Doe surprised me....and questions.

My mixed breed doe kindled the other night and I found five kits in the nestbox. She obviously delivered a sixth kit outside the nestbox and on the cage wire between 10 and 24 hours later. I'm prone to think it was closer to the 24 hour side because the temperature was around 50 degrees F and the kit was still alive. I preliminarily warmed it and put it in the nest with the others.

If it isn't too elementary for you experienced folks, I have a few questions.
Is it common for a doe to take so long to kindle an entire litter?
Could this be an indication that she still might not be finished and may have an additional problem, such as another unborn fetus, that might threaten her welfare?

The dam is a Californian/Rex mix (she has typical Californian coloration) and the sire is a New Zealand Red. All the kits appear to have skin color that will produce totally red coats. Is there a genetic propensity for a particular breed's coloration to be dominant in such mixed breed pairings?

There are no elementary questions, really there are none. We all learn and relearn to better care for our animals. Please don't edit your questions. Ask away!

I've had a doe take all darn day, like 24 hours to deliver. From my experience it is not common for such a long labor but it occasionally happens.

Keep an eye on your doe, watching for signs of her being "off" such as loss of appetite, not caring for the kits, lethargic, more blood than usual. I do suppose you could take her temperature, but honestly I have no idea what it should be. A raised temp could mean an infection which would need a vet visit.

Sorry I'm no help with the genetic question. Maybe someone else will be able to help you.

"Normal" is for a doe to deliver all of the kits within a fairly short period; say, about half an hour. Occasionally one will take longer. People who have bred English Angoras have told me their breed is notorious for stringing kindling out over the course of two or three days. I have had numerous does deliver a few, and a few more hours later. The most extreme example I have had was a Jersey Wooly that kindled 3 one day, and 3 more about 3 days later, all from having been bred one time only.

You can palpate the doe to see if she still has kits inside her. If she does, the pressure may cause contractions, which could help. I have had does expel dead kits days after a litter is born. I have also handled a few does that had a dead kit mummified inside them, even had a couple that passed the mummy with a live litter. So though I can't swear that a dead kit inside her won't be a problem, it probably isn't cause for hitting the panic button, either.

The simple answer to your color question is no. There are a bunch of genes that are involved in coat color in rabbits, and it is the combined influence of all of them that produces the color you see. There are a couple of specific color genes that can basically overrule all of the others when a rabbit inherits a copy of them from both parents, but that is the gene, and it happens regardless of the breeds involved.

A lot of people get a little bit confused on what "dominant' means when it comes to genes. Dominant only refers to the expression of the gene, and has nothing to do with how frequently it gets inherited. If a rabbit has two different forms of a gene, one dominant, one recessive, each form has an equal chance of getting passed on. Each kit has an equal chance of getting either the dominant form or the recessive form. If a rabbit has two copies of either a dominant or a recessive gene, you know each of the offspring have to inherit that gene, because that's the only kind that parent has. But for you to see something that is the result of a recessive gene, you know that at least one parent is carrying that gene, and the other either has it or one even more recessive than it is.

Does usually kindle very quickly. Waiting an entire 24 hours is very unusual. As @animalmom said, keep a close watch on her. It is not neccessary to call a vet yet, but if she exhibits any of those signs, you may want to call or visit a vet.

One of mine on her first litter took almost a whole day to deliver. She had 2 close together, and the next 3 (which were stillborn) almost the next day. She ended up losing them all. Re-bred her within about a week and she had a healthy litter of 6 all within about an hour. My other two does delivered their entire litters within about an hour - 5 each.
I have no clue why she had them so strung out the first time, she was only bred once. But, it happened and after losing them all she had a nice big healthy litter a bit over a month later.
The one thing I noticed was that she wasn't in hard labor the entire time, which I think would be a lot more concerning.

I don't know if this is correct, but i read somewhere that first-time dams may lose the first litter they kindle. @Hopalong Causually , is your problem doe a first-time dam?

No, this is her second litter. She delivered eight at one sitting her first time. She was bred at only one engagement with the sire each time.
The kit born late was added to the others in the nest and has since fully recovered to the point where I can't discern which one it is. The doe appears to be completely normal also and keeping all the kits well fed.

Thanks everybody for the replies. Each time something unexpected happens, my first thought is to appeal to the experienced folks on the forum for their thoughts. If I can raise an issue that might help somebody in the future, so much the better.

Great!!!

That is an odd predicament. Most does get their "eventful litter" out of their system with the first mating. You should keep watching the doe and the kit. Marking the kits ear with a marker would help you be able to keep an eye on it.