Dogs can get frequent yeast and bacterial infections in their ears. Dogs with heavier ear flaps (pinna) and more hair on and around the ears—cocker spaniels are classic for this problem—generally have more problems and infections. If your dog swims often it is best to try and make sure the outer part of the ear is dried afterward. Talk to your veterinarian about preventative wash with drying agents and how frequently you should use them to help keep infections from recurring.