The Secret to Stopping Toxic Fungus: Moose Drool

Researchers find moose and reindeer saliva sports a substance that lets them eat grass deadly to other animals.

(Photo: Lucy Nicholson/Reuters)

Aug 8, 2014· 1 MIN READ
Todd Woody is TakePart's editorial director, environment.

Here’s another reason not to hunt moose: Scientists have discovered their saliva contains an enzyme that neutralizes a deadly fungus that grows on red fescue grass.

The fungus produces a toxin that would kill other animals, which quickly learn to avoid the grass. It’s a nifty self-defense mechanism for red fescue, but it’s no match for moose.

Or reindeer, for that matter. Their slobber also produces an enzyme that neutralizes the toxicity of red fescue, according to the study, which was published in the journal Biology Letter.

To get technical about it, moose and reindeer slobber “inhibits a grass-endophyte mutualism,” wrote the researchers, who are from the University of Cambridge in Cambridge, England, and York University in Toronto.

That means that over the eons red fescue and the fungus, called Epichloë festucae, have developed a I’ll-scratch-your-back-if-you-scratch-mine relationship. Red fescue provides a home for the fungus, which in return bumps off hungry herbivores that would devour its host.

Except it doesn’t work on moose and reindeer, which have evolved their own defenses.

It’s another example of the exceedingly complex web of life, of which much remains to be discovered.

“Large mammals play vital roles in maintaining everything from the vegetation of given ecosystems to the nutrients and carbon stocks that they hold,” Andrew Tanentzap, a plant scientist at the University of Cambridge and a coauthor of the study, said in an email. “Any changes to their numbers will have cascading effects on not just biodiversity but also ecosystem function.”

In this case, the scientists were curious about why moose could chow down on red fescue without getting sick, let alone dying. So they collected saliva samples from adult male moose and reindeer (after anesthetizing them, of course) at two Canadian zoos.

The researchers used distilled water as a control against the drool, applying both liquids to red fescue. The moose and reindeer saliva, they found, slowed the growth of the fungus and thus its toxicity.

In other words, moose spit is something like a palate cleanser that gets rid of that nasty toxic taste of fungus before the main course of red fescue.

They may be big, but moose aren’t dumb.