Some animals have an amazing capacity for producing slobber, or saliva — moose and reindeer for example.
You might wonder why. After all, moose are just a bigger version of a cow, munching their way through their forest-wetland habitat.
Among the variety of leaves, twigs, and tree browse and aquatic plants that are fed upon, moose also favor a diet of red fescue. But red fescue grasses have fought back against being eaten with a special kind of anti-herbivore defense: symbiotic fungi that live within the lower parts of the grass and produce poisonous alkaloid compounds. Ingestion of too much red fescue could kill even a large herbivore like a moose.
In a counter strategy, to combat this potentially toxic encounter, moose secrete a host of anti-fungal compounds in their saliva, some of which have long lasting properties that diminish future production of alkaloids in patches of red fescue on which they have fed. Reapplication of moose drool on the grass in their territory keeps the fungal toxins at a manageable level.
But it takes lots of saliva to make a moose’s favorite feeding areas palatable — hence the copious drooling for which they are noted.
How much drool? Well, a cow might secrete 10-45 gallons of saliva per day depending on the dryness of the forage. A conservative estimate of the quantity of moose drool produced might be 50-60 gallons per day to digest the 50-60 pounds of forage a moose must eat daily to stay healthy.
No wonder they stay near water, both to cool them off and to provide the basis for their continual drool.