My 11 week golden retriever, Scotch, has been eating Nulo Freestyle Puppy for the past couple weeks, and it doesn't seem to agree with his tummy. Initially he was on the turkey formula and we switched to salmon to see if that would help, but it doesn't seem much better. Anyone have any recommendations? We have been giving him pumpkin, which does help, but obviously is not a long term solution. Would love any advice you guys have!