Light or Dark? Blue is a dilute for black. Dark Brahmas are Silver Penciled. Light Brahmas are Columbian. Either variety can have the blue dilute gene bred in.
Color genetics thread. - Page 53
This is him. He was sold to me as a "Blue" Brahma, but he is clearly something else.
In chickens there are some genes that are basically the "main blue print" for the foundation and main structure. And then there are quite a good number of genes that are "custom options".
Birchen is one of the blue print genes. All by itself, with no other mutations, it turns them mostly black with color on the rooster's hackles, saddle and wing bow patch. The amount of coloring can vary a lot, from practically the whole top of rooster being colored, minus the tail to coloration on just the hackles and some on the saddles. Hens are usually black with color mostly confined to their necks, and maybe some "lacing" on the front breast.
btw the other foundation/blue print genes are extended black(even less color than birchen but there is a lot of overlap where it gets difficult even for experienced persons to visually tell if a bird is birchen or extended black), wheaten, red duckwing(the wild type), and dark brown.
Columbian is one of those custom options you can 'install' in your finished house. What it does is basically clear the main body of black pigments.. restricting it to the hackles, tail and flight feathers.
Light Brahma is perfect example of Columbian's effect. I can't remember if their "foundation" is wheaten or dark brown.. If you magically took away the Columbian gene away from a light brahma, you will suddenly see either a silver wheaten or silver partridge colored/patterned bird.
I'm working on a bantam Phoenix project. We bought a mixed batch of bantam Phoenix several years ago--mostly gold and silver duckwing, but also one white rooster and one white hen. Fast forward a couple of years and we had fawn duckwing show up.
So, the only place the dilution factor (Id) that gave us fawn could have come from was one of the white birds if I understand the genetics stuff I've been reading (and please correct me if I'm wrong!). I suspect they're recessive white since the don't show any dark feathers like I've seen in birds with one copy of the dominant white gene.....
Just to make life more interesting, our last hatches in December gave us fawn, duckwing, and self blue (so lav/lav)....And a very light duckwing type hen with almost no color in her feathers but just enough very pale salmon showing up to tell me she's likely a duckwing based bird with two copies of the Id gene (I think--I've been looking for "sport" or "khaki" samples of fawn and just haven't had much luck finding pix yet).
My understanding of fawn genetics is that it's a codominant dilution factor along the lines of blue--no copies and black expresses fully (as allowed by the e+ gene for duckwing), one copy dilutes the black to fawn, and two copies lightens it further to near white and may also lighten red/gold (hence the near white feathers and very light breast in the sport pullet).
So here's my thinking on setting up breeding pens to try to maximize fawn with the following available birds: fawn duckwing cock, silver duckwing cock, white cock, four duckwing hens, "sport/khaki" duckwing pullet, white hen.
Fawn duckwing cock with white hen and duckwing hen (if the white hen is carrying fawn or other interesting genes it should show, and half the chicks from the duckwing hen should be fawn)
White cock with duckwing hens (again, trying to tease out what he's carrying).
Silver duckwing cock with "sport" hen (so all fawns if she's got two doses of dun factor) and a duckwing hen (I'd like to maintain the silver/gold duckwing line)
I have one gold duckwing cock I've held back--not sure if I want to keep the gold in the duckwing line and the sex linked genetics that go with it or just go with completely silver....
If the suspected lavenders grow up to be decent (they're young yet), I may to a lav to lav breeding next year--or I may cull the birds that have lav genes entirely since I gather lav to dun isn't a good idea....
Any help on this is greatly appreciated!