Taurine is substance manufactured by most dogs from amino acids in the food.  (This is not the case with cats.) The reason why you see some taurine added to lamb formulas is because lamb is lower in the specific amino acids from which the taurine is independently manufactured by the dog's/puppy's body. However, in most cases, as long as there is not a predisposition to having an inability to manufacture this independently, they do not need it added to their diet.