how to hatch out silver blue birchen?

[Turtle1626]

Can I work my way to blue silver birchen Cochins? I have two lemon blue Cochins and BBS cochins.

 

[NatJ]

Can I work my way to blue silver birchen Cochins? I have two lemon blue Cochins and BBS cochins.

Yes, if the BBS have the Silver gene. They could have either Silver or gold or some of each, and as long as none of it shows, you can't tell. If you can find a black or blue that shows clear Silver leakage, that would be a good bird to start with. (On a Splash, it would be harder to tell if the chicken is showing Silver, or just light because of being Splash.)



You should be dealing with three main genes:
The blue gene (Black/Blue/Splash), which is already in both groups and will behave the same as it always does.

Extended Black (in the BBS), which is dominant over Birchen (in the Lemon Blues).

Silver/gold (sexlinked gene located on the Z sex chromosome, with Lemon Blues being gold, and BBS hopefully having Silver.)


To deal with Extended Black vs. Birchen, cross the two, then choose a chick and breed back to the Birchen (Lemon Blue) side. Half of chicks should show Birchen, the other half show Extended Black. Keep the Birchen ones for your project.



To move the Silver gene into a line of gold birds (the Lemon Blues), you will be working with three kinds of crosses:

Cross a Silver male with a gold female, all daughters will be silver, with all sons showing Silver and carrying gold.

Cross a Silver hen with a gold rooster, all sons will show Silver and carry gold. (Daughters of this cross are just gold, not useful for your project.)

Cross a male that shows Silver but carries gold to a gold female, and you will get a 50/50 split of chick types. Half of daughters will be gold and half will be Silver. Half of sons will be Silver carrying gold, and the other half will be pure gold. The silver hens and the Silver-carrying-gold roosters are the ones you need to continue the project.

The first cross can go either way (Silver male to gold female, or Silver female to gold male). Pick according to what birds you have and/or what is convenient at the time, or even do both and have two lines going at once.


You should be able to do the Extended Black and the Silver/gold at the same time. Do the Silver/gold part, but the first cross has one from each breed (Extended Black x Birchen), and the next cross is going back to Birchen (Lemon Blues). So that second generation, crossed back to Lemon Blues, should give 50% Birchen chicks, and you pick through them to find the right ones for the Silver/gold part of it (probably about 1/4 to 1/8 of the total chicks in that batch.)

Once you have some that are Birchen and Silver, you can keep breeding them with the Birchens and just keep track of the gold/Silver until you have a large enough flock with Silver to just breed them with each other.

To get a pure Silver male, cross a silver hen with a rooster who is Silver/gold split, and half of the sons will be pure for Silver, with the other half showing Silver but carrying gold. You may be able to tell splits vs. pure Silver roosters by sight, or you may have to test-mate a few and see. To test mate a rooster, cross him with a gold hen (any gold daughters or gold sons will prove that he carries the gold gene) or cross him with a silver hen (gold daughters will prove that he carries the gold gene, but all sons will look Silver anyway.) From either of those tests, Silver hens can be added to your Silver flock, even if their father carried gold. If you use a Silver hen for the test, and the rooster proves to be pure for Silver, then of course all the chicks will also be pure for Silver.

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One major point that could change this:
Some Black/Blue/Splash chickens are genetically Birchen rather than Extended Black. They look solid-colored because they have a bunch of other genes, each of which spreads the black further and restricts other colors.

If your BBS birds have that, then crossing to get rid of Extended Black is not going to work right. Instead, start on the Silver/gold part of the project, crossing them into the Lemon Blues repeatedly, and in each generation select the ones that show the most Silver.

Chicks with the Extended Black gene are often colored like penguins: black on top, yellow underneath. Birchen chicks seem more likely to be black all over (yes, this seems backwards, given the adult colors.) If you know how the chicks of the BBS line look, you may be able to tell if they have Extended Black before you start making any actual breeding decisions. If you are starting with adult birds and don't know what color they were as chicks, make your first cross and look at what those chicks look like at hatch.

 

[member 544621]

I'd love to see photos of the birds, for my own reference.