Repro exam 1 Flashcards
In general, where are the ovaries located? Be specific
Variable due to species and pregnancy
Generally caudal to kidneys and close to tips of uterine horns
What are the 2 major functions of the ovaries?
Produce ova
Produce sex hormones
Extension of peritoneum that suspends the ovaries, uterine tubes, and uterus
Broad ligament
What are the 3 ligaments that suspend the ovary in the abdomen?
Mesovarium
Suspensory ligament
Proper ligament
Be able to state where the ovarian ligaments are located
Mesovarium: suspends ovaries from the abdominal wall below and to either side of the lumbar vertebrae
Proper ligament: runs from caudal pole of ovary to tip of adjacent uterine horn
Suspensory ligament: attaches ovary to the last 1 or 2 ribs
In which of the ovarian ligaments are found the ovarian artery and vein?
Mesovarium
Which of the ovarian ligaments must a surgeon typically stretch and break when performing an ovariohysterectomy in a dog or cat?
Mesovarium and suspensory ligament
What is significant about the ovarian bursa?
Sac-like cavity that can be surrounded by fat, making it hard to see the actual ovary
In what species is an ovarian bursa found?
Canine & feline
What species is an ovulation fossa found?
Equine
What is significant about an ovulation fossa?
Specialized structure where ovum leaves ovary during ovulation
Other species: ovum leaves ovary from random location
How do sow ovaries differ from other mammals?
They are lobulated
In what region of the ovary are the germinal epithelium cells and follicles located?
Cortex (outer portion)
Transient structure formed from cells lining ruptured follicles
Releases hormones
Corpus luteum
What function(s) does the uterine tube serve?
Captures ovum released during ovulation
Moves sperm from uterus toward ovum
Where does fertilization of the ovum typically occur?
Uterine tube
Proximal portion of the uterine tube, closest to the ovary
Covers ovary and catches ovum during ovulation
Infundibulum
Explain how an abdominal pregnancy could occur
Ovum could slip out in the space between the ovary and uterine tube into the abdomen
If fertilized in the abdomen, an abdominal pregnancy can occur
Fringe-like margin of the infundibulum
Creates current to sweep ovum into uterine tube
Fimbria
Portion of the broad ligament that suspends the uterine tube
Mesosalpinx
Describe the basic anatomy of the uterus
Uterine tubes empty into the horns of the uterus
Horns continue causally to form the body
Ligament that joins the caudal parts of the horns in the cow, causing the body to appear larger than it really is
Intercornual ligament
Non-glandular mushroom like projections from the inner surface of the ruminant uteri where fetal membranes attach
Caruncles
Why are caruncles significant?
Fetal membranes attach at these sites in ruminants
Muscle of the uterus
Myometrium
Portion of the broad ligament suspending the uterus
Mesometrium
Where is the cervix located?
Between the uterus and vagina
What determines if the cervix is opened or closed?
Hormonal status
Closed except during estrus (heat) and parturition
The cervix produces mucus, which at times can be thin, watery, and slippery, while at other times it can be thick & sticky. What causes the consistency to change?
Hormonal changes during the estrous cycle
What is the purpose of the mucus produced by the cervix?
Thin and slippery: acts as lubricant
Thick & sticky: plugs opening to cervical canal
In what species are annular folds found?
Bovine
What is the significance of annular folds?
Inner lining of cow’s cervix arranged in series of circular rings, causing canal to have an almost spiral course
What does copulation mean
Act of breeding
What does parturition mean
Act of giving birth
What are the 2 major types of epithelial cells found in the vagina?
Stratified squamous
Stratified columnar
Area surrounding the projection of the cervix into the vagina
Fornix
What is significant about the fornix?
Fold of dorsal vaginal wall may hang over cervix, obscuring its opening
Portion of the Repro tract between the vagina and vulva
Has Repro and urinary functions
Vaginal vestibule
Blind pouch below urethral orifice in cows
Suburethral diverticulum
What is the significance about the vagina vestibule and Suburethral diverticulum?
Can mistake this area for the vagina during artificial insemination
Transverse fold of tissue that lies over the urethral orifice
Hymen
The top and bottom junction of the labia are known as
Commissures: dorsal and ventral
Located just within the ventral commissure
Same embryologic origin as penis
Clitoris
How is the clitoris similar to the penis?
2 crura, body, glans
Erectile tissue covered by stratified squamous epithelium
Rich in sensory nerve endings
Where is the perineum found?
