animal repro exam 1

Folliculogenesis

The development of follicles from their initial stage as a primordial follicle through their final stage as a Graafian follicle and ovulation.

Primordial follicles

Follicles of the ovary present at birth and decrease in number as the female matures.

Primary follicles

Follicles of the ovary that remain at this stage until puberty. Most never ovulate and undergo atresia.

Secondary Follicles

Follicles of the ovary with an increase in granulosa cell layers and formation of the zona pellucida, theca interna, and theca externa.

Tertiary Follicles

Maturing follicles of the ovary with antrum formation (fluid-filled space containing liquor folliculi).

Graafian Follicle

Similar structures as tertiary follicle; Layers & fluid increase -large, blister-like structure forms on surface of ovary. Capable of ovulation, dependent on LH surge

Antrum (liquor folliculi)

Large fluid filled space in tertiary follicle

Luteogenesis

The formation of a corpus luteum.

Luteolysis

The regression of a corpus luteum.

Corpus hemorrhagicum (CH)

Newly ruptured follicle; essentially a blood clot.

Corpus luteum (CL)

Yellow structure; temporary endocrine gland, produces progesterone.

Corpus albicans (CA)

Remains after CL regresses.

Cystic follicles

Failure of a Graafian follicle to ovulate; persists on the ovary and continues to grow, producing high amounts of estradiol and can cause the animal to show a continued estrus behavior

Luteal Cysts

Occur when theca interna cells do not fill the cavity that is created upon ovulation (the rupturing of the follicle). They can cause abnormal estrous cycles and early embryonic mortality.

Persistent Corpus Luteum

The failure of the CL to regress. It causes a suppression of the estrous cycle due its resemblance to pregnancy (i.e., progesterone is still produced and the body falsely identifies this state as a pregnancy).

Endometrium

The inner lining of the uterus, consisting of the mucosa and submucosa.

Myometrium

The muscular layer of the uterus.

Perimetrium

The outer serosal layer of the uterus.

Broad Ligament

Supports and suspends the reproductive tract, provides vascular supply, lymphatic drainage, and nerves.

Mesometrium

Part of the broad ligament, supports the body.

Mesosalpinx

Part of the broad ligament, supports the oviduct.

Mesovarium

Part of the broad ligament, supports the ovary.

Ovaries

Female gonads responsible for producing female gametes (ova) and hormones (estrogen and progesterone).

Cortex

Outer zone of the ovary.

Medulla

Inner zone of the ovary.

Oviduct

The structure that carries the ovum from the ovary to the uterine horn; site of fertilization and early embryo development.

Oviduct Functions

Transports the ovum, sperm storage and capacititation, fertilization, and early embryo development

Infundibulum

The segment of the oviduct closest to the ovary, characterized by a funnel-like opening.

Ampulla

The segment of the oviduct between the infundibulum and the isthmus; site of fertilization.

Isthmus

The segment of the oviduct connecting the ampulla to the uterine horn.

Ampullary-Isthmic Junction (AIJ)

The junction between the ampulla and the isthmus of the oviduct.

Uterotubal Junction (UTJ)

The junction between the oviduct and the uterine horn.

Uterus

Organ between the oviducts and the cervix. Functions include sperm transport, luteolysis, control of cyclicity, embryo environment, maternal placenta, and expulsion of the fetus.

Bicornuate Uteri

Uteri consisting of a body and two horns (cornua); found in cows, ewes, sows and mares.

Simplex Uteri

Uterus with no horns, as found in humans.

Cervix

Located between the vagina and uterus; functions include lubrication, flushing, and acting as a barrier.

Cervix (Cow & Ewe)

Annular rings in the cervix of cows and ewes.

Cervix (Sow)

Corkscrew shape in the cervix of sows

Cervix (Mare)

Longitudinal folds in the cervix of mares.

Vagina

Connects the cervix to the external genitalia and serves as the female copulatory organ.

Vulva

External tissue of the female reproductive tract; receives the penis during copulation.