Natural Balance Limited Ingredient Diets Grain Free Duck & Potato Recipe Natural Balance Limited Ingredient Diets Duck & Potato Treats is a proven formula for dogs with allergies, based on a unique blend of a premium protein and carbohydrate not commonly found in dog foods. Contains no wheat, barley, rice or corn. Available in a 8 oz. size with treats made especially for small breeds and in 14 oz. and 28 oz. sizes for all breeds, from puppies to adults.