I typically don't mess with the bellies unless I notice mats. My rabbits are pretty good about keeping their bellies well taken care of, and when you start adding to your population, it takes more time to groom. So long as there's no mats, I figure they're good to go. None of the rabbits I brought in like their bellies messed with either.
That being said, I do try to train my kits to lay on their back and let me mess with their bellies no problem, but it's very hard to get an older rabbit to be comfortable with that no matter how much they like attention otherwise. If your a prey animal that's only real self preservation technique is to run, then when your feet aren't on the ground you won't be very likely to feel safe until they are again. It's just something we learn to deal with.
However, as a note of caution, rabbits are strong enough to break their own backs by thrashing on their backs like that, so if you do have to flip her see if you can wrap her up somehow that it won't inhibit you from working on her, but so she can't wiggle. Some of mine will even calm down if cradled tightly like you would with a human baby, so you could try that too.<br /><br />__________ Sat Nov 09, 2013 7:56 am __________<br /><br />Oh, and when I do deal with mats I typically pluck them out quickly while I hold the rabbit with one arm. All of my rabbits do well held in what they call the rag doll position, where you hold them up against your side or front with one arm under their elbows basically, and the rest of the rabbit hanging against your body. It frees up a hand to pluck the mats while they are comfortably hanging stretched out where I can see their bellies. They don't mind it in the least once their used to it, but it usually takes them a couple times to realize they're not falling or getting dropped.