Exam 1 Flashcards
What are the structures of the repro tract?
Ovaries, oviduct, uterus, cervix, vagina, and external genitalia
Where is the female repro. tract located? Why is this important in livestock species?
Directly beneath rectum in livestock species.
Allows for manual/ultrasonic palpation of tract in cattle and horses
What can palpation be utilized to do?
- Diagnose ovarian status
- Diagnose pregnancy
- Manipulate tract for artificial insemination (A.I)
- Recover embryos using nonsurgical techniques
- Identify abnormalities in tract
What are the 4 different layers of the female tract?
- Serosa (outer)
- Muscularis
- Submucosa
- Mucosa (inner)
What are the two layers of the muscularis?
Inner –> circular muscle
Outer –> longitudinal muscle
What are the functions of the muscularis?
Produce muscle contractions for:
- transport of secretory products, gametes, and early embryos
- Expulsion of fetus and placenta
What is the submucosa made of and its function?
Blood vessels, nerves, and lymphatics
Support layer for the mucosa
What is the serosa?
Outer single layer of squamous (flattened) cells
What is the mucosa and its function?
Epithelium –> secretory layer
- Surrounds lumen (interior) of repro. tract
- Each portion of repro. tract has different type of mucosa depending on the function of that portion of the tract
What is the broad ligament and its function?
Double layered connective tissue sheet
Supports and suspends ovaries, oviduct, uterus, cervix, and anterior vagina
What are the three components of the broad ligament?
- Mesovarium
- Mesosalpinx
- Mesometrium
What is the mesovarium made up of?
Blood and lymphatic vessels and nerves for the ovary
What is the function of the mesovarium?
- Forms hilus of the ovary
- Another ovarian supportive ligament –> utero-overian ligament
- Attaches ovary to uterus
What is the mesosalpinx?
- Surrounds and supports oviduct
- Thin, serous portion of the broad ligament
- Bursa-like pouch that surrounds the ovary
What is the function of the mesosalpinx?
Helps orient the infundibulum of oviduct, so ova released at ovulation is directed into oviduct
–> “catchers mit”
What is the mesometrium?
Largest portion of broad ligament
What is the function of the mesometrium?
- Supports the uterine horns and uterine body
- Hangs from dorsal wall
What is the ovary structure?
Round, knot-like structure
What are the functions of the ovary?
- Produce female gametes (ova)
- Produce the hormones estradiol and progesterone
- Product hormones –> oxytocin, relaxin, inhibin, activin
What are the anatomical portions of the ovary?
Tunica albuginea
Ovarian cortex
Ovarian medulla
What is the tunica albuginea?
- Outer, connective tissue surface
- Single layer of cuboidal cells –> germinal epithelium
What is the ovarian cortex?
- Beneath tunica albuginea
- Contains population of oocytes, which will develop into mature follicles and eventually ovulate (except in mare)
What does the ovarian cortex contain?
- Follicles
- Corpus luteum
- Corpus albicans
What is the corpus luteum?
(Pleural = corpora lutea) or CL
“Yellow bodies” –> large structures
Produce progesterone
What is the corpus albicans?
(Pleural = corpora albicantia) albicans = albino, therefore, "white bodies"
Smaller structures –> represent scar tissue - degenerate form of CL
What is the ovarian medulla?
Central portion of ovary
What does the ovarian medulla contain?
- Vasculature
- Nerves
- Lymphatic system
What is folliculogenesis?
Development of immature follicles into mature follicles to become candidates for ovulation?
What are the four types of follicles present within the ovary?
- Primordial
- Primary
- Secondary
- Antral (tertiary)
What is a primordial follicle?
Smallest, most immature, microscopic ova within follicle
Has 1 layer of squamous (flattened) cells
What is a primary follicle made of?
1 layer of cuboidal (cube-like) epithelium or follicle cells
What is a secondary follicle made of?
2+ layers of follicle cells
Ova contain a thick, translucent layer - zona pellucida
What is an antral follicle?
Presence of antrum – fluid-filled cavity
- Filled with follicular fluid
- When dominant preovulatory follicle, termed Graafian follicle
What are the three layers of antral follicles?
- Theca externa
- Theca interna
- Granulosa cell layer
What is the theca externa?
- Loose connective tissue
- Surrounds and supports oocyte
What do theca interna cells produce?
Cells produce androgens
What is the granulosa cell layer and what is its function?
