Clinical Examination of Farm Animals - CYF MEDICAL DISTRIBUTION

CHAPTER 5
pneumonia gentle palpation of the trachea may produce
paroxysmal coughing (Fig. 5.21). Increased tracheal
sounds may be heard on auscultation.
Oesophagus
The muscular and softer oesophagus is less readily
identified than the trachea as it passes down the ventrolateral
neck. In normal animals with fine coats boluses
of food can be seen in it passing down to the
rumen. Boluses of cud pass up and down during rumenation.
Eructation of gas can occasionally be seen
and often heard as it passes up into the pharynx. Difficulty
in swallowing – dysphagia – may occur if there
is an inflammatory lesion in the pharynx or if the
retropharyngeal lymph nodes are enlarged. The oesophagus
may be obstructed by tumour masses in
the mediastinum and heart base tumours.
Dilation and malfunction of the distal oesophagus
may be caused as a result of malfunction of the
10th cranial (vagus) nerve. Rupture of the oesophagus
may occur through careless administration of anthelmintic
boluses. Dysphagia and local swelling
around the injury are seen. Further investigation by
endoscopy and contrast radiography can be used to
confirm the presence of a penetrating injury.
Jugular vein
The jugular vein is readily visible in the jugular furrow
on both sides of the neck. In healthy animals the
vein should not be distended unless venous return is
obstructed by manual pressure on the vein lower
down the neck or in cases of right sided heart failure.
For further evaluation see Chapter 6.
Clinical signs and diagnosis of choke
in cattle
Obstruction of the oesophagus by a foreign body is
termed ‘choke’ in cattle and usually occurs when cattle
are eating unchopped root crops such as carrots
and potatoes. The foreign body may lodge anywhere
along the length of the oesophagus, but common
sites include the pharynx, the thoracic inlet and over
the base of the heart.
Initial signs of choke include discomfort, profuse
salivation, coughing up of saliva and the development
of rumenal bloat. Pharyngeal foreign bodies
can sometimes be palpated externally and their presence
confirmed by manual palpation of the pharynx
with the clinician’s hand advanced through the
mouth of the gagged animal. Foreign bodies may be
palpable within the cervical part of the oesophagus
whilst those lower down may be located by careful
passage of a stomach tube.
The tube is passed through the ventral meatus of
the nose and into the oesophagus (Fig. 5.22). Its
passage to the rumen is halted by the foreign body
but in some cases it can be carefully pushed on into
the rumen. The position of the obstruction can be
determined by comparing the length of stomach
tube which has passed into the oesophagus to the
point of obstruction with the route of the oesophagus
pictured outside the animal’s body.
CLINICIAN’S CHECKLIST – THE NECK
Mobility
Soft tissue swellings
Larynx – external palpation
Pharynx – external palpation
Retropharyngeal lymph nodes
Trachea – auscultation and compression
Jugular vein – initial assessment
CLINICIAN’S CHECKLIST – CLINICAL
SIGNS OF CHOKE IN CATTLE
Exposure to root crops
Unsuccessful attempts to swallow
Profuse salivation
Coughing up saliva
Distension of the rumen
Obstruction palpated in pharynx
Obstruction located by stomach tube
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