Black family rabbits are either “BB” or “Bb.”  Unless you see a chocolate color in a rabbit’s pedigree, it’s fairly safe to assume it is “BB.”  Chocolate family rabbits are always “bb.”  And chocolate family rabbits cannot carry the black gene “B.”  That’s it.  All Lops, Mini Rex, Dwarfs and all other breeds are either “BB,” “Bb”, or “bb

 

The black-chocolate color genes are very straightforward.  There are only three combinations (“BB,” “Bb,” and “bb”)