I know this dog food is suppose to be really good for animals, and it's probably just my dogs weak stomach or something. But I have a 1 year old bull mastiff. And we started her out on Blue Buffalos Large breed puppy food. We had her in and out of the vet for about a month because her stool was soft. It was not diarreha, just soft. Finally, we switched her food to Royal Canine and now she doesn't have any problems.