what causes dogs to have ear infections
Food (or environmental) allergies are especially likely to be implicated in ear problems when both ears are involved. An excess of grain and / or sugar in the diet is one of the most common causes of ear infections in dogs. The sugar actually feeds the yeast which lives naturally in the body and causes a yeast overgrowth, which results in the dark, yeasty-smelling buildup that can occur inside the ears.
Certain breeds, such as Labradors and others with long, hanging ears, are more at risk of getting ear infections. Other dogs, like poodles, have a lot of hair in their ear canals that puts them at risk for infections when wax and dirt become trapped within the hair. Any breed of dog that has a type of allergic skin disease can suffer with chronic ear infections as well.