Female Reproductive Tract

Structure of the Female Reproductive Tract

-ovaries

-oviducts

-uterus

-cervix

-vagina

-external genitalia

Layers of the Female Reproductive Tract

-outer serosa

-muscularis

-submucosa

-mucosa

Outer Serosa

single-layer of squamous (flattened) cells

-outer surface of the repro tract

Muscularis

Doubled layer of smooth muscle

-outer longitudinal layer

-inner circular layer

Function of Muscularis

contraction

-helps push sperm up the repro tract and egg down the repro tract

Submucosa

layer of the female repro tract containing blood vessel, nerves, and lymphatics

-support tissue

-mucosal layer

Mucosal Layer

Secretory layer

-made up of epithelial cells

Function of Mucosal Layer

changes with location

-in oviduct there is ciliated and non ciliated.

-> ciliated pushes egg along the tract (allows movement)

-> non ciliated produces fluid

Broad Ligament

surrounds reproductive tract

-vascular supply

-lymphatic drainage

-nerves

-supports tract

Parts of the Broad Ligament

mesovarium, mesosalpinx, mesometrium

-continuous with peritoneum

-all same tissues -> just support different parts

Peritoneum

membrane that lines the abdominal cavity

Mesovarium

attaches to and supports the ovary

-contains blood and lymphatic vessels and nerves

-"Hilus" of the ovary

Function of Mesovarium

holds the ovary

Mesosalpinx

supports the oviduct

-thin, bursa-like pouch that surrounds the ovary

-helps orient the infundibulum

Function of Mesosalpinx

ensures the egg makes it into the oviduct

-does this by surrounding ovary and orienting the infundibulum

Mesometrium

supports the uterine horns

-largest portion

-continuous with the dorsal peritoneum

Ovary

analogous to the male testicle

-location of follicle maturation and ova release

Hormones of the Ovary

-estrogen

-progesterone

-oxytocin

-relaxin

-inhibin

-activin

Estrogen Release

caused by follicle growth

-released by follicle

Function of Estrogen

-effects on CNS (feminine behavior)

-increased mass of the uterus (increased density, pregnancy prep)

-increase contractibility of the uterus (increased muscularity)

-development of secondary sex characteristics (feminine appearance and fat deposition)

-growth of the mammary gland ducts

-stimulates or inhibits GnRH and LH

GnRH

gonadotropin releasing hormone

LH

luteinizing hormone

Progesterone

hormone of pregnancy

-released by the corpus luteum

Functions of Progesterone

-prepares the uterus for implantation and pregnancy (increased mass for implantation and protection)

-acts with estrogen to induce behavioral patterns of estrus

-develops alveoli of mammary gland

-inhibits the rise of LH that causes ovulation by inhibiting GnRH and LH release

Oxytocin

triggers contraction of smooth muscle (partuition)

Relaxin

triggers cervical dilation and softens pelvic ligaments

-initiates widening of birth canal during partuition

Inhibin

inhibits secretion of FSH, without affecting LH secretion

-stops follicular development

Activin

stimulates FSH secretion

Follicle Devlopment in the Ovary

-primary

-secondary

-tertiary (Graafian)

-ova

-corpus hemmoragicum

-corpus luteum

-corpus albicans

Layers of the Ovary

-surface epithelium

-tunic albuginea

-cortex

-medulla

Ovary of the Mare

- cortex on the inside of the ovary, medulla on the outside

- ovulation fossa

- follicle cannot be felt

In which of the following species can a follicle NOT be palpated?

horses

Ovulation Fossa

the sole location of ovulation in the ovary of the mare

Primordial Follicles

-microscopic (smallest form)

-immature

-number varies

Females are born with all of their follicles in which follicular stage?

Primordial follicles and Primary Follicles

Primary Follicle

-slightly more developed than primordial follicle

-can develop or degenerate

Secondary Follicle

2 or more layers of follicle cells

-surrounded by Zona pellucida

Zona pellucida

a thick translucent layer present on secondary and tertiary follicles

Antral Follicle

-also called tertiary follicle

-has a fluid filled cavity (antrum)

