A. There's a good chance he has parasites. Even if your vet dewormed him he could still have other parasites that aren't affected by the routine dewormers we typically use. Take him in for an exam, along with a sample of the feces for your vet to analyze. Hopefully this is something fairly routine - chances are pretty good that it is since he still feels well, but get him in so that he can be treated and get well soon.
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