Female repro - general/ovaries Flashcards
what initiate pathways of ovarian differentiation and development in early embryo
genes –> dax1 (promotes ovarian development, inhibits testicular development)
development of accessory genitalia in early embryo
gonad dependent –> all sexual development would be female if not prevented by testicular hormones
how an animal is classified as hermaphrodite
internal genitalia and gonads of both sexes –> one ovary and one testis, two ovo-testes
what makes an animal a pseudohermaphrodite (features)
- both gonads are either ovary or testes
- classified based on gonad type
- accessory organs modified to opposite sex
- common in pigs (hereditary)
what is a freemartin
- bovine –> female heifer calf born twin with bull calf
- sterile
etiology of freemartin
- fusion of placental vessels –> shared circulation (transfer of hematopoietic cells between fetuses)
- gene products from cells of male fetus induce sertoli cells and seminiferous cordlike structures in ovaries of female twin
- both x and y chromosomes are present in cells of freemartin (lymohocytes and RBC)
gross features of freemartin
- gonad thin cord-like structure
- epididymis absent
- tubular genitalia ranges from cord to well-developed uterine horn
- no communication of uterus to vulva
- vestigial seminal vesicles present
- hypoplastic vagina, vestibule, vulva
diagnosis of freemartinism
- blood test (karyotype of lymphocytes for XY chromosomes)
- vaginal length measurement
spontaneous ovarian hemorrhage
spontaneous rupture of follicles causes mild hemorrhage that sometimes produces adhesions (can be severe in mares)
iatrogenic ovarian hemorrhage
manual expression of CL by means of rectal palpation (bleeding may be severe causing death)
parovarian cysts and cystic rete
- cystic structures located around ocaries
- remnants of persistent wolffian ducts (mesonephric ducts)
what are anovulatory follicular cysts (intra-ovarian)
- large fluid-filled cysts on ovaries
- failure of mature follicle to ovulate
- occurs postapartum in heavy producing mature dairy cows in winter months
- unknown etiology
pathogenesis of anovulatory follicular cysts
pituitary gonadotropins not released in early estrus as normal –> mature follicle not exposed to ovulating/lutenizing action of LH –> no ovulation of lutenization
functionality of anovulatory follicular cysts
- some functional
- estrogen produced –> prolonged estrogenism
- cow in constant heat –> nymphomania
- majority are anestrus
gross appearance of anovulatory follicular cysts
- ovary: large thin walled, fluid-filled cyst 1”+ in diameter, ovum absent, single or multiple, one or both ovaries
- vulva: enlarged and edematous, increased mucus, mounting (constant heat)
what are lutenized cysts
- insufficient or delayed release of LH during estrus
- ovulation does not occur –> theca undergoes partial lutenization
gross appearance of lutenized cysts
- fluid-filled cyst with luteal tissue around periphery
- lack ovulation papilla
- distinguished from cystic CL, which have ovulation papilla –> elliptical in cross section
functionality of lutenized cysts
- some are functional and produce progesterone over extended length of time
- keep cow from normal cycling (anestrus)
- initiates secretory endometrium (can lead to pyometra in cow)
changes in other organs due to functional follicular cysts
- all related to prolonged estrogenism
- uterus (atonic, enlarged, doughy, cystic hyperplasia of endometrium)
- cervix (excessive mucus)
- vagina (edematous)
swine cystic ovaries
- common cause of infertility
- multiple, sometimes large follicular cysts
- irregular estrus cycles
- high incidence when progesterone compounds used to regulate heat
- lutenized cysts also occur (progesterone induces endometrial hyperplasia)
equine cystic ovaries
cysts can develop during winter anestrus period but are usually non-functional
dog/cat cystic ovaries
- old age
- follicular cyst (heat, swollen vulva, mammary hyperplasia)
- estrogen causes development of fibroids (smooth muscle tumors in female tubular genital tract) - fibromyomas
- retained CL (progesterone keeps animal out of heat, endometrial hyperplasia, pyometra)
stromal tumors general info
- not specifically gonadal
- fibroma, etc from CT in ovary
sex cord tumors general info
- tumors derived from follicle
- specifically gonadal (from follicle)
- granulosa-theca cell tumor (derived from stratum granulosum of follicle, CT from theca interna of follicle, or from luteal cells from CL, or combination of all 3)
germ cell tumors general info
- germ cells are primordial cells (earliest trace of structure within embryo)
- dysgerminoma, teratoma
surface epithelial tumors from ovarian surface epithelium (general info)
cyst adenomas and carcinomas
general features of ovarian tumors
- occur in older animals
- often bilateral in the dog
- usually unilateral in cow/horse
occurrence of granulosa-theca cell tumor
- derived from follicle
- older animals (cow, mare, dog)
- unilateral
- benign
gross appearance of granulosa-theca cell tumor
- surface is smooth
- cut surface is solid or cystic
- can get quite large
microscopic appearance of ganulosa-theca cell tumor
- granulosa cells (rosette formation, presence of call-exner bodies)
- fibroblastic cells (thecal cell tumor)
- luteal cells (luteal cell tumor)
- all may be seen in different areas of the same tumor
function of granulosa-theca cell tumor
- often function (secretes estrogen, testosterone in some horses - luteal cells produce progesterone)
- mare: anestrus, continued estrus, or stallion-like behavior - atrophy of other ovary
- cow: prolonged estrus
- bitch: cystic and endometrial hyperplasia and pyometra
dysgerminoma info
- tumor of germinal cell origin (oocytes)
- occurs in dog, cow, sow
- gross appearance like seminoma of testis (smooth, white, soft, friable)
- microscopic appearance: like seminoma of testis (large anaplastic cells, high mitotic index, lymphocytes)
- nonfunctional
- metastases in 10-20% of bitches
teratoma info
- germinal cell origin (rare)
- arise from single germ cell having undergone first meiotic division
- tumor composed of more than one germ layer
- bulls, sows, cows, mares
- well-differentiated, benign
- microscopically can see hair, neural tissue, CT, cartilage
ovarian adenoma/carcinoma info
- arise from surface epithelium of ovary
- primarily in dogs
- can be either benign or malignant
gross findings of ovarian adenoma/carcinoma
- bilateral-rough surface
- proliferate out of ovarian bursa
- implant on peritoneum
- metastases plug lymphatics through the diaphragm and therefore abdominal cavity filled with fluid (ascites)
microscopic features of ovarian adenoma/carcinoma
- cystic - cystadenomas - low cuboidal epithelium lining cyst
- cystic with papillary protrusions into lumen - papillary cystadenoma - papillary cystadenocarcinoma if malignant
hydrosalpinx
- distention of oviduct with fluid
- obstruction of tube –> developmental problems (white heifer disease), trauma/inflammation (rectal palpation, expression of CL)
salpingitis
- inflammation of oviduct
- ascends from uterine infection
- trauma
- may progress to adhesions, obstruction, infertility
pyosalpinx
- filled with pus (follows uterine infection)
- wall thickened with inflammatory cells (can lead to peritonitis)
