Judging by the record of food intake and the photo, I do not think he is not eating. I think he eats ok, then it just me.
I only give plain tin tuna or other tin fish.Code:I only have canned tuna for sandwiches at the moment. Is this ok to mix in with his kibble? And by plain yoghurt, I suppose it's not the yoghurt you find in supermarkets like Skii yoghurt?
Yogurt is also plain...I personally use Vaalia (as we eat it as well) but any brand will be fine. I try to avoid yogurt with cream mixed through such as some greek yogurt.
Some dogs are thin like some of us are thin (of course not us). As long as your dog is active I would not worry about eating too much.