Dog Infertility and Subfertility Flashcards
what is infertility
the inability to conceive and produce viable offspring
what is the most common cause of infertility/subfertility
poor bitch breeding management (no/poor ovulation timing)
it is important to distinguish split heat from
shortened diestrus/anestrus phase (shortened inter-estrus interval)
it is important to distinguish persistent estrus from
vaginitis
persistent estrus is diagnosed as
cornified cells > 30 days on cytology without a rise in progesterone
what usually causes persistent estrus
reproductive tract pathologies with secreting hormones
T/F vaginal structure abnormalities are common in the bitch
T
what is the difference between primary and secondary anestrus
primary present since birth: never came into heat
secondary means >10-18m since last heat
T/F vaginal structural abnormalites can be congenital or form after birth
F; always congenital
what are 3 examples of vaginal structural abnormalities
1) vaginal septum
2) persistent hymen
3) vaginal circumferential stricture
what can vaginal structural abnormalities cause
- vaginitis
- infertility/subfertility (painful to copulate; blocks sperm)
- UTIs, urinary incontinence
what is the best way to diagnose vaginal structural abnormalities
digital palpation
to treat vaginal septum, where should you incise and why
cranial as possible to avoid the urethra
vaginal hyperplasia occurs in response to what hormone
estrogen (proestrus and estrus; just before whelping)
what breeds are predisposed to vaginal hyperplasia
brachycephalics
vaginal hyperplasia ALWAYS originates from what location
the vaginal floor, just cranial to the urethral papilla
if large enough, vaginal hyperplasia will cause
vaginal +/- urethral prolapse
what are sequelae of vaginal hyperplasia
- secondary infections
- self-mutilation
- issues urinating
- inability to breed naturally
what is a serious consequence of vaginal hyperplasia just before whelping
obstructive dystocia
why does it not make sense to surgically remove vaginal hyperplasia
it is going to recur at next heat
if you induce ovulation to treat vaginal hyperplasia, what is a consequence
cannot breed in this cycle
it is important to differentiate vaginal hyperplasia from (2)
vaginal polyps and vaginal tumors
vaginal tumors are usually
leiomyomas or leiomyosarcomas
what breeds are predisposed to DSD (dogs)
Miniature Schnauzers, Cocker Spaniels
os clitoris, persistent mullerian duct syndrome, segmental aplasia of uterus, hypoplastic ovaries are all examples of
DSD
ovarian cysts can be in what two locations
within the ovary (true ovarian cyst) or adjacent to the ovary (paraovarian cyst)
follicular cysts secrete _________, which can cause (4)
estrogen; persistent estrus, vulvar swelling/discharge, hyperestrogenism (ex. anemia), cornification
how do we diagnose and treat follicular cysts
diagnosis: ultrasound
treatment: spay or induce ovulation medically
T/F ovarian neoplasia is realtively common in dogs
F
what is the most common ovarian neoplasia in dogs and what does it secrete/some sequelae
granulosa cell tumor; estrogen (can also secrete progesterone); signs of persistent estrus
how do you treat granulosa cell tumors in dogs
spay; chemo if metastatic
how can you diagnose granulosa cell tumors in dogs
- cornified vaginal epithelium
- ultrasound
- history and clinical signs of hyperestrogenism
what are clinical signs of ovarian remnant syndrome
estrus and pseudopregnancy signs
before diagnosing ovarian remnant syndrome, it is important to rule out
exogenous hormone exposure
what are 5 diagnostic options for ovarian remnant syndrome and what is the expected values if positive
1) estrogen detection -> cornified cells
2) progesterone -> high if later in cycle
3) LH test -> high in a spayed animal
4) AMH -> present
5) ultrasound -> ovarian remnant
what is endometritis and what are the consequences
inflammation of the endometrium; causes infertility/subfertility
what are 2 ways to diagnose endometritis in dogs
1) vaginal cytology
2) endometrial culture, biopsy and cytology
cystic endometrial hyperplasia is a __________ disease that is more common in ________ bitches
progressive; older (more non-pregnant cycles)
what causes cystic endometrial hyperplasia
abnormal response to uterine stimulants (ex. estrogen and progesterone) that causes hyperplasia of endometrial glands, forming cysts
why does CEM cause subfertility/infertility
prevents migration and implantation of the embryo
pyometra is a ______ dependent disease that occurs in _______ and NEVER ___________
progesterone; diestrus; postpartum
what two uterine diseases can commonly occur together because one predisposes to the other
CEM -> pyometra
what is the most common bacteria cultured from pyometra
E. coli
what are clinical and CBC signs of pyometra
lethargic, anorexic, PU/PD, vomiting, may have vaginal discharge
