storm_onj:
Your dog's genes will dicatate how big he'll get. If you overfeed your puppy, he'll get bigger all right--he'll get FAT. This is one of the worst things to do to a growing puppy because the extra weight can cause problems for his growing skeleton. A leaner puppy is by far & away a healthier puppy than a fat puppy.
There are no supplements you can feed him that will make him get any bigger.
Male Rottie are mature when they're about 3 yo.
I can't understand people's obsession with the size of their Rotties--bigger isn't better.
Please, read both the AKC (
http://www.akc.org/breeds/recbreeds/rotty.cfm) and the European (
http://www.USRCWEB.org/fcistand.html?) standards. Both say "The ideal Rottweiler is a medium large, robust and powerful dog, black with clearly defined rust markings. His compact and substantial build denotes great strength, agility and endurance."
Also, the food you're feeding him--both the dry & canned foods--aren't very good. In another post you listed foods availabe in your country and there's at least one premium food that would be *much* better for you to feed.