Duck is a great protein source with many nutritional benefits for your pet, including a well-balanced array of amino acids. Duck also contains generous amounts of iron, phosphorus, zinc, copper, thiamin, riboflavin, niacin, Vitamin B6, and Vitamin B12.  Both zinc and selenium are antioxidants that help to boost the immune system. Selenium also helps to maintain normal thyroid function. Another nutritional benefit to duck is its content of omega-3 fatty acids, which help to provide your pet with healthy skin and coat.  Many pet owners with dogs that have food allergies prefer foods containing duck, due to the fact that duck is probably one of the best protein sources for dogs that suffer from allergies to other meats.