Does Royal Canine contain any artificial additives (E-numbers, preservatives)?
Does it contain (wheat) gluten (some dogs are allergic to gluten; our pyrenees is one of them)?
What is the protein level (you should not really be much over 20% for a pyr older than about 5 months)?
Some dogs can also be allergic to chicken, rice, dairy products, egg, soya...
Our pyrenees is on
CSJ CP18. and he is doing great on it. It is gluten free and free of artificial additives.
Other good foods are Burns, James Wellbeloved, Nutro... to name just a few.
It is just a suggestion... :)