Hi Atlas,
If he is still not gaining weight, I would increase his food even though you said calories are there.
The soft poo at the end and frequency could be due do not enough gut bacteria especially since the food he is eating does not contain probiotics. I occasionally have that issue with my grain intolerant girl. I used to give the girls pet probiotics, but I have found that kefir seems to populate the gut faster and better than everything I have tried in the past. Also, when you consider the price of pet probiotics, kefir is a lot cheaper. I use Lifeway Plain Kefir that I buy at my regular grocery store.
I would personally try a few more days to get the poo less frequent and more consistent firmness before starting the Nature’s Domain. (Since he is a large breed I do think the transition needs to be done fairly soon to meet his growing needs.) If you want to try kefir, start with 1 tablespoon once a day and see what happens, and if necessary twice a day. I give 30 or 40 minutes before a meal–if he gets runny during the transition, mix the kefir with his food or give to him right before he eats.
When you used to leave his food out, did you try to touch or pet him while he was eating?
