Sex Determination Of Your Duck Eggs
📌 Sex determination and sexual differentiation in the duck world.
The XY sex-determination system is a system used to classify reproduction in many mammals, including humans, where the sex of any offspring is determined  at fertilization by the sex chromosomes. So the sex of an individual is determined by a pair of sex chromosomes.
Females have two of the same kind of sex chromosome (XX).
Males have two different kinds of sex chromosomes (XY).
In humans, and most mammals, the offspring have a combination of two sex chromosomes per offspring. With two XX chromosomes, one from the male and one from the female, the offspring will develop into a female, and an offspring with an XY chromosomes will develop in to a male.
So it is the male that determines the sex of the offspring in humans.
Well not the case in a Duck - they have their own system called  the ZW sex-determination system.
We should note that the ZW sex-determination system of birds is unrelated to the XY sex-determination system of humans.
For Ducks, the males ♂ have two long Z chromosomes (ZZ) and females ♀ have one long (Z)  chromosome and a smaller (W) chromosome as showns.
The female, when in lay, regularly produces two kinds of embryos - a Z embryo and a W embryo. When the embryo is fertilised she goes on to produce either a female egg, with two ZW chromosomes  or a male egg with two ZZ chromosomes.
The W chromosome being smaller in size carry very few genes but the Z chromosome is well equipped in this respect, and carries significant Z-linked (Males) genes.
In Ducks the female determines the sex of the chick.
