I totally forgot about the Giardia thing. It is not fun and my mom's dog had it several times when he was a puppy. He would get liquid shooting stuff though and it was not pretty. But took him awhile to get back to normal after that...for treats I feed my grain sensative boy lamb treats and they work great. Come in big strips/squares but can be broken up into little bits. This is what I feed my guys
Merrick Pet Foods - Dog Treats
It seems pretty gentle on sensative stomachs. If I do that and the Orijen and cooked chicken as a treat then things stay pretty firm at my house. Thinking happy firm thoughts for you and your boy.