I have lost the last two litters--first time does. One ate the babies....after leaving the poor things on the wire. The other one did fine for 3 days, then I think she got scared--neighborhood dogs--and they froze. I grew up raising rabbits in Pennsylvania, for pete's sake! Those bunnies never had any trouble with winter babies. What is with these darn rabbits? It is breaking my kids hearts. Even if we're going to eat them, they (and I) don't want to watch the babies die so young.......
With the exception of 1 doe, I have had tremendous luck breeding 'bad' mommies directly after losing the litter. If you breed them as soon as it happens, that normally gets them on track. Sorry for your losses. Our children may feel the same when something happens, but they know and are reminded almost daily, none of the animals are pets, they are food. Pets, on the other hand, are a different story, and the occasional pity case that gets spared.
If I read your post correctly I think that the problem is more with first time does than the winter weather. If kits are delivered in a nest properly made by the doe with adequate hair in it and the doe feeds the kits IMHO the kits will do fine in most winter weather if they are dry and out of drafts. I would advise that you rebreed the does and see if they aren't better mothers the second time around. Good luck.