- Separated from theca interna by thin, basement membrane
- Produce estrogen, inhibin, and follicular fluid
Aids in maturation of oocyte
What happens to follicle upon ovulation of antral follicles?
Form corpus hemmorrhagicum
“Bloody body”
What are the characteristics of corpus hemorrhagicum?
- Rupture of small vessels cause hemorrhage
- Loss of antral fluid causes follicle to collapse into numerous folds
What forms the corpus luteum?
Theca interna and granulosal cells differentiate into luteal cells to form the corpus luteum
What are the three sections of the oviduct?
- Infundibulum
- Ampulla
- Isthmus
What is the infundibulum?
- Ovarian end, funnel-shaped opening
- “Captures” newly-ovulated oocyte
- Surface has many velvety, finger-like projections –> fimbrae
What are the functions of fimbriae?
- Increased surface area
- Cause infundibulum to slip over entire surface of ovary at ovulation
What is the ampulla?
- Thick portion, occupies 1/2 or more of the oviduct
- Large diameter
- Internal structure has many fern-like mucosal folds with ciliated epithelium
What is significant about the ampulla?
- Site of fertilization
- Merges with isthmus at ampullary-isthmic junction (AIJ) - sphincter –> only allows fertilized oocytes by in mare
What is the isthmus?
- Smaller in diameter than ampulla
- Thicker muscular wall, fewer mucosal folds
- Connected to uterus by uterotubal junction (UTJ)
What is the is important about the UTJ?
- Regulates movement of embryo into uterus
- Can act as a barrier to polyspermy (swine)
How does the UTJ act under increased / decreased estradiol concentration?
With increased estradiol, acts as a “kink” which blocks embryo movement into uterus.
Decreases estradiol allows entry into the uterus.
What is the function of oviductal smooth muscle layer (muscularis)?
Transportation of oocytes and sperm to site of fertilization
What are the functions of the oviductal mucosa?
- Provide optimum environment for unfertilized oocyte
- Sustain sperm function until oocyte arrives
- Provide suitable environment for early embryo
What is the uterus?
Connects oviducts to cervix –> two uterine horns (cornua)
What are the five primary functions of the uterus?
- Sperm transport
- Luteolysis and control of cyclicity
- Environment for pre-attachment embryo
- Maternal contribution to placenta
- Expulsion of fetus and fetal placenta
What are the three types of uteri?
- Duplex
- Bicornuate
- Simplex
What is a duplex uterus?
2 cervical canals –> each uterine horn is distinct
What are the two types of duplex uterus and what species have them?
- Single vaginal canal –> mouse, rabbit
- Double vaginal canal –> marsupials and opossum
What is a bicornuate uterus and what species have them?
- 2 uterine horns and small uterine body
- Length of horns dependent upon amount of fusion of paramesonephric ducts in developing embryo
- Single vaginal and cervical canals
- Internal and external uterine bifurcation
Examples –> horse, cow, pig
What is a simplex uterus and what species have them?
- SIngle uterine body, no uterine horns
- Nearly complete fusion of paramesonephric ducts
Example –> primate, human
What are the three layers of the uterus?
- Perimetrium
- Myometrium
- Endometrium
What is the perimetrium?
- Serosa –> part of the peritoneum
- Thin, nearly transparent
What is the myometrium?
Muscularis –> directly beneath perimetrium
What is the longitudinal smooth muscle of the myometrium?
- Small ridges running anterior to posterior
- Outer portion
What is the circular smooth muscle of the myometrium?
- Wrap around uterus in circular manner
- Inner portion
What are the functions of the myometrium?
- Provide contractility of the uterus
- Muscular ‘tone’
- Expulsion of fetus and fetal membranes
What is muscular tone of myometrium with high estrogen / low progesterone?
Turgid –> much “tone”
What is muscular tone of myometrium with high progesterone / low estrogen? What is this phase associated with?
Soft, flaccid –> very little ‘tone’
Associated with sperm transport and uterine production of mucus-like material
What is the endometrium and its function?
Mucosa + submucosa –> inner portion
Secrete nutrients into lumen for developing embryo and sperm via endometrial glands
Where are endometrial glands?
Protrude from mucosa into submucosa
What do endometrial glands do under estrogen control?
- Coil under estrogen control
What do endometrial glands do under estrogen control?
- Full secretory potential under progesterone influence
What species have sloughed and not sloughed endometrial glands?
