Transcript Meeting December 1, 2006

Dystocia : Causes,
Treatment and Prevention
ผศ. ชัยวัฒน์ จรัสแสง
References
Arthur’s Veterinary Reproduction
and Obstetrics : Noakes, D.E.,
Parkinson, T.J. and England,
G.C.W. 8 th edition (2001)
 Handbook of Veterinary
Obstetrics : Jankson, P.G.G. 2 th
(2004)
 The technique of Fetotomy in
Large Animals : Bierschwat, C.J.
and deBois, C.H.W.

Dystocia : consequences and
cost of dystocia
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Increased stillbirth rate mortality
Increased neonatal morbidity
Increased mortality rate for the dam
Reduced productivity of the dam
Reduced subsequent fertility and
increased chance of sterility
Increased likelihood of puerperal
disease in the dam
Increased likelihood of culling
The stages of birth
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First stage
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Second stage
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Relaxation and dilation of cervix
Fetus adopts birth posture
Uterine contraction
Chorioallantois enters vagina
Uterine contraction continues
Fetal enters birth canal
Abdominal contraction
Amnion enters vagina
Fetus expelled
Third stage
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Placenta expelled
Causes of dystocia
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Maternal causes
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Failure of explosive forces
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Obstruction of birth canal
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Uterine
Abdominal
Bony pelvis
Soft tissue
Fetal causes
Uterine failure of explosive
forces
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Uterine
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Primary uterine inertia
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Myometrial defects
Biochemical deficiencies
Hysteria/environmental disturbance
Oligoamnion
Premature birth
Secondary uterine inertia
Uterine damage or rupture
Uterine torsion
Abdominal
Obstruction of the birth canal
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Bony pelvis
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Fracture, breed, diet, immaturity,
neoplasm, diseases
Soft tissue
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Vulva : congenital, fibrosis, immaturity
Vagina : congenial, fibrosis, prolapsed,
neoplasia, abscess, hymen
Cervix : congenital, fibrosis, failure to
dilate
Uterus : torsion, deviation, herniation
Fetal causes
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Hormone deficiencies
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Fetopelvic disproportion
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Fetal oversize
Fetal monster
Fetal maldisposition
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ACTH/ cortisal
Malpresentation
Malposition
Malposture
Fetal death
Fetal terminology
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Presentation
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Position
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The relationship between the long axis
of the fetal and the long axis of the birth
canal. (anterior, posterior, transverse,
vertical)
Surface of the maternal birth canal to
which the fetal vertebral column.
(dorsal, ventral, lateral)
Posture
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The position of the head and limbs of
the fetus.
Dystocia in the cow
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Incidence 3-10 %
Environmental factors
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Diet, supervision, disease, Induction of
birth
Intrinsic factor
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Age, parity, body weight, pelvic size
Breed
Calf weight, sex and size
Gestation length
Sire effect
Calf presentation
Causes of dystocia in the cow
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Fetopelvic disproportion
Fetal malpresentation
Failure of cervix and
vagina to dilate
Uterine inertia
Uterine torsion
Maternal abnormalities
Fetal abnormalities
45 %
26 %
9%
5%
3%
7%
5%
Failure of the explosive forces
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Uterine inertia
Premature birth
Failure of abdominal expulsive
forces
Uterine rupture
Uterine torsion
Obstruction of the birth canal
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The bony pelvis
The soft tissues
Torsion of the uterus
Downward deviation of the
uterus
Fetopelvic disproportion
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Fetal monster
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Conjoined twins
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Dicephalus
Siamnese twins
Shistosomus reflexus
Bulldog calf
Perosomus elumbis
Hydropcephalus
Fetal anasarca
Fetal ascites
Fetal maldisposition
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Malpresentaion
Posterior presentation
 Transverse presentation
 Vertical presentation
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Malposition
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Ventral position, lateral position
Fetal maldisposition
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Malposture
Lateral deviation of the head
 Downward deviation of the head
 Retention of a forelimb
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Carpal flexion
 Shoulder flexion
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Retention of hindlimb
Hock flexion
 Hip flexion
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Approach to a case of
dystocia in the cow
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Assistance required
Restraint of the patient
Sedation
Uterine relaxation
Epidural anesthsia
Equipment
Case history
General clinical examination
Vink Jack
HK calf puller
Vaginal examination
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Examination of the fetus
Evidence of fetal life
 Evidence of fetal death
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Manipulative delivery
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Is vaginal delivery likely to be
possible and successful?
Comparison of the size of the
fetus and birth canal
Treatments
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Mutation and force extraction
Caesarian section
Fetotomy
Mutation and force extraction
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Retropulsion
Rotation  longitudinal axis
Version  transverse axis
Extension and Adjustment of the
extremities
Traction
Hock flexion
Mutation and force extraction
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Repulsion of the proximal
portion of the extremity
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Lateral rotation of the huddle
portion of the extremity
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Traction on the distal portion of
the extremity
Forced Extraction
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Retraction from out-site
Mutation already
Caution
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Disposition
Oversize
Small birth canal
Uterine inertia
Cervix no dilate
Paralysis obturator nerve
Severe vulva tear