E/E or ER or ewh or eb .....

[Guest]

I\'ve been doing a little research into the genetics of color and have just realised (HA!) that not all blacks are created equal. Of course I should mention this is a problem for every breed. Down to my question, do any of you do cross mating to test your blacks to make sure they are E/E? What is the most useful cross as this is the domiant E-locus?

[grisaboy]

Well they could be E or they could be E^R and possibly (but not likely) even e^b.  I don\'t think there is any requirement that they be one or the other as long as they meet the color standard.  I don\'t know of any advantage or disadvantage of being E or E^R in most matings, either would work. Someone else may know why one would be preferred over the other.
That said,  I think you can tell by the down color of the baby chicks.  At least my modern game chicks (Proven to be E^R) are usually solid black when hatched.  The black ameraucana chicks usually have a white belly.  I don\'t know for sure that these have E genes, but they sure look different than my moderns.

Curtis

[Guest]

I think it only becomes important when crossing to work with other colors, and to understand more of what pops out/up occasionaly.
Do you get a brown head on your ER chicks? DO you have other colors, like Id, in your modern games?

[John]

Do you get a brown head on your ER chicks?

I know the question is for Curtis, but will give some input.  I don\'t get brown on the heads of my brown red chicks, but do on the black gold chicks.

E^R) are usually solid black when hatched

I have photos of mine posted on the Photos page of the ABC site.  My bantam brown red chicks seem to have more white than the LF which hatch from mostly black to solid black.
I don\'t know for sure if they are E^R/E^R.

[grisaboy]

I have modern game bantams in black, birchen and brown red.  All are genetically E^R.
All hatch out solid black, except occasionally the brown red chicks will have a brown face.  
All of my moderns have black or slate legs so Id is not an issue.
They are really pretty easy genetically as all I really have to worry about is gold (ss) versus silver (SS) when I cross brown reds and birchens.

Curtis

[Mike Gilbert]

My best brown red chicks hatch out solid black, with maybe just a little grey in front.    I think, at least in my line, those that hatch out with white or yellow chests are split at the e-locus for E and E>R.     The best blacks seem to hatch out with quite a bit of yellow chick down.   I have heard Wyandotte breeders say those turn out to be the best colored blacks.

Mike

[Guest]

Thanks for good information!
Curtis, I should have written out Dunn instead of Id as this is what I am curious about and one of the colors common to American/Pit game and a color I may have in my blues.
Mike, do you mean the best blacks have some yellow down or yellow and white? I remember a reference to \"peguin\" being possibly an indicator of ... something. The endless quest!

[Guest]

Mottling on extended black produces a penguin chick.


Testing a bird for extended black.

Cross a black bird with a  bird that is columbian restricted. If the  offspring, as adults,  have black plumage on their body the black bird is carrying extended black. If the black bird is  black because of black intensifiers and another e locus then the bodies of the offspring will be columbian restricted.

Rooster

[Guest]

I think most Ameraucana blacks, at least my new guys from Paul Smith, are from black/blue breeding, so will have Co as it improves lacing. Would there be any difference in hetero or homozygous Co on E/? or ER/? ?

[Guest]

Rose,

The columbian gene  has no effect upon the extended black gene. An extended black bird can have a black body and the Co or columbian gene will not clear the body of the black.
Heterozygous or homozygous Co have no effect upon the extended black.

The columbian gene does effect the expression of black in the bodies of ER or birchen chickens. The columbian gene will clear the black from an ER chicken. Heterozygous and homozygous Co are both relatively effective on ER. Heterozygous Co on females may be expressed as more black stipling on the back than on a homozygous Co bird.

Rooster