So I'm confused why that doe and the original buck never had REWs, because they would both have to carry it, right? Just luck of the draw in 13 kits over 3 litters?
Yes, they both carry it as shown by the breeding. Just by chance they didn't produce it when bred together.
Recessives are like that sometimes, you can't really prove that rabbits don't carry _____ recessive gene if they don't produce it, just the likelihood of them having it reduces. "Recessives are forever" is something you may hear, lol.
Like I just bred my gold tipped steel with my red and she kindled this morning. Her first litter, just 5 little squeakers, all are full color C. It's not unlikely that she is CC, as both of her parents were full color rabbits and the sire to this litter was Cc so there is indeed space her recessive gene on the c-locus to present itself but if it is there it just didn't this time. So while I do have an inkling she's probably CC, I would be foolish to write that in her pedigree yet. If she constantly only produces full color rabbits for the next 5 or so litters then I'll assume it to be the case. But it's not PROVEN and there is still a chance suddenly she'll kindle a chin, or himi, or REW kit and I'll go
"Ya gotta be kitten me."
That's how it worked with the chocolate gene for me. I would have bet my rabbitry that I didn't have chocolate in my herd and then one day the stars aligned and.... Chocolate chinchilla, lilac chinchilla, chocolate ermine and lilac self popped up in the same litter.
"WHAT THE HECK!?" It was a happy surprise during a depressing few months.
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Long story short, I do believe you have self chins. The brown eyed blacks could also be self chins but you wouldn't know unless you test bred them to say, an agouti based REW, and got a litter of REWs and Chins.
Pictured is an adult self chinchilla I had in the past, and you can do a search on FB for "NotAllBlueEyesAreVienna" and pull up a bunch of blue eyed chin based rabbits.