Eutocia/Dystocia

Question 1

What changes occur in the mother prepartum ?

Answer 1

Udder edema and milk production 1-2weeks prior (waxing)

Relaxation of pelvic ligaments > raised tail head (sacrosciatic and sacrotuberous ligaments)

Elongation and softening of the vulva

Dilation and opening of the cervix just prior to parturition

Melting of the cervical plug > appears at the vulva

Question 2

What are the mechanisms leading to parturition?

Answer 2

Maturation of fetal hypothalamic-hypophyseal-adrenal axis

Increased sensitivity of the fetal adrenal glands to ACTH

Increased fetal corticoids from adrenal cortex

Activation/conversion of placental enzyme systems
—decreasing progestagens
—increasing estrogen precursors and estrogens

Relaxin and prolactin

Uterine — up regulation of oxytocin receptors and release of prostaglandin F2a

Question 3

What is stage 1 of eutocia?

Answer 3

Initiation of myometrial contractions (initiated by fetus)

Usual duration 1-6hours

Question 4

Clinical signs of stage 1 of eutocia

Answer 4

Restlessness 
Anorexia 
Signs of abdominal discomfort 
Increased pulse and respiration 
Nesting/isolation form others
Shifting weight 
Arched back elevated tail 

Dilation of cervix

Question 5

Where do contractions begin in a monotocous or polytocous species?

Answer 5

Monotocous — apex of the pregnant horn

Polytocous — cranial to most caudal fetus

Question 6

“Breaking water” is a rupture of the _______________ membrane

Answer 6

Chorioallantoic

Question 7

What occurs in stage 2 of parturition?

Answer 7

Delivery of fetus

Begins with rupture of chorioallantois

30-60mintues
Active straining/abdominal press

Rupture of the amnion
Ferguson’s reflex

Dam lies in sternal recumbency then lateral for delivery

Question 8

What is Ferguson’s reflex?

Answer 8

Wedging of fetus into cervical canal stimulates oxytocin release, which stimulates more uterine contractions

Question 9

What is stage 3 of parturition ?

Answer 9

Expulsion of fetal membranes

Question 10

What 3 P’s are used to describe the position of the fetus at parturition?

Answer 10

Presentation — relationship of the spinal axis of the fetus to that of the dam and the portion of the fetus that is entering the birth canal (longitudinal/transverse)

Position — anatomic relationship of the dorsum of the fetus relative to maternal pelvis (dorsal-sacral/dorsal-pubic/dorsal-ilial)

Posture — anatomic relationship of the fetal extremities to its own body (flexed/extended/retained)

Question 11

What is dystocia?

Answer 11

Abnormal or abnormally difficult birth

More common amoung primiparous than multiparous (cattle greatest risk, cats lowest risk)

Question 12

What are maternal causes of dystocia?

Answer 12

Primary uterine inertia — never progress to stage two, weak abdominal contractions, cervix usually dilated on exam

Secondary uterine inertia — exhaustion of myometrium after prolonged attempts to deliver fetus

Abnormalities of birth canal
— inadequate size of pelvis, pelvic deformities, incomplete cervical dilation, neoplasms, persistant Müllerian ducts

Question 13

What are fetal causes of dystocia?

Answer 13

Abnormal presentation, position, and posture

Fetal monsters

Fetal oversize

Question 14

What is a rare congenital anomaly where there is complete/partial agenesis of lumbar, sacral, or coccygeal vertebrae? Usually results in arthrogryposis of the hindlimbs and malformation of the musculature.

Answer 14

Peresomus elumbus

Question 15

What do you call the congenital abnormality where there is failure of the body wall to close, resulting in an “inside-out” calf with external abdominal organs?

Answer 15

Shistosomus reflexus

Question 16

What is usually the cause of fetopelvic dysporoportion?

Answer 16

Management related

Eg.
insufficient nutrition —> insufficient maternal growth

Excessive nutrition during later gestation —> rapid fetal growth

Question 17

What traumatic conditions can lead to dystocia?

Answer 17

Herniation or rupture of the prepubic tendon may disallow abdominal press

Torsion of the uterus creates mechanical stress of tubular tract

Fractures of the pelvis - if not healed in apposition, may reduce size of bony pelvic canal

Question 18

What type of history do you want to get in a dystocia?

Answer 18

Length of problem

Who has attempted deliver

Question 19

A heifer presents for a dystocia. You are going to do a vaginal exam to look for???

Answer 19

Tears 
Fibrosis 
Dilatation 
Elasticity 
Lubrication

Question 20

To do a vaginal exam, how are you going to prepare the area?

Answer 20

Wash vulva and perineum with warm water and mild antiseptic solution (eg dilute iodine)

Question 21

When examining the fetus, how can you determine if it is alive?

Answer 21

Positive response to pedal, palpebral, eyeball,, mouth and anal pressure by movement reflex

Excessive movement of extremities or tongue may indicate hypoxia

Question 22

What do you call the process by which the fetus is restored to deliverable fashion?

Answer 22

Mutation

Question 23

What do you call pushing the fetus out of the maternal pelvisinto the uterine cavity to enable correction of an abnormality?

Answer 23

Repulsion

Question 24

What do you call turning the fetus on its longitudinal axis?

Answer 24

Rotation

Question 25

Why out would you want to use OB lube over J lube?

Answer 25

J lube is damaging to abdomen if there is leakage, dont use this if there is a possibility you might need to do a C-section

Question 26

Calves are born with what additional layer over their hooves?

Answer 26

Eponychium

Question 27

When is fetal extraction appropriate?

Answer 27

Only after mutations are completed and the fetus is in favorable position and deliverable size-wise

Question 28

What are options for fetal extraction?

Answer 28

Hand delivery — no more than 2 adults on chains

Calf jack — ratchet caudally until there is tensions

Always use lube!

Question 29

What can occur if you have traction on both forelimbs simultaneously ? How can this be fixed?

Answer 29

Shoulder lock

Apply traction to one forelimb while relaxing on the other

Question 30

What can you do if the dystocia is caused by failure of the vulva to dilate ?

Answer 30

Manual stretching

Episiotomy

Question 31

How can you prevent hip lock during fetal extraction?

Answer 31

Rotate calf as head everted

Question 32

How can you removed a dead calf?

Answer 32

Fetotomy