Chocolate gene and sexlinkage - can someone explain what I just hatched?

[RememberTheWay]

So I had a pen set up for hatching some color projects. I put what I thought at the time was just a black satin silkie, with some silver leakage in with three bantam Cochin hens (pet quality) Two of the hens were blue and one is a black and white mottled.

The BW hen went broody and I allowed her to hatch out a clutch. Eggs kept being added to the clutch by the other two so I took those and put them in my incubators and moved the other birds to another coop. Then they started Hatching and I got a very large portion of mauve and chocolate chicks. Which in the beginning I assumed had to be pullets and Sex-Linked bc the only explanation would have been that the satin black roo was split to chocolate. Which looking back was Definitely a possibility bc of where he came from. But now that they are growing out I'm not so sure. I know that hens can't carry chocolate they can only either be chocolate or not. I have no chocolate hens here at all. The two Blue hens are very noticeably blue. The hens sire was a black and white mottled bantam Cochin.

Which explains why some of the chocolate/mauve chicks appear to either be mottled or split to it.

I don't know a whole lot about fibro shank sexing but from what I understand if a fibro bird is bred to a yellow or white shanked hen them the F1 babies will be sexable by shank color. All dark shanks will be pullets and all light shanks will be males. I have another pen set up accidentally (porcelain satin silkie project) that from what I've hatched so far appears to be correct for sexing by leg colors. Which brings me to the mauve and chocolate chicks. If they actually are pullets then why don't they have fibro skin? Some of them are light shanks?

I also am seeing on a few of them that they are appearing to get red combs and wattles. They are all less then 6-8wks old . Is there any possible scenario where two Blue hens and a black and white Cochin bred to black split to chocolate roo could produce male mauve and chocolate chicks? I'm totally stumped

I couldn't find any pics on my phone already of the two Blue hens and the dad, so will return and add them here in a bit. Plus will add photos of the reddening+ wattles of the chocolate and Mauve grow outs

 

[RoostersAreAwesome]

Pictures of all possible parents would help
@Amer

 

[Amer]

Okay so the Dermal Melanin gene id+ enables slate shanks, and it is sexlinked recessive. The Fibro gene is autosomal dominant (not sex linked) but fibro is only possible if the chicken has both the Dermal Melanin and Fibro genes. Your rooster is homozygous for the sexlinked Dermal Melanin gene which he will pass to his daughters. However, he must only be heterozygous for the dominant Fibro gene, so only half of his daughters inherit it.

 

[RememberTheWay]

Okay so the Dermal Melanin gene id+ enables slate shanks, and it is sexlinked recessive. The Fibro gene is autosomal dominant (not sex linked) but fibro is only possible if the chicken has both the Dermal Melanin and Fibro genes. Your rooster is homozygous for the sexlinked Dermal Melanin gene which he will pass to his daughters. However, he must only be heterozygous for the dominant Fibro gene, so only half of his daughters inherit it.

So how did I end up with chocolate males without a chocolate hen? They are looking really male now.... I thought of the rooster was the only chocolate parent then only daughters would express chocolate bc they are a hemizygous expression while male must have two copies? Is there a form that is incomplete dominant? Or something that would explain this? Not to mention the rooster only being a carrier and not actually chocolate himself?

 

[RememberTheWay]

Pictures of all possible parents would help
@Amer

I updated the photos

 

[Amer]

So how did I end up with chocolate males without a chocolate hen? They are looking really male now.... I thought of the rooster was the only chocolate parent then only daughters would express chocolate bc they are a hemizygous expression while male must have two copies? Is there a form that is incomplete dominant? Or something that would explain this? Not to mention the rooster only being a carrier and not actually chocolate himself?

Is it possible your rooster isn't black at all and is instead very dark dun?

 

[RoostersAreAwesome]

This hen doesn’t look blue to me, she could be mauve or dun? If she has the chocolate gene and the rooster carries it, they could produce chocolate sons.

 

[Amer]

View attachment 4103784This hen doesn’t look blue to me, she could be mauve or dun? If she has the chocolate gene and the rooster carries it, they could produce chocolate sons.

She does look blue to me...
Mauve tends to be lighter.

 

[Amer]

Actually, I don't know. I haven't seen enough muaves to be sure but I have seen some practically black duns.

 

[RoostersAreAwesome]

She looks similar to the hen in this post, which is apparently mauve (unless I’m misreading it):
https://www.backyardchickens.com/threads/english-mauve-orpington.1593241/