Preparation for parturition Flashcards
Describe the health programme/foaling environment to prepare for parturition
- vaccinate for EHV, tetanus, rotavirus
- move mare to yard intended for foaling between 2-6 weeks before foaling
- exercise mare regularly
- move to suitable space when parturition is imminent
- remove caslicks sutures once stage 1 of labour commences
why should mares be moved to yard intended for foaling between 2-6 weeks?
- stress of moving resolves before parturition
- antibodies develop to foaling environment, passed through colostrum and feto-placenta unit
What is the recommended stable for parturition?
6 x 6-7m dimensions, non-slip flooring
What is the recommended outdoor environment for parturition?
clean, dry, beware of hazards
What is included in a foaling kit?
- scissors or knife
- calving ropes
- iodine/chlorhexidine
- enemas
- torch
- tail bandage
- long arm & sterile short gloves
- hibiscrub
- lube
- colostrum
What is the mean gestation length?
320-360 days. Mare gestation is extremely variable.
How to deal with prepubic tendon rupture?
- Late gestation: supportive slings needed
- Assistance in labour is necessary
- Beyond 340 days induction necessary
- Caesarean section (possibly followed
by humane destruction of mare) - Surgical repair may be possible
Can you breed a horse who had a prepubic tendon rupture again?
- if surgical repair successful, but beware future issues
- alternatively breed again by ET
You should avoid induction unless absolutely necessary - when would thus be?
High risk of foaling is highly likely:
- History of problematic foaling when life of mare or foal is threatened
- History or risk of red bag delivery (premature placental separation)
- History of uterine inertia causing delayed delivery
- Mare pelvic injury or deformity or history of peri-parturient colic
- Foal distress or any other life-threatening condition
What is the criteria for decision to induce?
- Colostrum in the udder
- Pelvic and cervical relaxation
- Foetus in normal position
- Foetus is mature
(not premature or dysmature)
What is a commonly used assessment method for deciding when induction should go ahead?
Mammary secretions - changes in milk composition nearer parturition.
How does Na, K & Ca concentrations in milk change approaching parturition?
- Ca plateaus approx 4 days before parturition.
- K > Na = mature foal
In Ousey et.al., 1984 scoring system for milk secretion, what score is induction deemed safe at?
> 35
What are the methods for induction?
Exogenous application of oxytocin and prostaglandin F2a - stimulate myometrium contractions
Why should you time induction with natural parturition?
- other hormones will be correct at the time of labour
- fall in progesterone
- foetal cortisol increases
What happens if you induce labour too early & progesterone is too high?
Conflict in hormone profile - higher potential for problems
What does oxytocin administration do and when should you use it?
- stimulates prostaglandin F2a secretion from uterus
- use from 300 days gestation onwards
What are the administration options for oxytocin?
- 40-60 IU in 1 lt saline given intravenously (IV) over 15 min
- 5 -10 IU given IV in mares close to term repeat as necessary
- 10-15 IU given IV or IM every 30 min until water bag ruptures (max dose 75 IU).
How do we administer prostaglandin?
- use analogs
- most require single dose, dose dependent on analog use
why do we use prostaglandin analogs and not natural?
natural almost has no effect in inducing labour.
what are the types of prostaglandin analogs - dosage and results?
Fenprostalene requires 2 x doses, 2 hours apart
- Induces very rapid, strong contractions
Equimate (fluprostenol) single doses
- shorten stage 1 labour, does not start it
What are the risks of shortening stage 1 of labour with equimate?
incomplete dilation of cervix
- risk of cervix rupture
- neonatal adaptation issues
- fractured ribs of foal
How can you encourage cervix to dilate in induced labour?
- progesterone topically applied to cervix
- oestradiol IM 24 hrs prior to induction
Why may you administer steroids if mare is going to be induced prematurely?
- help mature foals respiratory system, increases cortisol in circulatory system (Ousey et.al., 2011)
