Is he drinking? Are his poos okay - as in firm, normal? Is he lethargic or anything? Any vomiting?
I mean, it could be bc of what Deb said - if he is not altered. But if he's really lost his appetite, that's concerning - bc dogs don't do that unless they're sick, usually (or, what Deb said).
Have you switched foods on him or anything? Do you want to try another one to see if it's just due to boredom? Or, you could add some canned to his kibble, what about that?
