Out of curiosity: When is the sex determined?

[PeppermintHen]

From sperm to yolk in the whole fertilization process when is the sex of the chick determined? Is it done before the eggs is laid, or when the incubation starts? Thanks -- Yvette

 

[ChickenCanoe]

In general it is at insemination. When the sperm joins the egg.

 

[tls_ranch]

I believe the sex is determined by the hen with each egg...not the rooster's sperm. Chickens are not like humans where the male XY chromosomes determine the sex of the offspring at fertilization, in birds it's the female that controls sex by the Sex Chromosomes Z-W.

Trisha

 

[ChickenCanoe]

I believe you're right Trisha. Birds system of sex determination -ZW in which it is the females that are heterogametic (ZW), while males are homogametic (ZZ).
That said, I think it's a done deal once the egg is laid.

 

[cashdl]

The sex of the chick is determined when the hen add her genes to it. If she adds the W chromosome it will be a pullet if she ads a Z chromosome it will be a male. To be a male it has to inherite the z chromosome from the hen.

Lanae

 

[srpaint]

Cool info to know!

 

[PeppermintHen]

Thanks to all of you, you answered my question.