My standard poodle, Whitney, (now at the Rainbow Bridge) had a "gassy" problem when we first got her and it was a little embarrassing at times, especially if company was over! It seems that the food the breeder had been giving her was the culprit and we, of course, had continued on with it not realizing that. Our vet also recommended a change in diet and told us to try Eukanuba. For Whitney, that was the end of the problem. I would suggest that if your vet can't find anything medically wrong with Herman (and I certainly hope it's not a medical problem) you may have to keep switching to another food until you find one that does the trick. Good luck!