The female reproductive tract of chickens consists of a pair of ovaries and oviducts. The egg travels through the oviduct over approximately 22 hours, undergoing several modifications. It passes through the infundibulum, where it is engulfed. In the magnum, albumen is deposited on the egg. The isthmus adds two shell membranes. In the uterus or shell gland, calcite crystals are deposited to form the eggshell. A protective bloom coating is applied in the vagina before laying.

4. Female Reproductive Tract
 Ovary
 Infundibulum - site
of fertilization
 Magnum - albumin
addition
 Isthmus - membranes
 Uterus - shell gland
 Vagina - transport to
exterior
 Sperm storage occurs at
various sites in tract in
some species

5. Animal Structures
Female Genital:
A female reproductive System
is usually composed of a pair of
ovaries and a pair of oviducts.
Chickens and most other birds have
only one ovary and one oviduct.
Ovary:
Organ in which yolk formation occurs; yolk
is formed in the follicular sac ovarian follicle
by the deposition of continuous layers of yolk
material; ninety-nine percent of the yolk
material is formed within the 7-9 days before
the laying of the egg.

6. Oviduct:
The egg moves through the oviduct for about 22 hours.
During this journey it undergoes a number of modifications. First, a
thickened outer layer is applied to the vitelline membrane, which
has two cord-like extensions, chalazae, which anchor the yolk in
center of the egg and stabilize it.
Infundibulum:
Also called funnel; the first section of the oviduct
that quickly engulfs the yolk with its thin, funnel-like
lips.

8. Magnum:
After passing the infundibulum the yolk quickly
enters the magnum section. The albumen is applied to
the outer surface of the egg providing water, nutrients,
and antibiotic agents. The shape of the egg is largely
determined in this section. The magnum is separated
from the isthmus by a narrow, translucent ring without
glands.

9. perivitelline
Infundibulum Ovary membrane
Avian
Female
chalazae
Anatomy
albumen
Magnum Oviduct shell membrane
Isthmus
Shell Gland
Uterus
Intestine
cleaving blastodisc
24 hrs
50K cells
vagina
Right
Oviduct
cloaca
shell
Left side of Reproductive Tract Develops!!

10. Isthmus:
Isthmus is smaller in diameter than the magnum.
It is here the two shell membranes are added. The
membranes touch each other throughout the egg,
except at the blunt end of the egg, where the air cell
is formed later because the egg content cools down
and contracts after laying.

11. Uterus:
Also called shell gland. In this portion of the oviduct,
calcite crystals are deposited in and over the outer shell
membrane layer to form the eggshell.
Vagina:
In the vagina, a thin, protein coating called "bloom"
is applied to the shell to keep harmful bacteria or dust
from entering the egg shell pores. The egg is turned
horizontally (the process called oviposition) just before
laying so that egg will exit with blunt end first.

12. Chicken Tract
Ovary
Magnum
Intestine Shell Gland

13. Chicken Ovary
Hierarchal
Follicles

14. Ovary with
large follicles
removed
Ruptured follicle

15. Isthmus
Infundibulum
Magnum
Shell Gland
Chicken Reproductive Tract
Cloaca Follicles

16. Infundibulum

17. Vagina
Vaginal
opening
Cloaca Intestine
opening

18. Vagina
opening
Cloaca of Chicken