Female repro - uterus Flashcards
uterine torsion
- twisting or rotation of a part along its axis
- affects pregnant uterus (cattle esp)
- rotates cervix –> outcome depends on degree of rotation (circulatory problems)
- sequela –> ruptured uterus (fetus can enter abdomen and become mummified, if cervix is open fetus putrefies)
uterine prolapse/eversion
- cow and ewe
- decreased uterine tone (hypotony) –> often associated with hypocalcemia (prolonged dystocia, retained placenta)
- uterus turned partially inside out
- complete eversion of uterus (intestine, uterine horn, bladder inside prolapsed horn –> necrosis)
- death, shock, hemorrhage, loss of fluid/body heat
uterine rupture
- seldom spontaneous –> torsion, prolonged dystocia, obstetrical procedures
- most fatal (hemorrhage, secondary peritonitis)
hyperemia and edema
- severe at estrus - bitch at proestrus (diapediis –> bleeding from intact vessel)
- hyperemia associated with inflammation
uterine hemorrhage
- dog/cat: normal hemorrhage at periphery of placentation
- following torsion, uterine eversion
- due to endometrial hyperplasia
- due to neoplastic conditions
endometrial atrophy
- loss of trophic ovarian function
- senility (old dogs)
- following ovariectomy
- in disorders of sexual development
- normal in mare during winter anestrus
- endometrium is flattened, underlying stroma is condensed and contains inactive glands
etiology of endometrial hyperplasia in species other than the dog
- produced by prolonged estrogenism
- functional ovarian follicular cyst or granulosa cell tumor
dogs and endometrial hyperplasia
- occurs with estrogen coupled with prolonged progesterone
- hormonal activity by ovarian tumors may lead to it
- most ovaries in dogs with it contain normal CL
- develops during long luteal phase
- not a pre-cancerous change but irreversible
pathogenesis of canine endometrial hyperplasia
- estrogen binds to estrogen receptors in endometrial epithelial cells and induces formation of intracellular progesterone receptors
- progesterone causes secretion by endometrial glands
- timing/duration of estrogen priming important
- bacteria almost always present
- drug induced progesteronism (used to keep dogs out of heat)
gross appearance of cystic endometrial hyperplasia
- uterine glands become hyperplastic and hypersecretory
- dog: uterine mucosa thickened, grossly visible cysts with clear watery content
microscopic appearance of cystic endometrial hyperplasia
- hyperplasia of surface epithelium
- hyperplasia of glandular epithelium (papillary protrustions into lumen)
- glands dilated - filled with fluid
conditions that follow cystic endometrial hyperplasia
- hydrometra (excess fluid in uterine lumen)
- mucometra (mucoid material in lumen)
- pyometra (uterus contains pus)
adenomyosis
- benign condition characterized by in-growth of endometrium in myometrium
- occurs in bitch, queen, cow
endometriosis
- endometrium located outside the uterus
- occurs only in animals with menstrual cycle (nonhuman primates, women)
what does most uterine inflammation begin as
endometritis (inflammation of innermost layer of uterus –> endometrium)
estrogen v progesterone in uterine infections-
- uterus under estrogen: resistant to infection (increased motility - physical clearance, neutrophil migration)
- uterus under progesterone: susceptible to infection (increased secretion, immunosuppressant substances that inhibit lymphocytes
postpartum uterine infection occurrence
after abnormal birth (twins, abortion, retained placenta, dystocia)
causes of postpartum uterine infections
- lochia (fluid in uterus after parturition)
- organisms enter through cervix
- streptococci (horses)
- arcanobacterium oyogenes, e coli (cattle)
- clostridium
progression of uterine involution
- varies with species
- mare: 9 days
- cow: caruncles dequamate in 10 d, endometrial epithelial repair done by day 50
what diminishes uterine tone
- excessive stretching (twins) - hydrops
- general debilitation
- absorption of toxins
what is endometritis
- inflammation of endometrium
- uterine mucosa only –> sometimes caused by mild infection
