Diet Change
The coat health of a dog directly relates to his internal health. If his coat is dull and matted, despite grooming and bathing, perhaps he's not getting the proper nutrition he needs. The key to a beautiful coat and healthy dog is a balanced diet. High quality pet foods attempt to give your dog all the vitamins and nutrients he needs.
That being said, a proper canine diet should consist of between 21% to 25% protein. An active dog should receive about 25% protein. Dog foods should also contain vegetable material, and not just corn, wheat and flour products. If a meat like lamb, beef, or chicken is not the first ingredient in your dog's food, you should switch brands. Remember to be patient; it can take up to three months for there to be any noticeable difference in your dog's fur.
Avoid Corn
A common cause of a dull coat is food allergies, and an allergy to corn is very common in dogs. Corn also has very little nutritional value for dogs. So replace corn-based treats and biscuits with protein or fruit and vegetable-based ones.
Olive Oil
By adding a teaspoon of olive oil to one of your dog's meals every day will not only make his fur glossy, but also strengthen his nails.
Essential Fatty Acids
Essential Fatty Acids are vital for a healthy coat. These are the good kind of fats, known as Omega 3 and Omega 6. They can be found in fish oil, sunflower oil, canola oil, olive oil and flaxseed oil. Just add a teaspoon to one meal a day. A difference in the coat can be seen within a week or two.
Raw Food Diet
Biologically Appropriate Raw Food for dogs is sometimes recommended by vets and breeders. This food consists of raw vegetables, fruits, meats and bones. Some people claim they see a significant difference. It is best you talk to your vet about this option before you try it.