Eutocia and Dystocia Flashcards
What are 5 major prepartum changes?
Udder edema and milk production Relaxation of pelvic ligaments Elongation and softening of the vulva Dilation and opening of the cervix Melting of the cervical plug
What does the term “springers” refer to?
Relaxation of the pelvic ligaments makes the animals a bit more “bouncy” in the back end.
What does the term “waxing” refer to?
Udder edema and milk production.
What is the main signal for parturition?
Fetal stress causing release of fetal cortisol
What uterine activity do we see during parturition?
Upregulation of oxytocin receptors.
What are the 3 stages of Eutocia?
Initiation of myometrial contractions
Expulsion of the fetus
Expulsion of fetal membranes
What stage of eutocia do we worry about most in horses?
Stage 3, expulsion of fetal membranes
What initiates stage 1 of parturition?
The fetus
What is the duration of stage 1 of parturition?
1-6 hours
What happens during stage 1 of parturition?
Cervix dilates
During what stage of parturition does colostrum/milk become available in the teats?
Stage 1
What does “dropping” mean?
Availability of colostrum/milk in the teats
During what stage of parturition does rotation of the fetus occur?
Stage 1
Where do contractions start during phase 1 of parturition?
Behind the most distal fetus.
What happens during state 2 of parturition?
The fetus is delivered.
How long does stage 2 of parturition typically take?
30-60 minutes
NOTE: Heifers may be up to 4 hours
NOTE: Multiparous species may be shorter
What is the Ferguson’s reflex?
Really strong contractions
What membrane ruptures during stage 1 of parturition?
Chorioallantoic membrane (“water”)
What membrane ruptures during stage 2 of parturition?
Amnion. Helps provide some lubrication.
What initiates the Ferguson’s reflex?
Wedging of the fetus into the cervical canal
What occurs during stage 3 of parturition?
Expulsion of fetal membranes
In what species is a retained placenta very important to correct?
Equine
What is the general rule of thumb for parturition duration?
1 hr for birth
2 hr for standing
3 hr for sucking
What does eutocia mean?
Normal delivery
What are the 3 P’s of eutocia?
Presentation
Position
Posture
What does presentation refer to?
Spinal axis of the fetus to that of the dam and the portion of the fetus that is entering the birth canal.
EG: longitudinal (cranial or caudal) vs. transverse (ventral or dorsal)
What does position refer to?
Anatomic relationship of the dorsum of the fetus relative to the maternal pelvis.
EG. dosro-sacral/dorso-pubic/dorso-ilial
What does posture refer to?
Anatomic relationship of the fetal extremities to its own body.
EG: describing the limbs coming at you… flexed, extended, retained
What is dystocia?
Abnormal or abnormally difficult birth
What species is at most risk of dystocia?
Cattle
What species is at the least risk of dystocia?
Cats
What kind of damage can horses do during labor?
They can push with so much force that they can rupture their uterus.
What are 3 maternal causes of dystocia?
Primary uterine inertia
Secondary uterine inertia
Abnormalities of the birth canal
What is primary uterine inertia?
Contractions are not happening for some reason.
What is secondary uterine inertia?
Depleted energy and can’t push anymore
What are 3 fetal causes of dystocia?
Abnormal presentation, position and posture
Fetal monsters
Fetal oversize (babies are just too big, shouldn’t have bred that dam and sire together so more the producer’s fault)
In what breed is it common to see fetopelvic dysproportion resulting in 100% C-sections?
Belgian blue
In what 2 ways can insufficient nutrition cause dystocia?
Insufficient maternal growth
Insufficient or imbalanced rations (eg. hypocalcemia) lead to uterine inertia
In what 2 ways can excessive nutrition cause dystocia?
Obesity may impede the passage of a fetus trough the pelvis
Abnormally rapid fetal growth
What are 3 other causes of dystocia?
Management
Infectious conditions
Traumatic conditions
What are 3 ways management can cause dystocia?
Stress
Insufficient age at breeding, growth or both
Restricted exercise leading to uterine inertia
How can infectious conditions cause dystocia?
Infections may be tocolytic (anti-contraction) or infections of the fetus may cause weakness or death predispose to postural abnormalities.
What are 4 traumatic conditions that can cause dystocia?
Torsions
Herniations
Ruptures
Pelvic fractures
