Is She In Foal? Flashcards
Methods of PD and times at which they can be used?
- Transrectal ultrasound – from d12 (15 common).
- Elevated plasma progesterone – d18-20.
- Failure to return to oestrus – d18-21.
- Transrectal palpation – from d21.
- Plasma equine chorionic gonadotrophin d60-120.
- Transrectal ballottment of foetus – d80.
- Oestrone sulphate (plasma) – d100-150.
- Urine oestrogen – d120-150.
- Birth – 11m11d (ish).
Transrectal palpation…
1. What does normal luteal phase feel like?
2. What does it feel like from d21 preg?
3. What does it feel like from d40 preg?
4. What does it feel like from d60 preg?
- Uterus becomes more tonic, cervix closed (hard).
- Conceptual swelling protrudes at base of one horn and usually bulges ventrally.
- Extensive ovarian activity (under eCG) results in ovarian enlargement.
Uterine swelling continues to increase in size and is spherical. - Swelling is approx. 12cm diameter and fills pregnant horn and may involve uterine body.
Transrectal palpation…
1. What does it feel like from d90?
2. What does it feel like from d120?
- Whole uterus filled w/ fluid and more ventral in position.
- Distinction between b body and horns difficult.
- Uterus may be difficult to palpate and foetus may not be balloted.
- Whole uterus filled w/ fluid and more ventral in position.
- Follicular activity ceases and ovaries become progressively smaller.
- Significant tension is present in ovarian ligament and the utero-ovarian ligaments.
- Ovaries move more ventrally and medially.
- Follicular activity ceases and ovaries become progressively smaller.
- What can be seen at first on transrectal ultrasound when pregnancy positive?
- What can be seen at d18 when implantation has happened?
- From d20?
- Sphere (anechoic) of 1cm diameter.
- Sphere (anechoic) of 3cm diameter.
- Takes an irregular shape.
- Time of foetal motility?
– What does it stimulate?
– What happens in this time? - What then needs to happen and why?
- 11d-16d.
– Maternal recognition of pregnancy.
– Increased tone, foetus come to rest in horn.
– Foetus gains O2 by diffusion.
– Nutrients mostly from yolk sac. - Embryo needs to implant to gain O2 and nutrients.
- From what point of pregnancy are foetal heart beat and allantoic membranes visible?
- From what point of pregnancy is allantois and yolk sac sizes equal?
- From what point of pregnancy is allantois larger than yolk sac?
- day 24.
- day 30.
- day 36 (3cm+ daily growth from here).
- d40 transrectal ultrasound?
- d50 transrectal ultrasound?
- d55-65 transrectal ultrasound?
- d60 transrectal ultrasound?
- d85 transrectal ultrasound?
- Yolk sac gone.
- Foetal limb buds.
- Genital tubercle.
- Foetal eyes.
- Foetus out of reach.
- What do you want to look for in mare 12-15d pregnant?
- 24-28d pregnant?
- 35d pregnant?
- 65-80d pregnant?
- Twins.
- Heartbeat.
- Just before endometrial cups form.
- Foetal sexing.
Consideration when ultrasound scanning?
Preg v cyst.
- Preg typically spherical at <20d and has characteristic specular reflections (artefacts).
- Cysts usually irregular.
- Pregnancies grow.
Twins (one can hide!)
- Check for 1 or 2 CL.
- Careful if scanning early.
- Be systematic.
- DDx for twins?
- How does a twin pregnancy usually occur?
- Incidence of twins in same horn?
- What % naturally reduce to single?
- What is likely to happen if not reduced to single?
- Uterine cysts.
- 2 follicles (up to 1/3 of ovulations) whch can be days apart (count CLs).
- Approx. 50%.
- manual palpation poor accuracy.
- US can still be tricky to spot. - 83%.
- Abort at 8-9mths - uterine SA no longer efficient to sustain.
- Early options for twin management?
- Later options for twin management?
- Manual rupture, where you pinch one.
Abort both w/ PG.
*must check for effect afterwards. - TUGA/Cervical luxation.
Rectal tears as complication of rectal exam…
1. Presentation.
2. DDx.
- Blood on rectal glove.
Sudden loss of rectal tone. - Blood from ulceration/proctitis.
Loss of tone w/ gas movement.
Rectal tear grading,
- Grade 1 = mucosa + submucosa damaged, medically treat or blindly suture.
- Grade 2 = only muscular layer damaged, medically treat.
- Grade 3a = Mucosa, submucosa and muscular rupture w/ serosa intact, treat w/ euthanasia, surgically or medically.
- Grade 3b = Mucosa, submucosa and muscular layers (full thickness) w/ mesocolon intact dorsally, treat w/ euthanasia, surgically or medically.
- Grade 4 = Full thickness w/ exposure to peritoneum, treat w/ euthanasia or surgically.
Rectal tear dx confirmation.
- Visualisation.
– endoscopy.
– speculum. - Palpation.
– un-gloved hand? - Abdominocentesis.
- Positioning of most rectal tears.
- Lengths of tears and associated causes.
- Dorsal-dorsolateral.
- 6cm repro exam.
4cm GI exam.
25cm dystocia.