YAY, so happy to hear that he's feeling better and eating!!
Jumping up and down!!!!!
Maybe you could alternate the carbs with something like barley and oatmeal, too, depending how he feels and how his poops turn out. Barley congee (I filtered out the grain bits but pushed the "goods" through strainer) worked super well for MP this time around.
My rehab vet who is super knowledgeable (and very conservative about usage, which I really like!) about pain meds doesn't believe Tramadol alone (as opposed to being used as an adjunct for NSAIDS) is very effective for most dogs, and prefers to use Gabapentin for meds in that class of drugs. You could see if that may work for Roscoe better, should he need a different one at some point. She told me this when my reg vet gave us Tramadol for MP's leg gash that one time, and also when we talked about pain management for her owie shoulder.