What inherent genetic requirement forces breeders to maintain a three-color flock to preserve the blue variety?

Answer

The blue coloring is a dilution of the black gene and the breed does not breed true.

The blue color results from a dilution of the black gene, meaning mating two blue birds yields a mix of blue, black, and splash offspring, necessitating the maintenance of all three colors for consistent blue progeny.

What inherent genetic requirement forces breeders to maintain a three-color flock to preserve the blue variety?
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