Genetics questions

[Blaze_Amita]

Okay background first:

Original New Zealand Reds: Trisha and half sister(same dad, different mothers- no papers but saw parents) Rosie1 and Aragorn(said to be purebred, but no papers)

Now We have Rosie2 and Ruby- out of Rosie 1 and Aragorn

Stryder(buck), Trina and Trixie out of Trisha and Aragorn. All the parents have moved to other breeding homes(4H raisers)

Bred Trina to her littermate(by mistake, I forgot to seperate them early enough) and the kits are perfectly normal. Trixie to her father- kits are perfectly normal. Ruby hasnt' been bred yet but Rosie2 bred back to her father and she has 2 kits- one normal NZR fur and the other has rex fur.

What on earth? I am assuming right now that it came down out of Aragorn, as I never saw his parents I could only go by what I was told. I've got several 4Her's that want to raise them(as the reds are very pretty) but I am hesitant to sell any of mine as NZR's-even after 2-3 generations if I have the possibilities of them tossing the rex coats- could there be some red rex behind my buck-seeing as he's the one I didn't see the parents to?

I hope this makes sense to some genentic guru's.

 

[funnybunnymummy]

I am in no a way a genetic expert, but I am fascinated by genetics and have done some reading up on the rex fur gene. As I understand it, the rex fur gene is recessive and both parents need to have it to produce offspring with rex fur. Breed a rabbit with one rex gene to a rabbit with no rex genes and you'll never see rex fur in the offspring, even though 1 in 4 will be carrying the gene.

So it sounds like Aragorn has one rex fur gene and Rosie2 has one rex fur gene (which she would've got from her father), hence the kit with rex fur. Odds are Trixie doesn't have the gene (instead she'd have got 1 regular fur gene from each of her parents) since breeding her back to her father produced no rex kits. And either Trina or Stryder both don't carry the gene or one does and the other doesn't.

The most obvious way to determine which of your rabbits carries the rex gene would be to get a rex buck and breed him to your does. The buck will consistently provide 1 rex gene. Your does will provide either a regular fur gene or the rex gene, depending on what they're carrying. So if any rex kits show up, your doe has the rex gene. No rexes, I think you can safely say she doesn't.

Hope that helps!

Rue

 

[CCWelch]

If there is any broken in the New Zealand background it is usually done by mixing in a broken rex to get the broken pattern. Sometimes it crops up most often during line or in breeding.

We see something almost the same in our Satins, if a New Zealand has been added for size then occasionally we will get "normal' furred young but only if we are line breeding.