Canine Pregnancy & Female Reproductive Disease Flashcards
Where does fertilization of oocytes occur in bitches? How long do sperm cells last?
uterine tube (oviducts)
5-7 days if fresh
What are 3 ways of determining whelping date? When does this not apply?
- 65 days from LH surge
- 63 days from ovulation (happens 2 days after LH surge!)
- 57 days from first day of cytological diestrus (vaginal epithelium is rounded and neutrophils are present in response to stud contamination)
singleton pregnancy - only one fetus = no overcrowding to induce fetal cortisol spike, technically gestation can be indefinite and pup can get large enough to induce dystocia)
What breed can go into whelping early?
CKCS —> early by 1-2 days
What causes the huge range of whelping date estimation when only using one date?
(58 days if bred late - 71 days if bred early)
variability of estrus in the bitch and longevity of sperm in the uterus
What kind of placentation do canines have? What unique structure does it have?
zonary endotheliochorial —> 4 layers: maternal endothenium + fetal endothelium, connective tissue, and epithelium
green pigmentation (uteroverdin) = marginal hematoma acting as an iron storage for the fetus
What is occurring if the uteroverdin is seen without the pup?
placental detachment = dystocia
What is progesterone responsible for in canine pregnancy? What is it not used for?
luteal dependence of pregnancy maintenance —> requires 2.6 ng/mL (typically gets >10-15 ng/mL)
pregnancy diagnosis (no maternal recognition of pregnancy)
How do progesterone levels change as whelping approaches?
drops, resulting in a temperature drop
When do prolactin levels increase with pregnancy? How is this related to progesterone?
lutetropic —> second half of gestation
concentration inversely related to progesterone - acts as a dopamine agonist
What is the most pregnancy-specific hormone used for pregnancy diagnosis in dogs? When do levels increase?
relaxin - produced by the placenta
day 21 of gestation
What induces pseudopregnancy? What clinical signs are seen?
decreased progesterone as prolactin increases in late diestrus, post-ovariectomy
- mammary gland enlargement with or without milk production
- nesting behaviors
When can abdominal palpation be used to diagnose canine pregnancy? What is felt?
21-28 days —> gets difficult by day 35 , but can feel fetal bodies and movement after 50 days
string of pearls
When can radiography be used to diagnose canine pregnancy? What is it used for?
day 43 —> fetal calcification
gold standard for counting pups
How is ultrasound used for diagnosing canine pregnancy? When can it be used?
confirms pregnancy and fetal viability —> CAN’T be used for counting pups
- day 17 - can see vesicle
- day 25 - can see heart flutter
What can ultrasound be used to estimate in canine pregnancies?
C-section/whelping date
What 3 features on ultrasounds are used to determine if a bitch is prepared for C-section? When are each seen?
- high kidney definition with visible cortex and medulla - 57-63 days after LH surge
- intestines - 57-63 days after LH surge
- intestine peristalsis - 62-64 days after LH surge
(determines pups’ maturity)
What 3 ways of estrous cycle monitoring are used to estimate whelping date? How is ultrasound used?
- progesterone profile
- LH assay
- cytology
fetal biometry measurements - inner chorionic cavity and biparietal diameter measurements based on size
What 8 structures are seen on radiography when determining fetal maturity? When are they seen?
- spine
- skull
- ribs
- caudal vertebrae
- fibula
- calcaneus
- paws
- teeth
all present at 3-8 days before whelping
What is the best way to assess canine fetal viability?
measuring fetal HR
- 220-240 bpm = normal HR before term
- 180-200 bpm = normal HR on whelping day (Stage II)
- 160-180 bpm = stress, mild hypoxia
- <140-160 bpm = decreased postnatal survival
Fetal intestinal ultrasonographic definition:
- needs to be completely functional for colostrum digestion
- 5 days before parturition = spaghetti-like, prominent development, when a C-section can occur
Fetal renal corticomedullary definition:
medullar and cortex are better differentiated by ~5 days before parturition
What causes diestrual diabetes mellitus?
increased progesterone from the CL causes GH to be secreted from the mammary glands and IGF1 secretion from the liver —> decreased insulin sensitivity
When is pregnancy toxemia most common? What occurs?
late-term pregnancy with large livers
anorexic mothers with increased energy demand causes the metabolism of large amounts of fat, resulting in ketonemia, ketonuria, and hepatic lipidosis
How is pregnancy toxemia treated? What can happen in severe cases?
enteral and/or parenteral glucose supplementation
pregnancy termination
What are 5 possible signs of impending canine labor?
- decreased appetite
- restless, panting, anxiousness
- declining levels of progesterone 48 hours prior causes body temp to decrease by 1-2 degrees (~98 F) usually 12-24 hours before
- presence of colostrum 1-7 days prior (unreliable)
- nesting behavior 12-24 hours prior
What is a recessed vulva? What 2 things is it associated with?
juvenile/hooded vulva due to excessive skin folds covering the dorsal aspect
- early OVH
- ascending bacterial infections - perivulvar dermatitis, UTI, incontinence due to urine pooling
What are 2 treatment options for recessed vulvas?
