Eutocia, Induction of Parturition Flashcards
What are 4 things that should be done 4-6 weeks prior to foaling?
- Vaccinate
- watch more frequently
- Clean udder and legs
Open Caslicks if present
What are 4 recommended vaccinations for the pregnant mare for?
- EWT
- WNV
- EHV 1
- EHV 4
What can result if a Caslick is not removed prior to parturition?
Recto-vaginal fistula/tear
What are the 3 best predictors for readiness for birth in the mare?
- Udder formation with the presence of colostrum
- Relaxation of cervix
- Gestational age greater than 330 days
What are 5 signs that parturition might be occurring soon?
- External conformation
- Udder development 2-4 weeks prior
- Cervical relaxation
- Milk calcium test kit/strips
- Milk electrolyte inversion
What are 3 signs of udder development to watch for?
- Milk in teats 1-2 weeks prior
- Waxing 24-48 hours prior
- Dripping of milk
Is minor separation of the vulva normal close to parturition?
Yes
Cervical dilation favors what?
Shorter delivery time
What are 4 things that might be seen with an unrelaxed cervix?
- Longer time from induction to delivery
- Possible increase in intra-partum asphyxia
- Longer time to stand and nurse
- More complications such as placental separation and dystocia
What are 3 things to watch for with milk composition?
- Inversion of Na+ and K+
- Increase in Ca++
- Changes in color/viscosity
Inversion of sodium and potassium indicates what?
Within 48 hours of parturition
“Foal Watch” should be used once a day until how many ppm are reached?
Then what?
- 125 ppm
- Then test 2x per day
The best clinical use of the milk pH test is to predict what?
When a mare is NOT ready to foal.
Does pH increase or decrease near foaling?
Decreases
What type of mares may not have significant development or colostrum production?
Maiden mares
Restlessness, tail swishing, mild colic, sweating, fetus re-orients itself and cervix dilation can be seen with what stage of parturition?
Stage 1
Mare gets up and down, forceful abdominal contractions occur, appearance of amnion covered fetal limbs at vulva can be seen with what stage of parturition?
Stage 2
Mild colic signs can be seen with what stage of parturition?
Stage 3
Stage 1 of parturition ends with what?
Ends with rupture of chorioallantois
Stage 2 of parturition ends with what?
Ends with expulsion of fetus
Stage 3 of parturition ends with what?
Ends with passage of placenta
What are 5 things that should be done with the mare post-foaling?
- Examine for twin
- Examine for any trauma
- Assess udder
- Assess significance of any colic signs
- Make sure placenta is expelled by about 3 hours
A mare is considered to have retained fetal membranes if the placenta has not been expelled by what time frame?
3 hours post-foaling
What are 3 reasons for performing induction in a mare?
- Gestational abnormalities
- Mare with previous dystocia or history of placental separation
- Convenience
What are 2 examples of gestational abnormalities that would indicate the use of induction?
- Rupture of pre-pubic tendon
- Hydrallantois
What are 4 complications that can be seen with the induction of parturition?
- Dystocia
- Premature placental separation
- Fetal hypoxia
- Dysmaturity
Fetal maturation is associated with what?
Increased adrenocortical activity
When does increased adrenocoritcal activity occur in most species?
When does it occur in horses?
- A few weeks prior to birth
- 24-48 hours before birth
The foal needs to be what before the mare can be induced?
Foal needs to be mature
An equine fetus is at much greater risk of what if delivered at an inappropriate time?
Dysmaturity/prematurity
What are 6 things a foal needs in order to survive?
- Functional lungs
- Functional GI
- Appropriate energy reserves
- Ability to suck
- Ability to swallow
- Ability to maintain body temperature
Oxytocin is released from the posterior pituitary secondary to what?
Ferguson’s reflex
What are 2 important stimulants to myometrial contraction?
- PGF2a
- Oxytocin
Are steroids usually used as an induction agent in horses?
Why?
- No
- Need high doses and prolonged treatment to be successful
How long does it take for prostaglandin to induce parturition?
1-6 hours
Prostaglandins may be useful in pre-treatment prior to what?
Oxytocin
What are 2 side effects that can be seen with prostaglandin use at higher doses?
- Sweating
- Mild colic
What is the induction DOC in mares?
Oxytocin
Foaling occurs within what time frame with oxytocin use?
Within 60 minutes
What is the typical dose of oxytocin used to induce parturition?
10-20 IU IM once
A higher dose of oxytocin may cause what?
Discomfort
Which layer should be presented at he vulva?
Amnion
If everything is going well, one should wait until what occurs before intervening?
Wait until umbilicus breaks
A foal should be standing by when?
Nursing by when?
- Standing within 1 hour
- Nursing within 2 hours
How does a placenta often present after delivery?
Often turned inside out after delivery.
When spread out, the placenta should form what shape?
Y or F shape
What should be examined in the placenta?
Both allantoic and chorionic surfaces
What is the normal umbilical cord length in a horse?
36-83 cm
An umbilical cord weighing more than 12.5 lb. may be associated with what?
Associated with problems
What is the normal weight of an umbilical cord?
About 11% of foal’s weight
What are 2 things that make the fetus susceptible to torsion of the umbilical cord and to amnion covering the nostrils at birth?
- Length of umbilical cord
- Non-union of amnion to chorioallantois
What are 2 things that can occur if the umbilical cord is too long?
- Hypoperfusion
- Wrapping around extremities
What are 2 things that can happen in the umbilical cord is too short?
- Premature placental separation
- Breaking of the cord
Umbilical cord torsion has a greater chance if the cord is greater than what length?
Greater than 80 cm
What are 3 things that can be seen with an umbilical cord torsion?
- Area of demarcation
- Compression of urachus
- Degenerative changes to chorioallantois
Compression of the urachus as a result of umbilical cord torsion can lead to what?
Bladder distention
What are 4 degenerative changes to the chorioallantois that can be seen with umbilical cord torsion?
- Mineralization
- Vascular congestion
- Hemorrhage
- Thrombosis
What is something that can be seen with a normal foal but an abnormally long umbilical cord?
Why?
- Twisted umbilicus
- Excessive movement of normal foal can cause this
What can happen to a yolk sac remnant?
Some become calcified
Are lesions common on the amnion?
No
Thickened cystic nodular areas can be seen with what condition?
Amnion nodosum
How can too little amniotic fluid lead to amnion nodosum?
Fetus rubs on inner epithelial amnionic surface
Hair and sebaceous material embedding in focally ulcerated amnion causing chronic proliferative changes can lead to what condition?
Amnion nodosum
What is a possible inciting cause for amnion nodosum?
Primary urinary system problems in the foal.
Concentric to diffuse firm whitish colored lesions that seem to radiate from blood vessels but are not associated with vascular changes are called what?
Enigmatic localized mineralization
Are enigmatic localized mineralizations usually related to infectious placentitis?
No
What does enigmatic localized mineralization resemble?
“Lichen growing on dead wood”
