The theory of Mendel's Law when applied to Blue Cuckoo

by the Cuckoo Stud
The insertion of Cuckoo into the equation = note that the Cuckoo pattern can breed out (visually) without careful selective breeding
in both single and double bar factor, however the gene is still present and can present again at any generation

It has taken numerous years and hatching thousands of birds also finite record keeping to finalise with this degree of accuracy
No White birds were used

Double bar factor Cuckoo birds –
% from non Cuckoo bred solid coloured birds – use of Cuckoo bred birds preferred

Cuckoo X Cuckoo = 100% Cuckoo

Cuckoo X Black = 100% Cuckoo

Cuckoo X Blue = 100% Cuckoo - of varying colour/pattern accuracy ranging from Cuckoo to Blue Cuckoo, almost all with blue legs, dark (not red) eyes and mismarked/miscoloured Cuckoo

Slate Cuckoo X Slate Cuckoo = 100% Slate Cuckoo

Slate Cuckoo X Cuckoo – 50% Slate Cuckoo 50% Cuckoo

Slate Cuckoo X Black = 100% Slate Cuckoo

Slate Cuckoo X Blue Cuckoo = 50% Slate Cuckoo 50% Blue Cuckoo

Slate Cuckoo X Blue or Splash = 50% Slate Cuckoo 50% Blue Cuckoo - of varying colour/pattern accuracy with blue legs, dark (not red) eyes and mismarked/miscoloured Cuckoo

Blue Cuckoo X Blue Cuckoo = 100% Blue Cuckoo

Blue Cuckoo X Black = 100% Blue Cuckoo  - varying depth of colour some exhibit black legs and miscoloured eyes

Blue Cuckoo X Blue = 100% Blue Cuckoo - varying depth of colour, blue skin/legs, dark and miscoloured eyes, Blue being dominant


Single bar factor Cuckoo birds –

Solid colours from Cuckoo carry Cuckoo

% from non Cuckoo bred solid coloured birds – use of Cuckoo bred birds preferred

Cuckoo X Cuckoo = 50% Cuckoo, 50% Black - predominantly Cuckoo males Black females

Cuckoo X Black = 50% Cuckoo, 50% Black - predominantly Cuckoo males Black females

Slate Cuckoo X Slate Cuckoo = 75% Slate Cuckoo/Cuckoo, 25% Black = Black females

Slate Cuckoo X Black = 50% Slate Cuckoo, 50% Black = Black females

Slate Cuckoo X Blue Cuckoo = 50% Slate Cuckoo, 25% Blue Cuckoo, 25% mix of Black, Blue, Splash = Splash rare and usually females

Blue Cuckoo X Blue Cuckoo = 12.5% Blue Cuckoo, 12.5% Cuckoo, 25% Black, 25% Blue, 25% Splash - solid Black & Blue being dominant over the Blue Cuckoo pattern

Blue Cuckoo X Blue = 75% Blue, 12.5% Blue Cuckoo (being Black based but Blue dominant), 12.5% Black and/or Splash.
All non Black solid colour birds and 50% of the Black birds will have blue/mottled skin/mismarked feather and/or skin colouring rendering them useless for breeding – progeny from this colour mating eg Blue Cuckoo X Blue Cuckoo (from Blue Cuckoo X Blue) will breed an even higher % Blue

This same % follows for other Cuckoo colours from single bar factor birds

replace *Blue/Blue Cuckoo* birds for Lavender/Buff/Red/Chocolate etc solid or Cuckoo birds as needed

the best Cuckoo X Cuckoo bred solid coloured offspring should be retained to breed back into the Cuckoo to help maintain depth of colour –
% change once this happens – a couple more years are required to finalise the solid colour carrying Cuckoo %

# subject to copyright laws of Australia