WildLife Group
of the SAVA
West Nile Virus in particular and Middelburg Virus to
a lesser extent, may reach high levels in the central
nervous system and so pose a significant zoonotic risk
during the removal of the brain and spinal cord.
External Examination of The Fetus
•
Evaluate for any evidence of congenital
abnormalities (chondrodysplastic dwarfism,
hydrocephalus, cleft palate, ectopia cordis
etc) especially in breeding facilities (where
parentage identification is possible), allowing for
identification of potential problematic genetic
lines.
•
Examine for features of foetal oversize/dystocia
such as facial swelling, swollen tongue and
subcutaneous edema / bruising. Such features are
frequently accompanied by meconium staining,
because of foetal stress.
External examination of the placenta
•
•
•
Wash off any soiling on the placenta so that it
can be closely inspected for any evidence of
placentitis, necrosis, oedema and congestion/
haemorrhage. Remember placentitis and/or
necrosis maybe regional.
Evaluate the placenta for any evidence of meconial
staining.
Determine if the placenta is complete or
incomplete, an if incomplete this could indicate a
retained placenta in the dam.
Morphometric measurements
The morphometric measurements collected are used to
establish foetal age, and whether there is any evidence
of stunted foetal growth or placental insufficiency. The
parameters that that should be measured include
Figure 1: Sable antelope foetus with heart exteriorised from the
thoracic cavity (arrow) - ectopia cordis.
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•
•
•
10
Examine for meconium staining which indicates
a distressed foetus and is an important indicator
lesion for foetal hypoxia.
Evaluate mucous membranes for any signs of
anaemia and/or icterus (neonatal theileriosis
in sable and roan antelope, biliary atresia sable
antelope, neonatal piroplasmosis in giraffe).
Angulated limb abnormalities (in-utero viral
infection, prussic acid poisoning, micronutrient
imbalances).
Age-appropriate features - external characteristics
(hair coat cover, eyelid separation, tooth eruption
etc) are matched to foetal age. In-appropriate
features for gestational age, indicate retarded
foetal growth.
•
•
•
•
Foetal weight.
Crown-rump length.
Placenta weight.
Cotyledon number, average cotyledon diameter
and average cotyledon weight. These parameters
are closely correlated to placental efficiency and
foetal growth.
Dr Benirschke’s Comparative Placentation site http://
placentation.ucsd.edu/homefs.html is an exhaustive
resource that provides a wealth of information on
foetal weights, crown rump lengths, gestational length,
placental weight and cotyledon diameter for many of
our African wildlife species. This reference material
will enable you to make informed decisions about the
significance of the morphometric measurements that
you collect.
Gross features which would indicate that a foetus
was alive at expulsion include loss of intact “slippers”
covering the hooves and umbilical artery haemorrhage.