Tissues between the anus and vulva
What is significant about the perineum?
Occasionally site of herniation of abdominal contents
Immediately deep to skin
Fibroelastic tissue mixed with smooth muscle cells
Passes between testes to contribute to formation of scrotal septum
Contracts in response to cold temps to hold testicles closer to body
Tunica dartos
What happens to spermatogenesis as the temp increases?
If temp rises above 80F, semen quality begins to decrease
When ambient temp >100F, scrotal cooling mechanism cannot keep testicle below normal body temp = spermatogenesis stops
What are the 2 major functions of the testicle?
Spermatogenesis
Production of testosterone
What occurs in the seminiferous tubules?
Spermatogenesis
These cells secrete testosterone
Located in the connective tissue between the seminiferous tubules
Interstitial cells of leydig
Closely adhered to testicle
Heavy fibrous capsule
Tunica albuginea
Tissue adhered to the tunica albuginea
Visceral vaginal tunic
Tissue between the areolar tissue and visceral vaginal tunic
Continuous with it
Parietal vaginal tunic
What type of castration?
Tunics incised
Testicular vessel, ductus deferens, and cremaster muscle are ligated directly or individually
Open castration
What type of castration?
Tunics not incised
Testicular vessels, ductus deferens, and cremaster muscle all ligated together in the spermatic cord
Closed castration
What are the advantages if a closed castration?
Reduced risk of hemorrhage from vaginal tunics
Rapid & routine techniques
Body cavity not opened: infection unlikely, decreased likelihood of seeding peritoneal cavity with neoplastic cells
What are the disadvantages of a closed castration?
Cannot pull spermatic cord as far out of the body during clamping/ligation process
Ligatures can be indirectly placed on testicular artery and vein
What occurs in the epididymis?
Spermatozoa maturation
What is the gubernaculum testis?
Band of connective tissue
What is the significance of the gubernaculum testis as it relates to the location of the testicles in the body?
Connects the tail of the epididymis to the scrotum
What structures make up the spermatic cord?
Cremaster muscle, ductus deferens, testicular vessels and nerves
This controls the location of the scrotum with regard to distance from the rest of the body
Cremaster muscle
Where is the inguinal ring found?
Space between the external and internal inguinal rings
Passage from abdominal cavity into the scrotum
What can happen if the inguinal canal is too large?
Inguinal hernia: loop of bowel can enter the scrotum
Are inguinal canals found only in males?
Yes
Where do testes originate in the embryo?
Just caudal to the kidneys
What does the term cryptorchid mean?
Hidden testes
Testicle fails to descend
In general, are bilateral cryptorchid males fertile?
No, usually sterile
Doe cryptorchidism affect the production of the male sex hormone?
No, production of testosterone is unaffected
In what species is cryptorchidism a dominant trait?
Stallion and boar
A cryptorchid testicle has a higher chance of developing…
Neoplasia (cancer)
The proper word for the material that leaves the male during copulation is….
Ejaculate
Part of the ductus deferens
Glandular enlargement in the terminal ductus deferens
Contributes fluid to semen
Ampullae
In what species is the ampullae found?
Well developed in: equine, bovine, ovine
Small in canine
Paired glands that empty along with the ductus deferens into the pelvis urethra
Vesicular glands/seminal vesicles
What species lack seminal vesicles?
Canine
About what percentage does the seminal vesicles contribute to the total volume of the discharge from the male?
70%
What is the purpose of fructose in the fluid contributed by the seminal vesicles?
Provides energy to the spermatozoa to power their movement in the female repro tract
Describe the appearance of the prostate gland in the dog
Unpaired, discrete, walnut shaped
What purpose does the fluid produced by the prostate appear to serve?
It has basic pH which appears to neutralize the acidic environment of the vagina
What are the symptoms of prostatic hypertrophy?
Gland swells as dog ages
Can occlude urethra, making urination difficult
Can press against the rectum, causing constipation like symptoms
Also susceptible to infection and neoplasia
What happens to the prostate gland if testosterone levels are reduced?
Atrophy
Small, paired glands caudal to the other accessory sex glands
Not present in dogs
Bulbourethral glands
What is the purpose of the product of the bulbourethral gland?
Produces clear, viscous fluid that flushes residual urine from urethra and lubricates urethra for passage of spermatozoa
Describe the basic process by which an erection occurs
Erection occurs when more blood enters the penis by way of the arterial supply than leaves through the veins
Increase in blood volume enlarges the penis and makes it turgid
Controlled by hormonal and nervous input
What is the sigmoid flexure?
