COLORS inheritance
black brown

THE BLACK AND BROWN GENE
The Bb pair - all cockers have one or the other of this pair of genes which means that all of these dogs are basically black or brown (chocolate) all other colors are color modifiers.B - produces solid black and is dominant
b - restricts (dilution) the black color and produces brown (chocolate/
liver) and is recessive
The B pair of genes are inhereted independently of all other genes inclusive of the A series.

The easiest way to tell if your cockers primary color is actualy black or brown regardless of coat color is to check the color of the nose and toenails if  black the primary color of the cocker is black
if brown the primary color is brown
Disregard toenails that are white 
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