Clinical Examination of Farm Animals - CYF MEDICAL DISTRIBUTION

Clinical Examination of the Lymphatic System
Parotid lymph node
Precrural lymph node
Retropharyngeal
lymph node
Supramammary
lymph node
Submandibular lymph
node
Clinician's hand lifting
udder to facilitate palpation of
supramammary lymph node
Prescapular lymph node
Figure 3.1 Locations of the readily palpable lymph nodes in cattle showing placement of the clinician’s hand. See text for details.
Submandibular lymph nodes
These are situated and are palpable on the medial
aspect of the ‘angle of the jaw’ where the horizontal
and vertical rami of the mandible meet. Normal size
is 1.5 to 2 cm at maximum diameter.
Parotid lymph nodes
Often these are not palpable unless they are enlarged
through local infection or tumour formation. These
small nodes lie subcutaneously just below the temperomandibular
joint. Normal size is 0.5 cm.
Retropharyngeal lymph nodes
These nodes lie in the midline dorsal to the pharynx.
If enlarged they can be palpated by placing two
fingers of one hand on either side of the larynx. The
fingers of the two hands are advanced towards each
other just dorsal to the larynx. In normal animals the
retropharyngeal nodes are rarely palpable and it is
possible to advance the fingers (as described above)
towards each other until they are separated only
by the compressed pharynx. Dysphagia and dyspnoea
with stertorous breathing may be seen in
animals in which the retropharyngeal nodes are enlarged.
The nodes may be up to 4 cm in diameter
when enlarged.
Prescapular lymph nodes
These nodes lie subcutaneously and underneath the
cutaneous muscle just anterior to the shoulder joint.
It is often possible to palpate them directly in front
of the shoulder. They may also be reliably located by
extending the fingers and pressing them forward
from the shoulder joint onto the neck. The fingers
push against the prescapular node even if it is small,
thus identifying its position. Further advance causes
the fingers to rise over the node and down onto the
neck in front of it, thus obtaining an estimate of
the size of the node. The prescapular nodes vary in
size and may be small and round or elongated in
a dorsoventral direction. Normal size in adult is
1cm¥ 3.5 cm.
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