It probably is the food. Some foods just don't agree with some dogs. I feed Molli and Sammy Nutro Ultra, and they do well on it. It just depends on the dog. Maybe try another food if she is still having problems? Or a vet appointment may be in order.

Don't feel bad about fasting her. I've fasted for a couple weeks when I got my tonsils (sp?) out and I didn't mind because I wasn't feeling well. 24 hours won't effect her at all.

Hope she feels better!