I posted the same question in the Boxer Ring on 5/12. I also have another post under feeding which has to do with type of food. Check out all the helpful replies I got.
Otto was on Nutro large breed puppy until around 1 year and then we switched to Nutro large breed adult. We started to make the switch and he didn't seem to tolerate it (see my post)so we immediately stopped and went back to his puppy food for a few weeks.
We just started to introduce Nutro Lamb and Rice as recommended by another member. So far so good.
Cheryl & Otto