i want to do an expirement with my leghorn rooster and silkie chicken breeding them to get a black skin and polished white hen that lays well but go broody often i did the breed not to sure if they can breed true (mabye not) if they dont i dont care nice lair went broody once
cross breeding leghorns and silkies
They will not have black skin, but the males will carry for the trait. (It's a sex linked trait, right?) A male from this cross should produce 50% black skinned daughters when bred back to a leghorn hen. (in theory at least, as I understand it) A silkie rooster over leghorn hen produces black skinned daughters and normally pigmented sons, right?
I think it will take you several generations, a lot of study and culling to get what you are after, but it's not impossible.
There are three loci responsible for the black skin trait or fibromelanosis, therefore the black skin trait is polygenic.
The gene that is sex-linked is called dermal melanin the other locus is fibromelanosis. dermal melanin is a recessive gene, so a male needs two genes to add black pigment to the skin, females only need one of the dermal melanin. The other locus is fibromelanosis. Fibromelanosis is a dominant locus. The third locus is the dominant white skin gene.
If you cross a longhorn with a silkie, all the offspring will inherit one dominant gene for white skin and the fibromelanosis locus. The females will not inherit the dermal melanin from the rooster- the females will inherit the dermal melanin inhibitor gene ( no black pigment in the legs and skin) from the father. The male offspring will inherit one dermal melanin from the hen and one dominant dermal melanin inhibitor from the father.
female offspring will be white skin, one fibromelanosis, and dermal melanin inhibitor - the fibromelanosis locus will not be enough to make black skin
male offspring will be white skin, one fibromelanosis, and one dermal melanin plus a (dominant) dermal melanin inhibitor- males will not have black skin
the only back cross that will produce black skinned offspring is with a silkie or some other black skin breed
Thanks for clarifying this. I had the wrong impression. I'm sure you know what you are talking about....Except that a longhorn is a cow so I don't think you can cross it with a chicken. LOL (autocorrect?)
I remember a post by Nicalandia where he wrote that he felt that the extreme broodiness had been passed from a Silkie rooster to his half Leghorn daughters. I don't know how to find the old post. Generally he was one of the more knowlegable people regarding genetics. I haven't seen him posting for quite a while.