Lecture 7 Flashcards
What is our role as the vet during equine pregnancy?
Early diagnosis of pregnancy Monitoring embryonic development Sexing the fetus Monitor wellbeing of fetus Diagnose problems Monitor effects of treatment
What are some methods for pregnancy diagnosis
Behavioral assessment Vaginal speculum exam Transrectal palpation Transrectal ultrasonography Hormonal assays
Behavioral assessment
Is the mare coming back into heat?
Very non-specific
Vaginal speculum exam
Examine external cervical os
Progesterone= long, tight, pale, dry
Nonspecific and not commonly used because if the mare is pregnant you don’t want to put speculum in the vagina
Transrectal palpation
Rapid
Economical
Useful at all stages
Easy to make mistakes
US diagnosis of pregnancy
As early as 9 days post ovulation
Done routinely at 14 days post partum
Hormonal assays
Progesterone- 18 to 21 days after ovulation
Ecg- 36 to 120 days of gestation
Estrogens- after day 60
What does progesterone at 18 to 21 days mean?
Pregnant, persistent CL, early embryonic death
What does eCG at 36-120 days gestation?
Pregnancy or persistent endometrial cups
What does estrogen after day 60 indicate?
Fetal viability
What are you looking for during palpation when diagnosing pregnancy?
Done 14-18 days
Good tone in tubular tract
Distinct uterine bifurcation
Active ovaries
Tightly closed cervix
Can give many false positives
What will you see on US when diagnosing pregnancy?
Perfectly round embryonic vesicle
When and how can you diagnose twins
Ultrasound in day 14-16 gestation
How to manage equine twins?
When is the best time?
Manual embryo crush
Day 16-17 (mobile phase)
Which embryo should you crush in the case of twins?
Always the one that is in the better position for you to get to
What will you see on US at day 17-18
The embryo changes shape from perfectly round to triangular (guitar pick)
Slight uterine edema
What will you feel on palpation from day 20-25?
US at day 20-25?
Toned uterus
Narrow, elongated cervix
Guitar pick to irregular shape, embryo proper by day 21, heartbeat by day 24
What membrane is being formed at day 25?
Allantois
What will you feel on transrectal palpation on day 30-35?
US on days 30-35?
Toned uterus
Narrow, elongated cervix
A bulge at the base of uterine horn
Regression of yolk sac
Dorsal migration of embryo (~half way up embryo)
Development of fetal membranes
Where is the embryo proper at day 35?
All the way at the top of the embryonic vesicle
What are some things that cause early embryonic death?
Uterine edema
No embryo proper
No heart beat
Collapsing vesicle
What will you feel at day 35-40?
See on US?
Good uterine tone
Narrow, elongated cervix
Tennis ball shaped bulge
Transition from embryo to fetus (organogenesis is completed)
Formation and attachment of umbilical cord
Migration of fetus ventrally
Describe the migration of the embryo
Embryo begins at the bottom About halfway up at day 30 All the way up at day 35 Half way down at day 40 All down at day 45
What will you feel at day 45-50?
See on US?
Same thing with uterus and cervix as before
Softball size bulge
Elongation of umbilical cord
Further migration of the fetus ventrally
What happens if you realize you have twins after day 40?
This is after endometrial cups have formed…so mare won’t cycle until day 120 even if you abort the fetuses
What can you do to management fetal twins after day 40?
Transvaginal ultrasound guided aspiration
Very low success rate
What will you feel at day 60-65?
Less tone in gravid horn and more tone in non-gravid horn
Vesicle is expanding into the uterine body
Child size football shape
How to manage twins at day 60-110?
Cranio-cervical dislocation through flank incision
How to identify gender?
Use the gender tubercle- is in the back (female) or more cranial (male)
What do you feel at day 75-120?
Uterus is pulled ventrally and ovaries are at midline Basketball shape (need to differentiate from bladder by following the cervix)
Difficult to image transrectally at this stage
How to manage twins at day 110-150?
Transabdominal ultrasound guided cardiac injection with KCl or procain penicillin
What is going on at day 150-200?
Uterine descent is complete
Fetal ballottment is consistent
Best approach is transabdominal US
What should you be monitoring late gestation?
Transrectal US: Fetal orbit (fetal age) Placenta (integrity and thickness) Fetal fluids (echogenicity)
Transabdominal US:
Fetal HR
Fetal fluids
Placenta
If you measure combined thickness of uterus and placenta and/or see separation between the fetal membrane and the uterus, what are you thinking?
Ascending placentitis
