B Genes

The B locus controls whether a rabbit is black based (B) or chocolate based (b).

Black (B_)

A Black Mini Rex rabbit.


Black based rabbits are most common, such as in colors like Black, Blue, and Chestnut Agouti. Even though the base itself is a basic black color, it does come in varrying shades—from very dark, jet black to a lighter black). In any breed, show rabbits are selectively bred to be the darker shades of black, those this may matter less in colors that don't show much (or any) of the black base.

Deconfuzzled - Not all black-based rabbits are black. Black just refers to the base, as opposed to chocolate, which is a brown color. In some colors like White or Orange, the base color may not even be visible all the time, so there might be no black parts on the rabbit at all!

Black Based Colors

Chocolate (bb)

A Chocolate Mini Rex rabbit.


Chocolate is a less common and more complicated base than black. It is responsible for colors like Chocolate, Lilac, and Amber. It is known to cause a ruby cast in the eyes, which can help identify a chocolate base in colors that don't readily show the base color.

Chocolate comes in many more shades than black ranging from pale and light to deep and rich or dark and nearly black. In many breeds, dark chocolates are preferred, though it tends to matter less in colors other than straight up Chocolate.

Due to the added pigment of a bright and vibrant chocolate, some breeders prefer a chocolate base in colors that are meant to be bright (such as Orange and Red), which can be made more saturated and v ibrant with chocolate genetics. Likewise, some breeders prefer to use black as a way to ensure that the best modifiers are in place without the leverage of a chocolate base (since it is harder to finf chocolate based bloodlines to breed to, this can widen the prospective gene pool for more quality pairing choices).

Chocolate Based Colors