As stated a weekly bath is fine, its not frequency that will cause issues, it what you use to bath them with. Human products are a no go, you wouldn't wash your hair with dog shampoo now would you? Their ears can stink even if they dont have an infection. If your dog has floppy ears they need to be addressed at bath times. There are many products out there that will dissolve the ear wax for easy removal (dont be jamming qtips in your dogs ears) to be followed by a drying agent and will leave their ears nice and dry and odor free. Diet can also play a major role. If you are feeding your dog anything that you bought out of a grocery store then change their diet. There isnt a single grocery store brand that is good for your dog, NOT ONE! Most have a main ingrdient of corn and corn gluten. Dogs cannot digest corn and nothing on the face of the planet can digest corn gluten (the left over outer shell after every bit of nutritional value has been removed) Your dog foods first few listed ingredients should be meat. Like chicken, chicken meal etc. Not byproducts which equates to whatever is left that the FDA wont allow them to use for human consumption like ground up feet. Wheat is also not good for dogs and has been linked to allergy promotion in dogs (not just an allergic reaction to wheat but increased reactions to other things especially their skin and coat). Most pet stores have a premium aisle with holistic foods but you will find NONE in the grocery store! Here is a link to a non biased website that provides nutritional information on dog foods with a star rating system. 1 being the lowest and not at all recommended (this is where you will find grocery store brands) and 5 being the highest. Anything 4 stars or more will be better for your dog. He will thank you for it! Also be aware that you should never abruptly change your dogs diet. Start with 1/4 of the new mixed with 3/4 of the old and work your way over to 100% of the new over a 2 week period. I did a lot of research on this becasue my dogs skin was drying out, he was itching a lot and shed more than he should. I was bathing once per week and using premium shampoo. In the end it was the dog food. I now feed him Blue Buffalo Chicken with brown rice for large breeds which is readily available at Pet Smart.