Black Sex-link and Barred Rock chick question......?

[Themellowyellows]

I have heard that barred rocks have a white spot, but the again I think a white spot may be a tell-tale sign for gender in sex-links. I’m not really sure.

Yeah I agree with you. Usually, roo BSL have a white spot on the top of their head.

 

[AinaWGSD]

Hopefully you have 3 barred rocks. Black sexlink females will be solid(ish) black while males will be barred. Barred chicks will be mostly black (or whatever the base color is) with a white dot on their heads. The white barring shows up as they molt their chick down and start growing real feathers.

Barring is a sexlinked gene, it is carried on the Z chromosome (mammal sex chromosomes are X and Y, birds are W and Z). Birds are "opposite" of mammals in that the males are the ones with two same chromosomes. Males are ZZ and females are ZW.
Since the barring gene is only found on the Z chromosome, barred females can only ever have one copy of the gene for barring. Barred males, with 2 Z chromosomes can have either 1 or 2 copies of the gene. So if you take a barred male with 2 copies of the barring gene he will pass one copy of barring to each of his offspring, male or female, because he only has Z chromosomes with barring to pass on.
If you breed a non-barred male (0 copies of the gene for barring) to a barred female (1 copy of barring, on the Z chromosome) all the males will inherit the barred Z chromosome from their mother and a non-barred Z chromosome from the father giving them 1 copy of barring which is enough to make them have barred feathers.. Any chick that inherits the W chromosome (non-barred) from the mother can only inherit a non-barred Z chromosome from the father, so they cannot be barred.

 

[EvieChickenGirl]

okay thank you

 

[EvieChickenGirl]

As they are almost 2 weeks I see barring on the two with white spots on their heads...however the other one...the more grey one, doesn't seem to have it yet....I'm wondering if she's a totally different breed....

 

[EvieChickenGirl]

Update! All females! 2 barred rocks, 2 bsl, 1 rhodie, and 1 no muff easter egger!