No, that would be dangerous! Mice have a very fast metabolism, so they need continuous intakes of new feed.
Can I give my mice snacks?
Of course, but ideally give them small snacks alongside their main feed. Witte Molen has a broad range of delicious natural treats for rodents. You can also give them an additional small piece of vegetable or fruit once in a while, but don’t give them too much at once as they’re only tiny!