Equine - Pregnancy and Twin Management Flashcards
If a mare is not pregnant, _____ will be secreted, ____ will occur, and the mare will ______ to ______.
prostaglandin, luteolysis, return estrus
What signal causes the CL to persist in a pregnant mare?
MRP signal
When does the embryo enter the uterine lumen?
5-6 days post-ovulation
How would you characterize the movement of the embryo around the uterus?
passive
What structure forms during embryonic movement?
the embryonic capsule
What day during embryonic movement is critical for MRP?
day 14-16
By when is the embryo fixated?
day 16-18
What are some non-specific pregnancy indicators?
No return to estrus, visual assessment, vaginal speculum examination, milk/serum progesterone assay, equine chorionic gonadotropin detection, and estrogen detection
What is assessed via visual assessment/abdominal ballottement when determining pregnancy?
Pear shaped abdomen by 5-6 months, direct ballottement, fetal movement observation, fetal drop in a ventral position
When would vaginal speculum examination be done to determine pregnancy? Is it recommended?
18-21 days post ovulation - not recommended
What would the cervix look like on vaginal speculum examination if a mare was pregnant?
Dry, pale white, tightly closed, with external os protruding into the center of the cranial vagina
When would a milk/serum progesterone assay be done and what would a result greater than 4 ng/ml indicate?
18-20 days post ovulation - would imply presence of a functioning CL
What is equine chorionic gonadotropin produced by?
endometrial cups
When is ECG produced?
40-120 days in gestation
When is it best to detect for higher than normal estrogen levels?
60-240 days of pregnancy
Are any of the non-specific pregnancy indicators reliable?
no
What are some specific pregnancy indicators?
transrectal palpation and transrectal ultrasound
When is transrectal palpation performed?
20 days or later post ovulation
What can be detected if a mare is pregnant on transrectal palpation?
toned uterus and cervix, pronounced ovarian follicular activity, and swelling at the base of the horn (ping pong size early on)
At 20-30 days post ovulation, what can be found on trans-rectal palpation?
prominent uterine and cervical tone and bulge swelling on the antero-ventral base of the horn
What size will the bulge be at 35-40 days post ovulation?
about tennis ball sized
What size will the bulge be at 45-50 days post ovulation?
softball sized
What size will the bulge be at 60-65 days post ovulation?
football sized
What size will the bulge be at 100-120 days post ovulation?
basketball or volleyball sized
What can be felt on transrectal palpation at 150-210 days post ovulation?
enlarged uterus - difficult to feel the fetus and structures
What can be palpated 240+ days post ovulation?
a fetus to some extent
What is the gold standard for pregnancy detection in a mare?
transrectal ultrasound
When is visualization of the fetus poor?
from 3-6 months of gestation
What can be detected via transrectal ultrasound?
diagnosis of pregnancy, viability of the fetus, twin detection, vesicle growth measurement, and late term placental health
How early can transrectal ultrasound detect a pregnancy?
less than 10 days post ovulation; it is 99% accurate at 15 days