S-shaped curve of the corpora penis
What species have a sigmoid flexure?
Bull, ram, boar
Bone in penis of canine that partially surrounds the urethra
Allows intromission before full erection occurs
Os penis
Describe some ways the os penis can cause difficulties for the male dog
Urethral stones may become lodged in this part of the urethra
What does intromission mean?
Inserting the penis into the vagina in sexual intercourse
Free extremity of the penis
Glandis penis
Free portion of the urethra that projects beyond the glans
Urethral process
In what species is the urethral process present?
Stallions and rams
In what species are epithelial spines found on the penis?
Felines
What is the purpose of the epithelial spines?
Stimulate female to ovulate
What species has a bulbis glandis?
Canines
What purpose does the bulbis glandis appear to serve?
Ties dogs together after mating
Seems to help with impregnating the bitch
What happens if the bulbis glandis becomes filled with blood prior to intromission?
Penis will not fit into vagina
Invaginate fold of skin surrounding the glans
Prepuce
When penis is unable to retract back into the prepuce
Paraphimosis
In what specific structure in the testicle does spermatogenesis take place?
Seminiferous tubules
Cells which will eventually produce spermatozoa or ova
Germinal epithelium
Diploid cells near periphery of the seminiferous tubules
Spermatogonium
Are primary spermatocytes diploid or haploid?
Diploid
Are secondary spermatocytes diploid or haploid?
Haploid
How many spermatogenesis result from each spermatogonium?
4, each is haploid
Where do spermatozoa become motile?
Epididymis
Where do spermatozoa complete the maturation process?
Female repro tract
This hormone released from the hypothalamus
Stimulates pituitary gland to produce and secrete increased amounts of FSH and LH
Gonadotropin releasing hormone, GnRH
Hormone secreted by anterior pituitary gland
Stimulates mammary production and synthesis of milk
Prolactin
Hormone secreted by the posterior pituitary gland
Stimulates uterine contractions and milk letdown
Oxytocin
Hormone released from pituitary gland
In female: causes follicles in ovary to develop and enlarge
In males: stimulates spermatogenesis along with testosterone and LH
Follicle stimulating hormone, FSH
FSH production is inhibited by what 2 hormones that are secreted by follicles in females
Estrogen and inhibin
Estrogen stimulates production of this hormone
Luteinizing hormone, LH
This hormone causes final maturation of follicle, ovulation, and formation of corpus luteum from remaining follicular tissue after release of the oocyte
Released from pituitary gland
Luteinizing hormone, LH
These 2 species are induced ovulators
Queen and rabbit (doe)
In males, LH is sometimes called this
Stimulates leydig cells to produce testosterone
Interstitial cell stimulating hormone, ICSH
A group of steroid hormones with similar physiologic activity
Produced by follicles and placenta
Estradiol is most important one
Estrogen
Estrogen causes what type of feedback on FSH
Negative
Estrogen causes what type of feedback on LH
Positive
This hormone causes female sexual behavior
Estrogen
Hormone secreted by follicles
Inhibits FSH secretion
Inhibin
A group of steroid hormones with similar physiologic activity
Progesterone is most important
Progestins
Hormone produced by mature corpus luteum on ovary and by placenta
Has negative feedback on LH
Maintains pregnancy
In most species, causes female to reject male
Progesterone
False pregnancy
Pseudocyesis
Uterus filled with pus, usually in older dogs
Pyometra
Group of hormone-like lipids
Released from cells throughout the body
Prostaglandins
This prostaglandin is produced by endometrium of non-pregnant uterus
May be stimulated by estrogen
Blocked by pregnancy
PGF 2alpha
Levels of this hormone decline after ovulation
Removes the negative feedback suppression of FSH production
Estrogen
Rising levels of FSH cause new wave of what?
Occurs even while corpus luteum from previous ovulation is still functional
Follicular development
PGF 2alpha levels rise in response to what type of estrogen levels
This causes luteolysis
Rising estrogen levels
Progesterone levels …… With destruction of corpus luteum
This removes the negative feedback suppression of LH
Fall
LH levels rise rapidly due to low progesterone levels. This is called what?
LH surge
Follicles complete maturation and ovulation occurs when this hormone surges
LH
These 2 groups of hormones are secreted by the uterus and placenta as well as ovary during pregnancy
Estrogens and progestins
Oogenesis results in how many oocytes?
1
Oogenesis results in how many polar bodies?
3
