Aside from an accumulation of dirt, a persistent and unpleasant doggie odor could be caused by many factors including dental disease, ear infections, or oily skin. A closer look at your dog may help you find the problem. Look in your dog’s mouth. Are the teeth discolored? Do you sniff more than the usual “doggie breath?” If so, a visit to the veterinarian for a dental checkup and treatment is in order. Your veterinarian can also explain how you can clean your dog’s teeth to help protect against future dental disease.

Ear infections are frequently the cause of an offensive odor, especially among long-eared and floppy-eared dogs. The inside of the ear becomes moist and hot, providing the perfect environment for infections. Take a close look inside your dog’s ears. Is the skin red and sore? Does the dog cry out in pain as you try to examine the ears? Does the ear canal have a bad odor? Any of these may be warning signs of an ear infection which should be treated by a veterinarian.

Do you feel a slight greasiness on your hands after you pet your dog? This may be an indication of seborrhea, a common skin disorder in dogs. These dogs have excess production of sebum, a normal product of the skin glands. The result can be flaky dandruff or an oily, waxy feel to the hair coat and a strong odor. Seborrhea may also dispose a dog to skin and ear infections. Frequent bathing with a medicated shampoo recommended by your veterinarian can help prevent much of the odor.

One other possibility for your dog’s odor may be its rear end. Infection or improper emptying of the anal glands can cause odor and discomfort to the dog and a trip to the veterinarian is in order. Longhaired dogs sometimes have a soiled rear from defecating. Without daily brushing, the rear can become matted and smelly. Monthly clipping around the rear end helps, as do daily brushing and grooming. Once you have investigated the cause of your dog’s odor you can begin to help control it. Enlist the aid of your veterinarian in identifying the problem, treating it, if necessary, and controlling it in the future. Never forget the importance of grooming on a regular basis. It is essential to keep a haircoat healthy by removing scale, dirt and dead hair; distributing the natural oils throughout the coat and preventing mats and tangles in long hair.

Source - Yahoo Pets

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"Responsible Dog Ownership - Essential Tips for Every Dog Lover"