Dystocia - large animals Flashcards
Define eutocia
normal parturition
Define prodrome in this context
the pre-parturient phase of paturition
What happens in stage 1 of parturition
Everything before foetal (stage 2) and placental expulsion (stage 3):
positioning of foetus
cervical dilation
exposure of foetal membranes through vulva with possible rupture
How long may stages 1, 2 and 3 last in the cow?
1 = 6 hours 2 = 0.5-4 hours (older versus younger cows) 3 = 6 hours
How long may stages 1, 2 and 3 last in the mare?
1 = 1-4 hours 2 = 0.1-0.5hours (older versus younger cows) 3 = 1-2 hours
How does the water bag/allantochorion help parturition?
loosens birth canal
How common is dystocia in the different species?
MARE: 1-2% ponies, 10% draught breeds COW : 3-4% dairy, higher for beef EWE: 2-3% DOE: 1-2% SOW: <1% in feral, high in brachycephalics
What are the 3 main causes of dystocia?
Maternal - expulsion and birth canal
Foetal - size and disposition
Foeto-maternal disproportion
Define achondroplasia
where the bones don’t grow to the normal size based on breed expectations.
Mutation in FGF-R gene.
Selectively encouraged in some breeds (Daschund, Welsh Corgi and Skye terrier)
Name 2 problems of maternal expulsion
Uterine inertia - primary, secondary
Straining - defective, inadequate
Name 2 problems of the birth canal
Failure of relaxation or uterine torsion
Inadequate pelvic diamter
What history is important for dystocia cases?
Full term/overdue/premature? Primi or multigravida? Problems during pregnanct? When did straining begin? Water bag? Foetal fluids? Foetus? What has been done so far?
What should you examine for in the general dam check?
Status? (e.g. acidotic)
Exhausted
Milk fever?
Ill?
How does dystocia affect endometritis risk?
increases it 5 times
How is the dam usually positioned for parturition?
Standing - cow, mare, ewe
Lying - sow
What should you check in the specific examination?
VULVA/ VAGINA/ CERVIX: dilation, injury, lubrication
FOETUS: presentation, posture, position, number/structure alive/dead, size in relation to dam
What do you do in dystocia cases with a dead calf?
Foetotomy
How can you give anaesthesia?
None Epidural Paravertebral Inverted L Line block General
How much traction force does a person, calving jack, pulley and tractor have?
Person - 75kg
Calving jack - 400kg
Pulleys - 450kg
Tractor - 3000kg +
When should one/two people apply traction?
Carpal joint 10cm outside cow with 2 persons pulling - it should fit
Double-muscled calf - one person pulling
Coordinate pulling and staining
Once head is born, rotate calf 90 degrees and change pulling direction dorsally
What should you do in caudal presentations?
Manually dilate vulva/vagina
Check umbilical cord
Hock joint 10cm outside cow with 2 persons pulling - should fit, then deliver ASAP
Pull dorsally
What are the 3 aspects of foetal disposition?
Presentation
Position
Posture
Define presentation
Relationship between longitudinal axis of foetus and dam and the portion of the foetus entering the birth canal (longitudinal/normal anterior, longitudinal posterior, transverse)
Define position
Relationship between the dorsal surface of the foetus (vertebral column) and the surface of the maternal birth canal (dorsal/normal, ventral or lateral)
Define posture
The disposition of the movable appendages of the foetus (limb flexions, neck flexions, head displacements)
List reasons for incorrect disposition - 5
weak uterine contractions delayed development of foetal reflexes weak foetal movements competition for uterine space/oversized calf joint ankylosis
Outline dystocia aftercare
DAM - main concern - trauma, ABs, oxytocin (exogenous or endogenous), NSAIDs
NEONATE - dip navel, colostrum supply
What happens in stage 2 of parturition?
Uterine contractions intensify
Abdominal pressing by dam
Expulsion of foetus
What is another name for stage 3 of parturition?
the ‘cleaning’ stage
