My 11.5yr old Illy has definitely lost weight very gradually over the last year or two. I give her science selective senior pellets (probably more than others on the forum would) and lots of treats to keep the weight on. I suspect it's just a matter of getting older, but your vet can always do blood tests if you're worried. Illy has had the full works of tests, including a CT scan, so we're confident we know what's going on and that it's a combination of age and heart troubles.
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