- Sloughed –> primate, human
- Not sloughed –> lower animals
What hormone do endometrial glands produce?
Produce prostaglandin F2α
What does Prostaglandin F2α do?
- If oocyte not fertilized during estrous cycle … Lyses the CL to induce another estrous cycle
What about ruminant endometrial glands is unique?
Ruminants have small, non-glandular regions – caruncles – give rise to maternal portion of placenta
What is the cervix? How does it act in ewe and cow species?
Thick-walled, non-compliant – acts as sperm barrier in ewe and cow
What are the three function of the cervix?
- Provide lubrication
- Act as a flushing system
- Act as a barrier during pregnancy
What is the cervix composed of?
Composed of cervical canal with folds or rings protruding into canal
What is cow cervix like? Where is sperm deposited?
Several rings from interlocking finger-like projections
- Sperm deposited in vagina
What is a pig cervix like? Where is sperm deposited?
Rings interdigitate in specific manner – accepts corkscrew penis of board
- Sperm deposition in cervix
What does the cervix produce? How does it differ between species?
Produces mucous during estrous in cow and ewe – much less in sow and mare
What is the function of cervical mucus?
- Lubricated vagina during copulation
- Flush out foreign materials
- Prevents microorganisms from entering uterus
How does mucus change throughout estrous cycle where there is high progesterone?
Properties change with stage of estrous cycle
- During pregnancy – high progesterone – very viscous. Provides “plug” to isolate fetus from external enviroment
What is it called when there is lots of cervical mucous? What happens when this is removed?
Cervical seal of pregnancy
Remove –> abortion
What is the vagina?
Copulatory organ and site for expulsion of urine
What is the vaginal tissue like?
Poorly defined muscular layer, well developed mucosal epithelium
What is mucosal epithelium like near the cervix?
Much secretory activity
–> columnar and ciliated columnar epithelium
What is the fornix vagina?
In cow and mare, cervix protrudes into the vagina forming large crypt around cervix –> fornix vagina
Large amounts of mucous present here during estrus –> sperm deposition occurs here in the cow!
What species does not have fornix vagina?
Not present in the sow!
What is tissue like in posterior vagina?
Stratified squamous epithelium
Changes with stage of estrous cycle
What happens to posterior vagina at high estrogen levels during estrus?
Dramatic thickening
What is the posterior vagina made up of?
Vestibule –> belongs to urinary and genital systems
Where does the posterior vagina extend to?
Extends from external urethral orifice –> labia of vulva
What are vestibular glands and what is its function?
Submucosa of vestibule
Secretes mucus-like substance during estrous
What is the vulva?
External portion of the female repro. tract
What does the vulva contain?
Contains labia majora and labia minora
What is the function of the vulva?
- Labias meet to form commissure (site of union)
- Minimizes enterance of foreign material
What is the labia?
Skin –> contains sweat glands and hair follicles
What does the labia consist of?
Consist of adipose tissue with smooth muscle bundles –> constrictor of vulvae muscles
Where is the clitoris housed?
Housed in ventral commissure of vestibule –> same as glans penis in male
What kind of tissue is the clitoris made of?
Erectile tissue –> stratified squamous epithelium
What does the clitoris contain?
Many nerve endings?
What happens to clitoris at high estrogen levels?
Erection of the clitoris
What happens when there is stimulation of the clitoris?
Increased conception rates by A.I.
What are the overall functions for the female reproductive tract?
- Control activity of organs (hormonal)
- Transport sperm
- Produce oocyte
- Facilitate fertilization
- Provide environment for embryo and fetus
- Give birth to fetus
- Recycle to become pregnant again
- Provide nutrients to young
What are the four layers of the ovary from outside to inside?
- Germinal epithelium
- Tunica albuginea
- Cortex
- Medulla
What does the ovary cortex contain?
Contains female germ cells
Oocytes –> mature oogonia
Follicles
Corpa lutea/ luteum
What is unique about the mare ovary?
Mare has inversion of cortex and medulla
Where can ovulation occur for cow, ewe, and sow ovary?
Ovulation can occur at any point
Where does ovulation occur for the mare?
The mare ovary has an inversion of the cortex and medulla (outside layer). Therefore, ovulation can only occur at the ovulation fossa
What are the ovarian functions?
- Produce estrogens
- Contains oocyte
- Produce progesterone
Diagram of Ovary
