Variation in koala microbiomes within and between individuals: eﬀect of body region and captivity status
Niccoló Alfano1, Alexandre Courtiol1, Hanna Vielgrader2, Peter Timms3, Alfred L. Roca4 & Alex D. Greenwood1
1Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
2Tiergarten Schönbrunn, Vienna, Austria
3University of the Sunshine Coast, Sippy Downs, Queensland, Australia
4Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
Correspondence and requests for materials should be addressed to A.D.G. (email: )
Metagenomic analysis of 16S ribosomal RNA has been used to profile microbial communities at high resolution, and to examine their association with host diet or diseases. We examined the oral and gut microbiome composition of two captive koalas to determine whether bacterial communities are unusual in this species, given that their diet consists almost exclusively of Eucalyptus leaves. Despite a highly specialized diet, koala oral and gut microbiomes were similar in composition to the microbiomes from the same body regions of other mammals. Rectal swabs contained all of the diversity present in faecal samples, along with additional taxa, suggesting that faecal bacterial communities may merely subsample the gut bacterial diversity. Furthermore, the faecal microbiomes of the captive koalas were similar to those reported for wild koalas, suggesting that captivity may not compromise koala microbial health. Since koalas frequently suﬀer from ocular diseases caused by Chlamydia infection, we also examined the eye microbiome composition of two captive koalas, establishing the healthy baseline for this body part. The eye microbial community was very diverse, similar to other mammalian ocular microbiomes but with an unusually high representation of bacteria from the family Phyllobacteriaceae.