- mildest forms occur as post breeding infections (tritrichomonas foetus, campylobacter, tayorella equigenitalis)
- may cause early embryonal death
gross appearance of endometritis
- opacity of mucus
- dark red mucosa
microscopic appearance of endometritis
- leukocytes in mucosa
- neutrophils, plasma cells, lymphocytes in lamina propria
what is metritis
- inflammation of entire uterine wall
- all layers of uterine wall inflamed - usually immediately after parturition
features of metritis
- wall is flaccid and atonic
- wall thickened with edema fluid, friable
- serosa has hemorhage, fibrin tags
- content - scant or abundant, malodorous, yellow to red-black
microscopic lesions of metritis
- suppurative inflammation with edema, leukocyte infiltration
- hemorrhage and necrosis of endometrium
- thrombosis of vessels
sequela of metritis
- death (toxemia)
- pyemia (pus in blood –> endocarditis)
- salpingitis
- chronic metritis and endometritis
- pyelonephritis
chronic metritis and endometritis
- sequela of metritis
- plasma cell accumulations and fibrosis in submucosa
- lamina propria replaced by granulation tissue
- cystic glands
- common cause of early embryonal death in older mares
- diagnosis by endometrial bx
endometritis and metritis
- endometritis usually not from extension of metritis
- usually from uterine perforation caused by poor placement of infusion pipette, forced fetal extraction
what is pyometra
- acute or chronic suppurative inflammation of the uterus with accumulations of pus in the lumen
- cervix is either partially or completely closed
- cow, dog
causes of pyometra
- mechanical: scarred due to injury at birth or from iatrogenic causes –> fibrosis, cervical stenosis
- anomalies: segmental aplasia
- physiological cervical obstruction (most common): cervix partially closed –> requires influence of progesterone from functional or retained CL
pyometra of cow
- pre-existing uterine infection, course altered due to progesterone
- uterine infection causes reduction of PGF2a (luteolytic) –> retained CL
- retained CL produces progesterone –> uterus more susceptible to infection –> cervical closure, no myometrial contractions
clinical and gross features in cow pyometra
- usually in postpartum cow
- retained CL
- cervix partially closed (no cervical mucus plug)
- pus in vagina
- cow not sick or febrile
- uterus somewhat swollen and flaccid (contains pus)
- not usually life threatening
when does pyometra of dog/cat occur
- infected inflammations superimposed upon cystic endometrial hyperplasia subsequent to prolonged hormonal imbalance
- many cases occur during pseudopregnancy
pathogenesis of canine/feline pyometra
- functional CL: produces cystic endometrial hyperplasia, increased secretion of uterine glands
- progesterone makes uterus susceptible to infection
- cervix functionally or partially closed
- link to bacterial infectiob
clinical signs of canine/feline pyometra
- older animal (over 6)
- acute disease –> vomiting, anorexia, lethargy, PU/PD, vaginal discharge
- pendulous abdomen from pus in uterus
- leukocytosis
- vaginal discharge
gross appearance of canine/feline pyometra
- severely distended uterus
- serosal surface congested and black
- wall is friable –> uterine rupture, peritonitis
- secondary infections
microscopic features of canine/feline pyometra
- cystic endometrial hyperplasia
- inflammation superimposed (lumen filled with neutrophils, neutrophils in endometrium, plasma cells/lymphocytes in lamina propria)
sequelae of canine/feline pyometra
- death from toxemia
- intermittent bacteria
- myeloid hyperplasia of bone marrow
- membranoproliferative glomerulonephritis
- polyuria
pyometra of mare
- most but not all follow postpartum infections
- most continue to cycle during dz (may be irregular)
- hormonal influences not important
- weight of pus in uterus may keep it from emptying
- endometrial damage decreases PGF2a
- streptococci
early embryonal death info
- embryo: first trimester of pregnancy
- common in most species (fertilized ova degenerate, reabsorbed, discharged)
- prolonged time between estrus cycles
etiology of early embryonal death
- embryo chromosomal abnormality
- mild uterine infection
- viral infection
