SA 1 Flashcards
should I breed my dog for her first estrus cycle?
NO the first estrus tends to be irregular
how many estrus periods do dogs have a year?
2 on average
who reaches puberty sooner: large or small breed dogs?
small breed dogs
when does a dog reach puberty?
6-12 months of age depending on size of the dog
what is unique about ovulation in dogs?
they ovulate a primary oocyte and it need 2 days to mature to become a secondary oocyte and become fertilized
T or F: the canine oocyte fertile directly after ovulation
bonus: how long is the oocyte viable for?
false, it is not fertile until 2.3 days after ovulation
remain viable for 1 week which is quite long!
name the cell type
parabasal cell (fried egg)
round shape, large nucleus to cytoplasm ratio
name the cell type
intermediate cell (more angulated than fried egg)
more cytoplasm
name the cell type
superficial cell
angulated shape, darker, smaller nucleus
name the cell type
anuclear cell
no nucleus and angulated, these are the ones that are sloughing off
estrogen peaks during ____ and triggers _____
proestrus, the LH surge
what is unique about canine progesterone?
it rises during estrus. the initial rise coincides with LH surge and as the follicles lutenize they make progesterone. progesterone reaches really high levels, EVEN if the dog is not pregnant! (in other species, high progesterone only happens when the dog is is pregnant)
explain how progesterone can be used to time ovulation
before the LH peak it is around 1 ng/ml, the day of LH peak it’s around 2, and around ovulation it is 4-6, and when the oocyte is matured it is around 15 which is quite high
**breed 2 days after progesterone has reached 5-8ng/ml
**best to breed when P4 is 17 to 24 ng/ml
what’s a quick, cheap, and easy way to monitor a dog’s cycle?
vaginal cytology!
after dogs have mated, how long is the semen viable for?
48 hours to 11 days!! long time
can P4 levels be used alone to monitor the estrus cycle in dogs?
no, it should always be used in conjunction with other things like behavior, vaginal cytology, vaginoscopy, LH test
why do we tend to monitor P4 levels and not just do the LH test?
because the LH surge happens so quick, it’s difficult to catch it on the test
a female intended for breeding requires how long after a cycle for uterine involution/repair?
130 to 150 days
if less than 120 days, potential for infertility
explain how progestins can suppress estrus
neg feedback on HPA axsis–>reduction of gonadotropins in most species but not reliably in dogs
what are some examples of a progestin that can be used in dogs?
megestrol acetate–>dont treat more than 2 cycles in a row, and dont treat at pubertal estrus
medroxyprogesterone acetate (MPA)–>side effects are common
true or false: false pregnancies do not happen that often in dogs
false! there is a high incidence in intact females
true or false: false pregnancy is not related to pyometra
true
make sure your patient is not pregnant before you initiate treatment otherwise
you will induce abortion
why do we use dopamine agonists and serotonin antagonists as anti-prolactin drugs?
dopamine inhibits prolactin so we want a dopamine AGONIST
serotonin stimulates prolactin secretion so we want a serotonin ANTAGONIST
name 3 drugs you can use to treat false fregnancy
Cabergoline, metergolin, bromocriptinr
