How fecal transplants may save Australia’s threatened koala population
While fecal transplants are being cautiously explored by mainstream scientists as novel treatments for everything from autism to inflammatory bowel disease, a new study led by University of Queensland researchers is suggesting the technique may help koalas in Australia adapt to new habitats.
"In 2013 the koala population reached very high densities, leading them to defoliate their preferred food tree species, manna gum," says Michaela Blyton, explaining the origin of the team's research. "This led to 70 per cent mortality due to starvation, which was very distressing."
The researchers observing the koalas noticed many of the starving animals did not feed on another species of eucalypt called messmate. While some koalas are known to exclusively consume messmate eucalypt leaves, it seemed the manna gum koalas were unable to transition to the different diet.
"This led me and colleague Dr Ben Moore at Western Sydney University to wonder if the microbes present in koalas' guts – their microbiomes – were limiting which species they could eat, and if we could allow them to expand their diet with fecal inoculations," says Blyton.
So, the researchers went and gathered fecal samples from messmate-eating koalas, concentrated the bacteria, and made fecal transplant capsules. The manna-gum-eating koalas were isolated in controlled conditions at a local ecology center, and fed the fecal capsules.
Over the next few weeks the animals' were studied and the results revealed distinct bacterial changes in the koala microbiomes after receiving the fecal transplants. The manna-gum-eating koalas now seemed much more willing to eat messmate.
Habitat loss is a growing problem for koalas in Australia. In the state of New South Wales for example, koala populations have declined by around 25 percent over the past 20 years. The National Parks Association of NSW recently suggested the extinction of koalas in the state in not impossible if habitats are not actively protected in the coming years.
Michaela Blyton views her team's research as a pathway to assist in maintaining koala populations, by helping the animals adapt to new diets.
"Koalas may naturally have trouble adapting to new diets when their usual food trees become over browsed or after being moved to a new location," says Blyton. "This study provides a proof of concept for the use of encapsulated fecal material to successfully introduce and establish new microbes in koalas' guts. In future, capsules could be used to adjust koalas' microbiomes prior to moving them to safer or more abundant environments, and as probiotics during and after antibiotic treatment."
The new research was published in the journal Animal Microbiome.
Source: University of Queensland