Chocolate Orpington question

[Isaiah53]

So I understand from another thread, that
"A chocolate male over a black female produces black cockerels and chocolate pullets, while the other way around makes all black offspring."

But I don't have an all chocolate male,
I'm trying to figure out how I managed to get these chocolate pullets when I had a chocolate cuckoo Orpington rooster and a blue Orpington rooster only. My hens were either chocolate or black, white or barred if that helps.

Any ideas how that happened? I thought cuckoo pattern was dominant so all chicks would be barred/cuckoo? Forgive my ignorance, any information is appreciated.

 

[sylviethecochin]

1. Is your rooster double-barred or single-barred?
2. Is there any chocolate heritage in your blue rooster's background?

 

[Ridgerunner]

I have to be careful with this, the terminology can trip me up. Chocolate is a recessive gene that is also sex linked. As I understand it, chocolate only affects feathers that would normally be black. So basically the default for not-chocolate is black. But black is controlled by other genes contrasting with red. Every other color is basically a modification of red or black, so I'll try to simplify and hope the genetics gurus don't beat me up too badly.

If you have a chocolate hen that gene will go to her boys only, her daughters will not get anything from her. So to get a chocolate pullet that gene has to come from her daddy. So your Blue Orp rooster is not the father of those pullets, the chocolate cuckoo Orp is unless, as Sylvia said, the Blue Orp has chocolate in his background. Then it could be either male.

Barred is also a sex linked trait. If a hen is barred she only gives that to her sons, her daughters don't get that from her. Since you are talking pullets, any of your hens could be the mother, even the white as there are combinations that would make her white but give a not-white offspring.

If that cuckoo rooster was pure for barring he would give a barred gene to all of his offspring, male or female. Since barring is dominant they would show barring if they had it. That means he is not pure for that gene, pure meaning that both genes at that gene pair are the same. That means he has one gene at that gene pair that is barred and one that is not. The chocolate pullets inherited the not-barred gene. Or if the Blue Orp has chocolate in his background he could be the father and barring does not come into it.

So basically it could be any rooster and any hen. It depends on the genetic mix and how recessives go together.

 

[Isaiah53]

So the chocolate cuckoo has been culled, sadly, but I believe he was single barred, but picture attached. Yes, he lost feathers around his neck from letting the hens peck out his feathers. Baldy is no longer with us.

Randy the blue rooster may have chocolate in his background but I can't be sure. I did get several chocolate chicks with red leakage on their wing feathers this year. So far they look like pullets and not cockerels.

So I guess I will just appreciate what they are!

 

[Sneebsey]

Do you have photographs of the father? I agree with @Ridgerunner and @sylviethecochin that there is question as to his purity for the barring gene. He will appear darker than a male pure for the gene, though the chocolate may complicate things there.

A second possibility is the dun gene, which is phenotypically very similar to chocolate, but is incomplete dominant, like blue; two doses is khaki, one dose is dun. I am sure I read on here about someone finding a dun in their line of chocolate somethings, though I cannot recall who or where.

ETA: Apologies; you posted photos while I was typing. The white areas in his plumage are unusual and I can't think what could be causing it. I wouldn't expect him to show his ground colour on his tail, so something is likely diluting the black other than or in addition to chocolate.

PS: He is dark-barred, impure for barring, so half his offspring will be solid.

 

[Isaiah53]

Do you have photographs of the father? I agree with @Ridgerunner and @sylviethecochin that there is question as to his purity for the barring gene. He will appear darker than a male pure for the gene, though the chocolate may complicate things there.

A second possibility is the dun gene, which is phenotypically very similar to chocolate, but is incomplete dominant, like blue; two doses is khaki, one dose is dun. I am sure I read on here about someone finding a dun in their line of chocolate somethings, though I cannot recall who or where.

I added photos in my other reply of the potential fathers. Here are pictures of the "chocolate" offspring. I think they are all pullets, but the first two are about 4 weeks older and have no leakage, they're also huge. Both parents are Orpingtons.

 

[Isaiah53]

But....
I think it's time to downsize. Now I wonder if the first two pullets are not crossed with an Ameraucana hen, but I doubt they'd be that big if they were.

Anyway don't want to waste everyone's time. I really do appreciate your answers, many many thanks to you all.