You guys are probably sick of this question but here it goes..

Is it really necessary to eventually feed a garter mice, I mean, can you feed him or her on a diet of fish and worms his/her whole life and be assured that she/he will be as healthy as a mice fed garter? And do mice have more nutritional values than fish? Is it possible that a mice fed garter might live longer with a more nutritionally balanced meal or the other way a round?

cheers..