Hi Luvlylady,
I am no expert but in the wild dogs would go days without eating and my friends St. Bernard seems to fast one or two days of the week - where she just turns her nose up at any food offered to her :shock: so it seems to be natural.
I guess like Gilly said in an earlier post "dogs do not starve themselves".
If she's not too thin then Bella's probably fine and just like the rest of us girlies - watching her figure :wink: