We had really bad diarrhea probles with Wellness puppy food. We switched to Canidae suddenly (no gradual change) and he hasn't had any problems.
Wellness is an OK food but it is horribly overpriced. Have you tried Canidae? Innova? Solid Gold? Eagle Pack?
You know, that's quite funny...
Cause I had my 2 cats on Wellness and for a week and a half, they were really sick... One was trowing up and having diarrhea and the other one just diarrhea...
It took all this time before I finally realized it was the food that was making them sick.... I couldn't put together that this "great" food was making them sick... I was watching them to see if they were eating from the garbage or from their treat bags in the closet... They were very smart!! So I thought maybe...
So when I saw it wasen't any of this causing the problems, I went to my local pet store and both a bag of Royal Canin. I too gave it with no gradual change..... Just straight to RC, and you know what??
No more diarrhea or vomiting!! Everything just stop! Even if a gave them the new food straight out, they were better then ever!
So no, Wellness is not what is used to be.... Try something else... Like Timberwolf or Innova or Canidae.