Hello,
My Angel started with her Allergy to chicken as a puppy and it was explosive diarrhea, so be careful. I never in a million years thought a dog would have an allergy to chicken but turns out a lot of dogs do and they also have allergies to the grains too. Once I took her off the chicken and grains, unfortunately had no choice but to use the I.D diet by science diet to settle her GI upset for 10 days. Once that was settled, I used a grain free puppy food, and she was much better. In my girls case it was the chicken and grains causing her explosive diarrhea.
Angel did have some loose stool during the transition but not diarrhea.
Best of luck to you.
