微生物组（gastrointestinal microbiome, GI microbiome）的差异可导致其在特定饮食上的生存能力产生分化。考拉为饮食特化物种，几乎仅以桉树叶为食，但诸多个体不会取食对其他考拉而言适宜的特定桉树种，即便面临饥饿亦如此。本研究开展粪便接种实验，以探究考拉的胃肠道微生物组是否会影响其饮食选择。研究人员将最初偏好取食甘露桉（Eucalyptus viminalis）的野生捕获考拉转入圈养环境，分别口服接种由取食非偏好桉木桉（E. obliqua，处理组）或甘露桉（对照组）的考拉粪便制备的胶囊化材料。
结果：主要取食甘露桉的野生考拉，其胃肠道微生物组与主要取食桉木桉的个体存在显著差异。研究发现，考拉的胃肠道微生物组……