Crossing a BB male with a Bb female:
The Punnett Square will look like this:
BB BB
Bb Bb
The percentage will be as follows:
- You will have 50% homozygous dominant (BB)
- You will have 50% heterozygous (Bb)
Now, for the phenotype, you will have 100% black fur, since B is dominant and is prevalent in 100% of all the breeds.
For the genotype, you have 50% BB and 50% Bb