- unknown (most common)
what is a fetus defined as
later stage of development after skeletal ossification (2nd or 3rd trimester)
abortion
expulsion of the fetus prior to time of expected viability
stillbirth
dead fetus delivered within a time of expected viability
fetal death in monotocous animals (one offspring per litter)
- early fetal death: incomplete resorption
- late fetal death: expulsion
fetal death in polytocous animals (large litters)
- if all fetuses die at same time: abortion
- if few die: mummification (others live until term)
fetal mummification
- in utero desiccation of dead fetus
- often in pigs (cows - fetus retained indefinitely)
- bacterial infection not present
- gross: fetus dark brown and leathery, membranes may be tightly adhered
- cervix closed up until time of expulsion
- no long term adverse effects on breeding
fetal maceration
- in utero putrefaction of dead fetus
- depends on bacterial infection of low virulence - endometrtitis
- some of fluid of maceration absorbed
- remaining tissue expelled
- CL regressed, cervix open
- dystocia, incomplete abortion
emphysematous fetus
- dead fetus in utero infected by gas forming bacteria
- bacteria usually enter through cervix
- usually occurs near term - dystocia, cervix open
- fetus distended with gas
- often fatal to damn
when does intercodyledonary placentation develop
when size and numbers of regular placentomes are insufficient
deficiency/damage to placentation
- deficiency on dam’s endometrial side of placenta (caruncle)
- damage usually due to infection
compensation in placentation
- increase in size of remaining caruncles, may fuse
- new caruncles develop between larger ones
- placental attachments to new caruncles are insecure and pregnancy ends in abortion/hydroallantois
what is hydramnios/hydrallantois
- hydramnios: hydrops of the amnion
- hydrallantois: hydrops of the allantois
- accumulation of excessive fluid and edema in fetal membranes combined with fetal anascara (generalized infiltration of edema fluids into SQ CT)
- cows only
what are hydramnios and hydrallantois due to
- hydramnios: fetal malformation
- hydrallantois: adventitial placentation
what do hydroamnios/hydrallantois lead to
- dystocia
- uterine paralysis
- retained placenta
- acute metritis
amniotic plaques
- placenta slowly degenerates throughout normal pregnancy
- focal areas of squamous metaplasia on internal surface of amnion and on umbilical stump
- flat and discrete
- commonly mistaken for placental lesions
- amniotic plaques found in normal placenta
serosal cysts
- thin fluid-filled cysts on serosal surface of uterus
- seen in postpartum bitch/cow
- retention cyst from pinched off segments of serosal epithelium (occurs during involution of postpartum uterus)
fetal lung and bacterial abortion
bronchopneumonia (brucellosis, acranobacterium pyogenes)
placenta and bacterial abortion
- placentitis
- yellowing –> necrosis
- blood-tinged cotyledons and inter-cotyledonary areas
- thickened placental membranes (opaque)
liver and bacterial abortion
- focal hepatic necrosis
- listeriosis: cattle, 1-2mm focal pale areas in liver (gram + rods)
- campylobacter fetus subsp fetus: sheep, 1cm necrotic areas in liver
heart and bacterial abortion
pericarditis as evidenced by thick pericardium containing fibrin strands
abdominal cavity and bacterial abortion
fibrin strands suggest peritonitis
mycotic abortion
- placenta: severely thickened and necrotic placental membranes (placentitis and placental necrosis)
- skin: focal dermatitis
- lung: bronchopneumonia
liver and viral abortions
- multifocal necrosis, 1mm pale foci
- IBR, equine rhinopneumonitis virus, pseudorabies
viral abortions and early embryonic death
- BVD virus
- porcine parvovirus
viral abortions and embryonal developmental arrests
cerebellar hypoplasia (BVD, hog cholera, feline panleukopenia)
examples of protozoal abortion
- toxoplasma gondii (sheep)
- neospora caninum (cattle, dog)
lesions in protozoal abortion
- non-suppurative encephalitis and meningitis
- non-suppurative myositis and myocarditis
- mineralization of the placenta (small white foci of mineral)
- prozotoal cysts hitologically
