Genetics of blue feather color

[Kickingbird]

The gene for blue (Bl) is incompletely dominate and inhibits black. The gene for blue and the gene for the extention of black are independent of each other. In other words you can have a bird that is pure for black (E,E) and has one blue gene (Bl) and this gives blue. If two genes for blue are present (Bl,Bl) Then the bird will be white with blue splashes (can look nearly all white). However is black at the same time....the black is just hidden by the blue gene

Here are the expected outcomes for blue breedings (Genetics of fowl, F.B. Hunt)



Blue x Blue--> Black 1, Blue 2 , Blue splashed white 1
Bl-sp x blue -->Black 0, Blue 1, Blue splashed white 1
Blk x Bl --> Black 1, Blue 1, Blue splashed white 0
Bl-sp x bl-sp--> Black 0, Blue 0, Blue splashed white - All
blk x blk --> Black- All , Blue 0,Blue splashed white 0
Blk x Bl-sp --> Black 0, Blue- All ,Blue splashed white 0

[Kristen]

I am curious as to where you found your info on the blue genes. I have always thought it was an allele of the black gene and that a blue splashed white bird did not carry a black gene. Page 190 in F.B. Hutts book shows the cross between an F2 generation out of an original blue splashed white Andalusian crossed with a white Leghorn. It seems that if there were black genes carried by the blue splashed white Andalusian that the ratio of blacks in the F2 generation would be slightly different. I don't know, I was just wondering.
Kristen

[Kickingbird]

Kristen,

Good question.

On page 187, the first paragraph, Hunt says :

"The important points to remember are that the blue-splash white is homozygous, and that the blacks from Andalusions are in no way different from any other black fowl so far as color is concerned"

Then on page 190 he states: " Since both parents are CC, their genotypes may be shortened to ii Bl Bl for the homozygous Andalusians and II bl bl for the White Leghorns.

Stay with me here!

Then go back to page 168 under the heading "Solid Colors: Black" Third paragraph: " The symbol generally used to designate the presence of black pigment of any kind is C (color), but birds with solid black must also carry a gene, E, which permits extension of color to all parts of the plumage"

To make a long story short I know this from breeding and classes in genetics. However I wanted to show you how convoluted color genes are and that the answer is in Hunt's book, it just takes some cross referencing.

On page 190 when Hunt says "Since both are CC" He is saying that both birds are pure for the black gene. In addition the Andalusians are ii, for non-dominate white and Bl Bl for blue splash white.

Does this make sense? If not let me know and I'll dig further for you.

Mark

[Kristen]

Yes, that makes sense now...I worked it out on paper so I could see it...thank you! Wow, I guess I never pictured a Splash bird still being Black in a sense, lol.
-Kristen

[Sodapop]

So, if I breed a black from a blue family, to a black from a black family, the offspring will be pure Black?

[Kickingbird]

Yes, as far as they will not be blue in any way. There may be other factors that will make them show some color such as birchen or brown-red. The extention for black that makes a bird solid black is a dominate gene. Therefore if they only have one of these genes about 1/2 of the offspring will be solid black and 1/2 will have some sort of coloring in the hackle feathers either silver or gold (red).