EGG color genetics

[Duck Hill]

On this thread, please post anything and everything having to do with egg color genetics.

 

[Duck Hill]

Some ducks lay green eggs and some lay white eggs.

Two sisters:
Dad is a Welsh Harlequin; he has genes for white eggs.
Mom is an Indian Runner and lays green eggs. Her mom laid white eggs, so she must have gotten the green egg gene from her dad. Mom therefore had a white egg gene and a green egg gene, and she lays green eggs.
Sister 1 lays a white egg.
Sister 2 lays a green egg.

This is consistent with dad having a white egg gene, mom having a white egg gene and a green egg gene, and green egg being a dominant gene.

However, my sample size is extremely small. What have you observed?

 

[ANightPerson]

Green/blue eggs are dominant to white eggs. These are the only two alleles in ducks, with some laying eggs with a coating over them (like Cayugas.) The coating is secreted onto the egg in the shell gland before it comes out and is easy to scratch off, unlike white or blue eggs which are the natural color of the shell due to the fluid in their uteruses. Usually the coatings will be brown or black. The genes of the brown/black coating genes are still under investigation, but are believed to be dominant, and possibly sex-linked. Personally, I've never bred ducks with brown/black eggs. I'm planning on testing it out with Cayugas and Pekins hopefully soon. Possibly I'll add in some blue egg genes and see what I get.