- topical cleansing*
- valvuloplasty/episioplasty
What is clitoral hypertrophy? What are the 2 most common causes?
enlarged tissue in the ventral clitoral fossa +/- development of os clitoris
- progestogens/androgens during pregnancy
- DSD - inherited in GSP, Beagles, English Cocker Spaniels
What treatment is recommended for clitoral hypertrophy?
milberone (androgen) - suppresses estrus
When is vaginal fold hyperplasia (prolapse) most commonly seen? What causes it?
proestrus, estrus, late pregnancy —> tissue from ventral vaginal floow becomes extremely edematous (not true prolapse)
hypersensitivity to estrogen with recurrence in next cycle - normalizes with estrogen decrease as progesterone rises
What are the 3 stages of vaginal fold hyperplasia? What can it cause?
- swollen internally
- ventral floor becomes edematous, commonly in a pear shape
- dorsal portion of vagina becomes involved, becomes more of a dome shape
impaired breeding, dysuria
What are the 3 most common causes of vulvar discharge?
- vaginitis
- CEH-pyometra complex
- SIPS
In what individuals is vaginitis most commonly seen? What are 2 predisposing factors?
spayed females, due to decreased estrogen (decreased mucosa development)
- congenital anomaly
- neoplasia - TVT, leiomyoma
How are adult and juvenile vaginitis treated?
ADULT - systemic antimicrobials, probiotics
JUVENILE - typically resolves after first estrous cycle without antibiotics - mucosa will become thicker with development
What is the most common cause of cystic endometrial hyperplasia (CEH) in canines? In what bitches is it most common?
repeated exposure to steroidal hormones, where progesterone predominates over estrogen (multiple rounds of estrus) with aggravation as estrogen also increases
intact bitches >9 y/o
When does pyometra occur in canines? What causes it? What is the most common bacterial etiology?
diestrus —> high progesterone
progesterone causes cervical closure, decreased myometrial contractions, and leukocyte inhibition
E. coli
What is pyometra commonly confused with on ultrasound/radiographs?
- hydrometra
- mucometra
- hematometra
What clinical signs are associated with open and closed pyometra?
OPEN - mucoid/purulent vulvar discharge
CLOSED - abdominal distension, more severe systemic signs of endotoxemia (LPS endotoxin) and PU/PD
What diagnostics are used for pyometra?
- radiographs
- ultrasound
- bloodwork - leukocytosis with neutrophilia and a left shift
What treatment is recommended in non-breeding and breeding females with pyometra?
surgical removal of uterus and ovaries
- PGF2a - luteolysis + uterine contraction, cervix MUST be open
- cabergoline - dopamine agonist decreases luteotrophic prolactin
- aglepristone - progesterone antagonist
- antibiotics
What are uterine serosal inclusion cysts?
common incidental finding in older bitches believed to arise when mesothelial cells becomes trapped in the serosa —> continue to secrete and become hyperplastic
- C-section adhesion traps mesothelial cells
- usually does not affect fertility
What is subinvolution of placental sites (SIPS)? In what bitches is it most common?
delay in the involution of placental sites characterized by fresh blood discharged from the vulva > 6 weeks post-partum (remaining fetal debris is passed before) —> varying degree of hemorrhage can be fatal
primiparous bitches <3 y/o
What is seen on vaginal cytology in cases of SIPS? Is treatment commonly necessary?
trophoblast-like cells invade endometrium
spontaneous remission is common, monitor for heavy bleeding and perform OVH if needed
What do follicular and luteal cysts secrete?
estrogen
progesterone
What 2 types of tumors are most common in the female canine reproductive tract?
- ovarian epithelial tumors - subepithelial structure origin, causes ascites and abdominal distention
- granulosa cell tumors - often functional and result in elevations in estrogen and persistent/erratic estrus
What is the most common cause of ovarian remnant syndrome? What are 3 options for diagnosis?
iatrogenic - remnant left behind after surgery, resulting in revascularization and estrogen secretion
- AMH - ovarian granulosa cell source, will be positive with remnants
- progesterone - increases with presence of follicles and ovulation, will be high with remnants
- LH - high levels in spayed individuals due to loss of negative feedback, will be low in remnant cases
What are the predisposing causes of mastitis? What 2 time periods are most common?
teat trauma and milk retention
- 1-3 weeks after parturition - maximal milk production
- after weaning - mammary glands become distended
How do affected glands appear with mastitis? What other signs are seen?
swollen, warm to the touch, discolored or painful + discolored milk (red/brown)
- offspring fail to gain weight
- fever
- anorexia
- tachycardia
- SEVERE CASES: abscessation, gangrene, septic shock
