Genetic calculator
Topic: color genetics
It is always a guess what any two rabbit genetic combinations will produce in the way of color. Sometimes the parent's genes are simple and sometimes (most often)they are not. If you are new at the breeding game, you might enjoy playing with probability calculators, which will show you potential color outcomes of any pair of rabbits mated together.

There's a new website in town, and Mamma Rabbit has such a calculator free on site. I just fooled with it for a bit and was entertained. The downside of any of these calculators (and they are included in most rabbit pedigree software programs, also) is that unless you have the parents' colors properly labeled, they are not even close. This ARBA (American Rabbit Breeder Association) rabbitry breeds show color rabbits, but some colors that pop out in litters are not showable. This is not an issue with fiber rabbits, but it does make the color names tough to settle on, when using an ARBA color list.

Color identification comes with experience, but there are some vital clues exhibited on day four of any angora's life that should not be missed. If you ever have a question about what color you have, feel free to contact me SENDING PICTURES of all sides (at least 6) of the kit and I'll send you MY guess. Then again, once the coat comes in fully, after 4-6 weeks, certain color modifications are evident (the color rings in an agouti coat and the ticking in a steel pattern, for example)and the original guess can be fine tuned.

At the end of the day, knowing the honest history of the colors in the parents, grandparents and great grandparents will be your best guide. Getting rabbits from people you trust will go a long way towards that end. Know thy breeder!

Chocolate and Tortoiseshell = ?
Topic: color genetics
I am always entertained by color genetics. I used to be consumed by predicting what color bunnies would be born if I paired certain rabbits. I learned a LOT by going after RED rabbits with French and English angoras for 8 years. [The red factor has been put on a back burner while I go after HEALTH in German crosses (not as easy as I hoped)].

At any rate, it struck me last night that Sydney and Neo have created an interesting litter.

Sydney is chocolate (and I while don't have a picture of her at the ready, here is an English angora I had years ago to show the color):

Neo is tortoiseshell:

and from their gene sharing, we got
4 black rabbits and 4 white rabbits:

This is a colorful business!

So here's how it works:
The dominant genes are ABCDE.
The recessive genes are abcde.
There are few moderately dominant and modifying genes, but in this case they do not come into play.

A complete discussion of how color shows itself in a black rabbit is here on the blog:
BareHare January 2004

Neo is aaB-CcD-ee.
Sydney is aabbCcD-E-.

I know what these parents are genetically because:
1. I have bred them before and seen what color bunnies they had. Neo has never had a chocolate bunny, but both his grandmothers were chocolate.
2. I have bred them before and know there are UNDERLYING genes in the "D" and "E" positions...therefore the white bunnies posses wild cards in that department!

In fact, I was SURE Neo had a chocolate gene. And he may have. That does not mean it will come out in any litter, even though the odds were fabulous that IF he had a chocolate gene, it would pair with Sydneys' and produce some chocolate bunnies.

They had black bunnies that are:
aaBbC-D-Ee
And white bunnies that are:
aab-cc--e-

Recessives can cruise along undetected for generations and then express themselves one fine day. But the nice thing about Sydneys' bunnies is that I KNOW each white and black bunny has a recessive "b" chocolate gene from Sydney, a recessive "a" self color gene from either parent, and a recessive "e" gene from Neo. The NEXT generation from this litter will produce those recessive expressions IF I pick the right parent.

Want to read more?
Links for color genetics in angora rabbits:
Island Gems
Kanien