We do have Chloe in training, as a matter of fact, she trains with Mitch Fletcher, who was on animal planet for some time, been training for over 2 months now. On our first visit he explained the different reasons for a dog to have aggression and one of them was if the dog was in some kind of pain...tooth, joints, stomach, etc. Also, some dogs have allergies to corn, it's hard for them to digest. The studies I looked at said that foods that are easier to digest can make all the difference in the animal's disposition. I guess it would compare to people...some foods give us indigestion, gas, upset stomach, constipation, etc. I figured it was worth a try. Our dogs are both on Purina One, we are gradually adding Nutro Ultra for small breed dogs. It has complex carbohydrates, no corn and a lot of natural ingredients...I figured this was worth a shot. I love my little dog, but her unpredictable personality, snapping and aggression towards our other dog, being kenneled, and the non-stop barking is working on everyone in the family. We recently tried the ultra sonic egg to control barking....she barked worse...non-stop and was very angry...while our other dog (mini schnauzer) coward in the corner...