Araucana Crosses: What colour will eggs be?

[Norman]

I have 2 Araucana Cross pullets (1 with Jersey Giant, 1 with Sussex) and my question is will their eggs be blue/green or a muted olive or brown/cream? Or...do I jut need to wait and see? I dont really know how the genetics work for egg colour. Is the green/blue a dominant or recessive gene?

 

[MaransGuy]

You are dealing with two different egg color types here. The blue EE egg shells are pigmented all the way through while typical brown egg layers only have the outer layer of shell pigmented. When crossed you typically get a blue base color and then the depth of brown from the other bird will determine the shade of olive on the surface.

 

[tadkerson]

Norman,

White shell color is recessive and is o+/o+. It takes two white shell genes for a bird to lay white eggs. They can not have any other genes for egg color.

Brown egg shell color is polygenic. There are several genes that cause brown egg shell color. These genes are dominant. They could also be recessive. No body knows very much about the genes that cause brown egg shell color because it is complex.

When a bird has two white shell genes and a number of brown egg shell genes the eggs will be brown.

Brown tinted eggs are produced by a bird that has two recessive white shell genes and a few of the brown egg shell genes.

Blue egg shell color is caused by a dominant trait so a bird can have one or two blue shell genes. O/o+ or O/O

Green egg color is codominant. The brown egg shell genes and the blue egg shell genes are both being expressed so you get a green egg.

As Marans Guy stated, the blue pigment is added to the shell and the brown pigment is placed on the outside of the shell- bingo a green egg shell.

Tim