-may become dominant pre-ovulatory follicle

Graafian Follicle

dominant pre-ovulatory follicle

Layers of the Tertiary Follicle

Theca externa, theca interna, granulosa

Theca externa

supports follicle

Theca interna

produces androgens

Granulosal Layer

has FSH receptors

-innermost level of the antral follicle

Ovulation

1. dominant antral follicle ruptures

2. follicle collapses into corpus hemorrhagicum

3. Corpus luteum forms and maintains pregnancy

Way to Remember Ovulation

1. Follicle ruptures (pimple pops)

2. Follicle collapses (wound from pimple)

3. Corpus Luteum (somewhat healed pimple)

Functions of the Oviduct

-catch ova

-site of fertilization

-early development (prior to uterine horns or uterus)

Sections of the Oviduct

infundibulum, ampulla, isthmus

Infundibulum

opens and surrounds ovary during ovulation

-terminal end of oviduct

-funnel shaped opening

-captures oocyte

Ampulla

occupies half or more of oviduct

-large diameter with mucosal folds

-site of fertilization

Isthmus

-where newly formed zygote resides before entering uterus

-smaller in diameter (thicker muscular wall)

- moves sperm and ova (in opposite directions) into the ampulla

Uterotubal Junction

connection site of isthmus and uterus

Functions of Uterotubal Junction

-movement of embryo to uterus (cows)

-reduces polyspermy in sows

Polyspermy

fertilization by multiple sperm

-causes early loss

What hormone forms a kink in the uterotubal junction in cows?

estradiol

Uterus

organ of pregnancy

-many types

Duplex Uterus

-2 uterine horns

-2 cervixes

-1 vagina

Examples of species with a duplex uterus?

rabbit, mouse

Advanced Duplex Uterus

-2 uterine horns

-2 cervixes

-2 vaginas

Bicournate Uterus

-2 long uterine horns

-common uterine body

-1 cervix and 1 vagina

What species has an advanced duplex uterus?

opposum

What species has a bicournate uterus?

Pigs

Bipartite Uterus

-2 smaller uterine horns

-common uterine body

- 1 cervix and 1 vagina

Examples of species with bipartite uterus

cow, ewe, doe

Modified Bipartite Uterus

-2 smaller uterine horns

-larger uterine body

-1 cervix and 1 vagina

What species has a modified bipartite uterus?

Mare

Simplex Uterus

-no uterine horns

-all uterine body

-1 cervix and 1 vagina

Perimetrium

thin outer layer of the uterus

-serosa

Myometrium

muscularis

-middle layer of the uterus

-hormone roles

Endometrium

mucosal and submucosal layers of the uterus

-embryo development

-uterine glands change

In which species does menstruation occurs?

humans

prostaglandin F2 alpha

causes luteolysis if the animal is not pregnant

Placental folds

structure in non-ruminants

-placental scars

Main Function of Uterus

-sperm transport

-control cyclicity

-environment for pre attached embryo

-expulsion of the fetus and fetal placenta

Caruncles

small non-glandular area of the endometrium that is highly vascularized

-maternal portion of placenta for ruminants

-endometrial folds

-surface for placenta development

Cotyledons

fetal portion of the placenta

Placentome

a cotyledon and caruncle together

Convex Placentome

cow

Concave Placentome

ewe

Diffuse Placentome

mare and sow

Parts of Placentome

chorion, carnucle, endometrium

Cervix

thick wall that is a barrier to sperm and offers protection during pregnancy because of the presence of a thick mucus plug.

Structure of Cervix

single or multiple folds/rings

-cervical canal

-cow/ewe produce mucous during estrus

Function of the Cervix

Protects uterus

Vagina

organ of copulation

-mucosal epithelial tissue

Which species have a fornix vagina?

cow, ewe, mare

Cranial Vagina

high degree of secretory activity

-columnar epithelium secretion high at peak estrogen

-stratified squamous epithelium thickens at peak estrogen

Vestibule

the urinary and reproductive tract

Gartner's Duct

fluid outlet for embryo

suburethral diverticulum

a blind pouch of unknown function, causes issues with urinary catheter

What species have a suburethral diverticulum?

cow and sow

Vulva

external portion of the reproductive tract

Portions of the vulva

labia major and labia minor

Function of Vulva

minimizes the entrance of foreign material into the vagina

Perenium

surrounds vulva and anus

Clitoral fossa

houses the clitoris

Clitoris

analogous to male penis, composed of erectile tissue and covered with stratified squamous tissue, that has many sensory nerve endings

Vestibular glands

secrete mucous like material during estrus

Woffian Duct

embryonic remnant

left

Most birds only have a functional _____ ovary.