CBC: leukocytosis with degenerative left shift (neutrophilia)
what is the important of the history for pyometra
was in heat 3-10 weeks ago
what is the surgical tx for pyometra
OHE (stabilization with IV fluids, antibiotics)
what is the medical tx for pyometra
- aglepristone
- PGF2a once cervix open
- antibiotics
- IV fluids
- breed next cycle to prevent from recurrence
what are the most common infectious causes of infertility/subfertility
Brucella canis, Canine herpes virus, Ureaplasma, Mycoplasma
what is a classic sign of Brucella canis
late-term abortion (2 weeks prior to whelping)
T/F Brucella canis is zoonotic
T
what non-reproductive disease does brucella canis cause
uveitis, spondylitis, lymphadenopathy
how is brucella canis diagnosed
rapid-slide agglutination test, followed by further testing
why is treating brucella canis difficult
lifelong infection with intermittent infection
what are treatment options for brucella canis
neutering/spay with long term antibiotics; in kennels euthanasia of all affected animals
what does canine herpesvirus 1 cause
EED, abortion, stillbirth, neonatal death (largest puppies affected)
when does exposure to canine herpesvirus 1 become problematic
when naive bitches are exposed during pregnancy
T/F treatment of canine herpesvirus 1 is usually not rewarding once clinical signs are already present
T
how can we prevent canine herpesvirus 1 infection in pregnant bitches
- isolate infected animals
- do not expose first time bitches to unknown animals
- optimal hygeine
- keep temperature warm
what are organisms that are normally commensals of the reproductive tract that can cause infertility
mycoplasma and ureaplasma, E. coli
when interpreting results from a guarded vaginal swab that was then cultured, what do you want to be looking for?
- pure culture
- heavy growth
- correlated with clinical signs
- cultured repeatedly
how does sterilization differ from contraception
sterilization is permanent termination of reproduction whereas contraception is temporary suppression of reproduction
what are the 3 reasons to sterilize
1) prevent unwanted pregnancy
2) prevent reproductive pathologies
3) prevent unwanted behaviours
what method of contraception is associated with bad reactions and is currently off the market
intra-testicular injections
what method of sterilization is not recommended
vasectomy (hard to do, can reverse, dogs can self-mutilate)
what are the benefits of spay prior to 1st heat?
- reduced risk of mammary neoplasia
- removes risk of pyometra
what are the adverse effects of spaying before 1st heat
- cancer
- orthopedic disease
- obesity
- urethral sphincter mechanism incontinence
what are the benefits of neutering
- removes risk of testicular disease
- removes risk of prostatic disease
- reduces roaming risk
- reduces undesired behaviours
what are adverse effects of neutering
cancer, obesity, orthopedic disease
what will NOT be impacted by neutering prepubertial vs at 1-2 years old
testicular and prostatic disease risk
In general, you can recommend spay/neutering at what age unless __________
6 months; unless large breed
what are the 3 categories of contraceptives
steroid hormones, protein hormones, contraceptive vaccines
T/F efficacy and reversal of contraceptives is variable
T
what steroid hormone contraceptive should never be used
estrogen (used for mismating but has serious side effects such as pyometra and bone marrow suppression)
how to progestins work as a contraceptive and when should they be given
inhibit gonadotropin release via negative feedback loop; only give in ANESTRUS (when estrogen levels are low)
using progestins, a return to estrus can be expected in ________ months, but may take
9-12m; 2-3 years
what type of contraceptive is associated with pyometra, mammary tumors, diabetes, acromegaly, immunosuppression, alopecia, increased appetite, weight gain, lethargy, restlessness…
progestins
how do androgens work as a contraceptive and how long do they usually last for
inhibit LH via negative feedback loop; return to estrus in 1-7 months
what type of contraceptive causes clitoral hypertrophy, vaginal discharge, vaginitis and male-type behaviours
androgens
what are the 2 protein hormone options for contraceptives and what is the big difference between them
1) GnRH agonists
2) GnRH antagonists
agonists will cause an initial “flare” effect of estrus induction followed by down-regulation of LH and FSH
between the two protein hormone contraceptives, which is available as an implant vs an injection and which lasts longer
GnRH agonists for both
what are the 2 vaccine contraceptives and do they work well in dogs
1) porcine zona pellucida vaccine
2) GnRH vaccines
do not work well in dogs
what is the best method for inducing ovulation
dopamine agonists (cabergoline, bromocriptine)
what is the most useful contraception method
GnRH agonists
