Why choose their adult dog food? With hypoallergenic, easy to digest formulations and quality wholesome ingredients, Wainwright’s provides all the proteins, fatty acids, vitamins and minerals your adult dog needs.What does single source protein mean? Wainwright’s recipes are made with protein from a single source – just turkey, lamb or salmon, for example. For your dog, this means a tasty nutritious meal made with a protein they enjoy. For you, it means finding a food that agrees with them is so much simpler.