Agriculture Reference
In-Depth Information
THE HEN'S REPRODUCTIVE SYSTEM
Once ovulation occurs, the egg is caught in the
infundibulum,
which is the first part
of the oviduct. Ovulation occurs daily for most of the year, except during molting and
feather regrowth. Sperm storage areas are located in the infundibulum, where fertiliz-
ation takes place and the first layer of
albumen
(protein component of an egg white,
called the
chalaza
(spiral cord between egg yolk and lining membrane), is produced.
This whole process takes only about 15 minutes.
Next, the yolk passes to the
magnum
, the largest part of the oviduct, where most of
the albumen is formed and deposited around the yolk. The time spent in the magnum
is about 2 to 3 hours. After the magnum comes the
isthmus
, where the inner and outer
shell membranes are formed. The time spent here is about 1.5 hours.
The last stage of egg production is the longest: the egg's development in the
shell
gland
or uterus takes between 18 and 21 hours. Here the egg takes up salts and water,
and the final part, the hard shell, is added. The
cuticle layer,
the thin protective layer
on the outside of the egg (very obvious in duck and goose eggs, but harder to notice in
chicken, turkey, and guinea eggs), accumulates over the shell and then the egg passes
into the vagina, where it turns 180 degrees so that the large end comes out first.
