sex-linked?

[nychicken]

I literally just started on this obsession yesterday and I have already seen a lot of reference to "sex-linked" chickens. What does this mean? I have not been able to find a definition.

 

[WoodlandWoman]

This link will explain it. If you cross certain breeds, their chicks can be sexed as soon as they're hatched, because the males and females have different feathering. The look of their feathers is linked to what sex they are.

http://www.feathersite.com/Poultry/CGP/Sex-links/BRKSexLink.html