Cochin Wing Sexing? True or False or what?

[Reurra]

So i read that fast growing wing feathers mean girls and slow growing wing feathers are boys. Is this true or does it vary by genetic lines?

I picked up 5 and 3 have longer wings, while 2 still havent feathered.

Just curious as this is my first experience with Cochins!

 

[The Moonshiner]

Its a sex linked trait.
For it to work you have to breed a fast feathering male to a slow feathering female.
The only way it would work with any purebred is if the breeder had two separate lines. One fast feathering to produce breeder males and one slow feathering line to produce breeder females.
That would mean three lines of the same breed and variety.
I can't see anyone maintaining a breed like that just for feather sexing purposes.
Every feather sexing I've see were produced by crossing breeds to make hybrids.
It is the standard for the broiler industry.

 

[Ridgerunner]

It's genetics but not genetic lines. The very first post in this thread explains the science behind it.

http://www.backyardchickens.com/forum/viewtopic.php?id=261208

If the mother has the dominant slow feathering sex linked gene and the father is pure for the recessive fast feathering gene the chicks can be sexed at hatch. The hen only has one copy of the sex linked gene which she gives to her sons. Her daughters get nothing from her. The rooster has two copies of that gene, he gives one at random to all his offspring. So pullets from that cross will get a fast feathering gene from their father, nothing from their mother, and feather out faster. Cockerels get both a recessive fast feathering and a dominant slow feathering gene. The dominant gene wins and the boys feather out slower.

This only works for one generation. In the next generation the females have the recessive fast feathering and the male have one of each. Both of these are wrong for feather sexing or any type of sex linking.

 

[Reurra]

Ok, so it would be unreliable in this case then? The family of birds I got them from are somewhat interbred I believe, and are pure as far as Im aware.

 

[Ridgerunner]

Yes it would be unreliable.

 

[Reurra]

Ok thanks! Just wanted to be sure before I got my hopes up!