Our breeder buck that has been doing that since we brought him home last year... Sneezed the other day and slung slobber 6ft. We've given him everything under the sun and it never goes away. He eats good, acts fine otherwise and is growing great so although it bothers me I don't worry too much since I can't stop it. If it is an ailment he is living with it just fine. For all I know he could have a severe allergy because that's all he hasn't been treated for lol.