I am trying to get this all straight: cuckoo's are NOT supposed to have Er/Er genotype. E/E is preferred? Is this for silver cuckoos only or golden cuckoo as well. My understanding is that BCMs (not cuckoo) are usually Er/Er genotype. So does this mean you cannot cross a golden cuckoo and a BCM and get females that are true BCM or golden cuckoos? (depending on who is the roo and who is the hen in the cross)Hi, your hen looks like she has carrying birchen, did you notice the lacing on her hackle feathers? Her pattern is also affected by it. I am not picking on her but using her as an example of one that has been crossed. That is how you can darken their eggs is by crossing them to a birchen, funny enough you get the silver birchen from a silver cuckoo but you have to have a silver cuckoo to get a silver birchen!
This is a great example of what a cuckoo hen should look like. It is from the Marans Uk site so of course she has clean legs!
Notice how she is dark and uniform all over with no trim or highlights in the hackle. Her pattern is consistent but the bars do not line up like a barred rock.This is what a black based or E/E hen with the barring gene should look like.
This pair in my opinion is just beautiful especially the roo.
The males also need to be uniform in pattern and color from head to toe.
These are Silver cuckoo notice the hackles of the hens are almost birchen like and the roo is almost white in his hackle and pyle. These are carrying the birchen gene or ER/ER
When you cross the two you get something similar to your hen in the picture. The roos will also have the lighter hackels and can also show the metallic sheen in their dark bars.
