I feed BB food/treats and actually that is the food/treats I went back to after trying The Honest Kitchen, Acana and Nature's Variety. It is the only thing that doesn't give her major diaherra... I do also have problems with Wellness treats as well. I have to be so careful with Taycie, even if the makeup of the food or treat seems somewhat similar to BB.
I don't know why, but it works for us and I am sorry you and little Ian have had issues with it. I guess it goes to show what works for some does doesn't work for all
I do know they are ethoxyquin free. I was worried about this as well as I did not see it on the food but it is stated on the website
Blue Buffalo - Our Nutritious Dog Food and Cat Food Philosophy
If you scroll down to the bottom of the link it states what is NOT in Blue.. (it says):
Preservatives like BHA, BHT, ethoxyquin, propylene glycol provide no nutritional value and have been associated with possible toxic side effects. Some pet food brands resort to artificial colors and flavors in an attempt to make food look and taste better. We don’t.
I hope this helps! I am sorry I know how frusting this can be!