Golden yellow opaline-pastel (Y-53)
Description: The picture shows a golden yellow opaline-pastel Bourke. It is a cock. The head is pink, the cheek is white. The eyes are red. De beak and the nails are flesh coloured. The primaries are light brown. The secondaries are light brown with a yellow margin. The tertials are yellow and form the change over to the intensive yellow back. The flights have a white triangle. Breast and belly are light rose. The rump is light blue mixed with yellow. The tail is light brown.
Development: The new colourvariety, the golden yellow opaline-pastel is born from a yellow pastel cock, split for opaline and blue and a green opaline hen, split for pastel. In this site I reported earlier about the development of the light green-, light blue- and white opaline-pastel. The golden yellow opaline-pastel belongs to this series.
Namegiving: The name is golden yellow opaline-pastel. The reference colour is a rich golden yellow. The hen is more yellow than the cock because there is less light brown melanin in the flights. It is a nice new colour variety. The yellow colour is more intensive than the yellow colour of the yellow pastel. This is the reason that I did choose this name: golden yellow. The golden yellow opaline-pastel has more contrast than the lutino. The blue colour is preserved in the wing, and the coverts of undertail and underwing. The rump is light blue like the rump of the white-, blue- and green opaline-pastel. The pastel factor is reponsible for the decrease of the melanin. The opaline factor decreases the melanin in breast, belly and back. The combination of the colour with the mutation factors opaline and pastel gives the name: golden yellow opaline-pastel.
Five different colourvarieties of the combination of opaline and pastel factor: Because of this new development we do have a complete series. The pink opaline-pastel was breeded frequently in Holland in the ninethies. The four new varieties are based upon the blue structure factor. I made a survey of the possession of pigments and feather structure of the differen colourvarieties.
|Survey of pigments, melanin and psittacine and the new bluestructure of the five different opaline-pastel colour varieties|
|colour varieties||white opaline-pastel||blue opaline-pastel||green opaline-pastel||gold yellow opaline- pastel||pink opaline-pastel|
|pictures, watch back and rump|
+ Means presence of pigment or structure. None means missing structure or strong decrease of pigment.
The white colourvariety originates by the loss of pigments on the back, the eumelanin, yellow and red pigments. The blue structure does not come to expression by the loss of the eumelanin with exception of the rump,
The light blue colour variety originates by the blue structure and the melanin at the back.
The light green colourvariety originates by a combination of blue structure, a remnant of melanin and yellow pigment at the back.
The yellow colourvariety originates by the blue structure and the presence of a lot of yellow pigment on the back. The blue structure comes to expression only at the rump.
The pink and red colourvariety are missing the bluestructure at the back. The rump is also pink coloured.