As its name shows Royal Canin Giant Puppy is suitable for all the Giant Dog Breeds Like Great Dane,Bull Mastiff,English Mastiff,St. Bernard,Neapolitan Mastiff etc.
In generally, the Rottweiler breed is including in the giant breed due to its inheriting with big and potential body shape/size. Having seen their potential body shape, the animal experts have chosen them as giant breed and in providing such breed of dog with the easiest digestible along with best nutritional dog foods would more beneficial. You can feed your Rottweiler the Royal Canin Giant Starter, 4kg, Pedigree puppy Large Breed 10KG, Pedigree Puppy Dog Food Chicken Milk 3 KG pack etc.
The feeding guidelines have mentioned on the pouch as in print message based otherwise you can take the advice of a veterinarian expert/physician.
It is so simple, just keep them tightly inside a container which could not be damaged/effected due to the moisturizing weather, it means try your best not to allow it by keeping in an open environment.