Most of the strays we’ve taken in have gone from starving to fat in the first year, but then they lose the excess weight during the second and third years when they’re assured of a consistent food source.
Miss Hissy Slashy is the exception, and we’re working now to get her to trim down, but with a cat, it must be done slowly, or her liver might be damaged. It’s a delicate process, but we’re pretty sure that she will lose the excess eventually.
I made a “toy” for her. I cut a hole in the side of a small, empty plastic vitamin bottle. Every morning I fill it up with cat kibble, less than a half cup. It took me a few days of gently pushing the bottle with her paws for her to get the hang of it, but now she knows how to get the kibble on her own, and she gets some exercise playing with her “toy.”
Our cat Shadow was also looking pretty tubby, but it turned out that she was just bloated from having some sort of feline IBS. Lysine and feline probiotics added to her diet have cured her (and her stinky business if you know what I mean).
My Deimos is something of a big boy, but the vet doesn’t have a problem with it. If he didn’t like to sleep on my chest I wouldn’t worry.