[Kodak]

Please help, over the years my pups (7 yrs old and 4yrs old) have been on Eukanuba, Pro(something), Beneful, soft food, solid gold and I am now trying wellness. I mixed it so they can try to get use to it, now their stool changes or they just won't eat. The other foods, they wouldn't touch for days so i gave it away. I wound up having to give soft food to make them eat. What is highly recommended for yorkies, because I'm at the end of the food chain now. I also need a good treat recommendation that didn't change your dogs stool or make them stopped up. HELP!