I like to transition over one or two weeks, not just because the transition to a different formula can cause some loose stools, I think the pup takes to the new food better if it is introduced slowly.....I have never just "sprung" anything new onto my dogs or kids....kind of just always "worked anything new" into the already established situation"!
Kind of seems like it gives them time to get used to a couple of new pieces of whatever, placed in what they have already been eating. |