Treating Koalas for Chlamydia Alters Gut Microbes

Koalas are one of Australia’s iconic animals, but they have been hard hit by an epidemic of Chlamydia infections contributing to a steep decline in numbers. Sick koalas brought to wildlife hospitals may be treated with antibiotics to clear up the chlamydia, but the antibiotics themselves can have severe side effects in the animals.

Koala

Koalas feed almost exclusively on eucalyptus leaves. They depend on gut bacteria to make the leaves digestible. (Photo via Tourism Australia)

A new study led by Katherine Dahlhausen, a graduate student at the UC Davis Genome Center, published in the journal PeerJ, shows that those antibiotics may be changing the balance of gut microbes thought to allow koalas to digest eucalyptus leaves.