First off, It is NOT GOOD to shave a short haired dog. That hair call an undercoat is to help the stay cool and warm.
Second: Bath your dog once a week and get a slicker brush. Brush you dog everyday.
Third: Environment and diet changes will cause shedding or what is called (blowing coat). My two dogs, Belgian Malinois (they looking my German Shepards) blow coat twice a year and shed regularly.
Forth: Yea, it sucks but if your going to get a large dog,and don't like the shedding, then you should have gotten one with hair not fur.
DON'T SHAVE YOUR DOG. even if you shave it the fur is still there it is just smaller. So you will still be the shedding effect, just smaller pieces. I have friends that have Aussie's and Goldens. They shave them, but only to a puppy cut. Again, It is bad to shave a short haired dog. They are made that way for a reason.
Why you do I think I know so much........ Well I have shown dogs for 12 years.