A/at/a Genetics and Otter vs Self-Color Kit Identification

I have been studying rabbit genetics of all things lately.  Mostly because a friend of mine has started to bounce around the idea of creating a new variety of New Zealand (NZ) Rabbit: Chocolate.  Then Clarissa decided she wanted to raise, breed and show mini rex and that added a whole new spin to the need to understand genetics since there are so many more colors and varieties of mini rex than their are NZ rabbits.  And their genetics are pretty simple breed white to white, red to red or broken red, black to black or broken black, and blue to blue or broken blue and never the colors shall mix.  But with mini rex colors and genetics are a completely different story.

Mini Rex come in the following colors:

• Black
• Blue
• Tri-color: Black/Orange, Chocolate/Orange, Blue/Fawn, Lilac/Fawn
• Castor
• Chinchilla
• Chocolate
• Himalayan: Black, Blue
• Lilac
• Lynx
• Opal
• Otter: Black, Blue, Chocolate, Lilac
• Red
• Sable
• Sable Point
• Seal
• Silver Marten: Black, Blue, Chocolate, Lilac
• Smoke Pearl
• Tortoise (Tort)
• White: Blue Eyed White (BEW) & Red Eyed White (REW)
• "Broken" followed by the color comprising the broken (for example: Broken Black)

It also seems that it would be worth mentioning that there are other colors that are possible such as harlequin & magpie (I mention these because you need them to breed tri-color but they are not recognized varieties by the American Rabbit Breeders Association (ARBA) and not showable at this time.)

As you can see it is quite a list and in order to really be successful at breeding quality animals it is going to take some understanding of genetics and how they work.  Since the first gene I studied was black verses chocolate color (Bb).  You can read about that here.  The Aa^ta gene seemed like the next logical choice especially when I stumbled upon a photo in one of my Facebook groups where they showed comparisons of types of this gene for kit identification and comparison.  Genes come in pairs and are listed in order of dominance so I am going to tell you about each gene from most dominant to least dominant.

A = gives you the look of a wild rabbit, with dark hairs called "ticking" mixed throughout their lighter colored body coat.  They will also have tan, fawn or white around their eye circles, in a triangle at the nape of their neck as well as on their feet, legs and inside their ears.  They will also have a white belly.  A gene is also called Agouti Pattern and mini rex varieties in this group are Castor, Chinchilla, Lynx, Opal and Red.

a^t = gives you self colored fur with no ring color or band in the middle of their fur and they also have no ticking.  They are solid colored on the top and body of their fur with tan, fawn or white around their eye circles, in a triangle at the nape of their neck as well as on their feet, legs and inside their ears.  They will also have a white belly.  a^t gene is also called Tan Pattern and mini rex varieties in this group are Otter and Silver Marten.

a = gives you solid colored fur that lacks rings or bands and is the same color throughout the fur.  a gene is called the Self-Color and mini rex varieties in this group are black, blue, chocolate and lilac.  This group also includes some genetically self rabbits with shading, but it is important to remember that a genetically self-colored rabbit will never have the agouti or tan pattern markings.  The shaded varieties of mini rex are seal, sable, sable point, smoke pearl, and tort.

What does this all mean when it comes to breeding rabbits?  Well depending upon the genetics of the breeding pair of rabbits you are going to have 4 possible combinations.  Lets say our example buck is AA and our example doe Aa.  I like to make a little table to help me understand the possible outcomes.  I take the bucks genes in blue and the does gene in pink and then I add each pair combination together.

A a A AA Aa A AA Aa

The results are kits that can be either AA or Aa. Because the A is the most dominant all the offspring will look like the A agouti pattern rabbits.  The fun part in all of this is definitely the baby bunnies.  And learning how to identify the kits correctly can be a real challenge.  Sometimes a picture is worth a thousand words and this one does a fantastic job of showing you the differences between not only the Bb gene but also the a^ta gene.  I hope you find it as helpful as I did.

Photo provided by WindFall Farms

One of the comments that Windfall Farms made on the Facebook group post about identifying kits and how do you get so you can do it accurately everytime was this"Practice is the short answer. As kits self-colored (black, chocolate, blue and lilac) will be all one color. Otter (black otter, chocolate otter, blue otter, lilac otter) and Agouti (Castor, Amber, Opal and Lynx) will have white bellies, inner ears and markings at the back of the neck, nostrils and around the eyes."

A big thank you goes to WindFall Farms who was willing to share her picture of kit identification with me so I can share it with all of you.  You can find their Farm page on Facebook: WindFall Farms.