Just wondering. What is a sex link?

[Kim_NC]

The short version answer...
The barred gene will be passed from the hen on the Z chromosome with the B (barring gene) to males.

And a longer explanation for anyone more curious....
Female chickens have a Z (long) chromosome and a W (short) chromosome. This makes her set of sex chromosomes represented as ZW. Because it is longer, the Z chromosome has gene locations that the W chromosomme does not.

Male chickens have two Z sex chromosomes...or ZZ.

In this case, the barred gene is carried on the Z chromosome, but not the W chromosome.

So...
If you cross the Barred Hen to a pure Black Ameraucana Roo, the female offspring end up with a W chromosome without a barred gene from the hen. Therefore all females will be non-barred.

Males on the other hand will get a barred gene from the hen's Z chromosome. Therefore all males will be barred.

I'm sure this is correct. I already make this cross and know the sexlinking works. It also works with Black Australorp Roo x Barred Rock hen.

 

[Davaroo]

That's impressive, Kim! Great explanation.

Someone also mentioned this up thread, but it bears repeating:

Not only can you tell males from females at birth, but being hybrids, sex-links are more vigorous and typically lay better than the parent stock. The sum being greater than the parts, in a manner of speaking.

Now for the bad news: When SL's reproduce, they tend to revert back to the parent stock and lose these good traits in only a few generations. In fact, they often become worse, unless stringent selection is employed in breeding the succesive generations.

 

[Kim_NC]

Thanks for the compliment, Davaroo. And I agree with your other comments (and those above) about hybrid vigor. LOL...I make the pure Ameraucana /BR cross to get a vigorus, better laying EE. This results in green eggs from the offspring of course.

Yeah...a shame the sexlinking and the traits for vigor aren't carried forward well through the generations. C'est la vie

 

[Davaroo]

Quote:
I'll see your "c'est la vie," and raise you one Coq au Vin.

 

[Neil Grassbaugh]

Did you know that virtually all of the commercial white feathered terminal generation egg and meat type chickes are also sex links?

They are "feather sexable" at day old.

The cockerels have shorter wing feathers of equal length and the pullets have both longer and shorther wing feathers, usually alternating.

 

[Davaroo]

Thats right, feather sexing is another way to use sex linked traits (which is what the term really means). It isn't commonly thought of when you mention sex links, as most people relate to the color angle.

Feather sexing is a bit of a "technique," as I understand it, and is reputedly not as reliable as the coloration of the feathers. I believe fewer breeds carry the feather sexing trait.
I have little experience on the subject, so am just regurgitating what I've read.

 

[Mahonri]

Quote:
I did not know that!

Learn something new everyday.

 

[Kim_NC]

This page has a good explanation of 5 basic groups of sexlinking possibilities. Includes feather color, feather length/growth, leg color:

http://www.users.on.net/~greggles/sexing.html

 

[Kim_NC]

Quote:
I'll see your "c'est la vie," and raise you one Coq au Vin.

Oh, we love Coq au Vin! I cheated last time though and made it from a succulent Cornish X instead of a roo.

Neighbors loved it however...they were over for supper that evening.

 

[SportTees]

Quote:
Thanks- I have been looking for an answer like this- chicken genetics