Page 575 - The Veterinary Laboratory and Field Manual 3rd Edition

512 Samuel Sharpe

• Using a flat-headed screwdriver or chisel
lever the skull cap up and expose the menin-
ges covering the cerebral hemispheres and
cerebellum.
• Incise the dura mater and dissect away from
the underlying brain.
• To remove the brain from the skull: tilt the
skull backwards as the brain will be freed
from front to back. Beginning at the rostral
part of the brain cut through the olfactory
bulbs. Moving along the ventral surface cut
the optic nerves at the chiasm and continue
to work ventrally and laterally to sever the
Figure A2.3 Removing the brain. Arrows delineate
the direction of the first two slightly divergent cuts other cranial nerves.
just inside the occipital condyle. See also Online
figure 2. SaMPLInG
• The brain should NOT be bread loafed prior
to formalin fixation.
• If the brain is to be submitted for histopathol-
ogy it should be immersion fixed in a large
volume of formalin, usually in a container
separate to other histological samples.
• If fresh brain is required for ancillary testing,
make a sagittal cut between the hemispheres
of the cortex to bisect the brain along its
length. Half of the brain should be fixed
and half should be retained frozen. This will
ensure all brain areas are represented in both
samples.

Opening limb joints
• It is always advisable to open and assess at
least three joints during necropsy.
• This is particularly important in neonates in
Figure A2.4 Removing the brain. Arrows delineate which septic arthritis is a common manifesta-
the direction of the remaining cuts, the first through tion of septicaemia.
the frontal bones at the level of the bone just cau- • Specific technique will vary between joints
dal to the zygomatic process of the frontal bone. depending on anatomy but in general the
Following this, two sagittal cuts are made bilater- overlying area should be skinned and sub-
ally through the occipital, parietal, and frontal bones cutaneous tissues and muscle should be
joining up the cuts in the occipital bone and frontal removed to facilitate identification of the
bones. See also Online figure 3. joint space. Using the point of the knife incise
the joint capsule and collateral ligaments on

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