Clinical Examination of Farm Animals - CYF MEDICAL DISTRIBUTION

Clinical Examination of the Gastrointestinal System
examination is usually limited to cattle over 12
months of age and, to avoid creating a pneumorectum
and tenesmus which may confuse abdominal
auscultation and percussion, is the last part of the
clinical examination.
Rectal examination of the gastrointestinal tract can
be used to detect a viscus which is displaced or enlarged.
The rectal examination is particularly useful
in palpating a grossly distended rumen, caecal dilatation
and torsion, gut tie, and intestinal intussusception.
The gas or fluid content of the abnormal viscus
can be assessed. Indicators of peritonitis such as adhesions
and a sandy grating sensation may be palpable.
The quantity and composition of the faeces can
be assessed.
Method
Examination per rectum requires care and patience
with good restraint. It is best performed in the
standing animal, although it is possible in the recumbent
animal. In the recumbent animal the
abdominal contents are displaced caudally, which
makes palpation difficult unless the animal is placed
in lateral recumbency. The safety of the operator
should be considered if the animal is likely to
rise. Fingernails should be short and well manicured;
watches and rings should be removed; the gloved
hand should be well lubricated. The tail has to be elevated
to enable access to the rectum. It is likely that a
rectal prolapse will have been detected before this
point in the examination, either by observation or by
the presence of tenesmus. However, on raising the
tail a rectal prolapse will present with inflamed oedematous
rectal mucosa protruding through the anus.
The rectal examination proceeds by coning the fingers
and gently pushing through the anal sphincter.
Sometimes a small rotatory movement of the hand
helps to facilitate entry. Palpation is performed with
the open hand. If the rectum is full of faeces, manual
evacuation of the faeces will be required. This must
be done slowly and carefully to avoid the entry of air
into the rectum. If air is allowed to enter the rectum
the wall may balloon and make palpation of internal
structures impossible. Gentle backwards stroking of
the ventral rectal mucosa may facilitate a peristaltic
wave which may decompress the rectum so that
palpation can continue. Peristaltic waves should be
allowed to pass over the arm and active palpation
suspended. If blood is seen on the glove, bleeding of
the mucosa may be suggested and the examination
should be curtailed.
The rectal examination
The contents of the posterior abdomen should be
checked in a set order to avoid missing any organ. The
examination area may be divided into quadrants or
conducted by body system. Alternatively, a combination
of both approaches can be used. Each quadrant
examination area is palpated and the organs present
assesed or noted if unexpectedly absent. Under normal
conditions the omasum, abomasum and liver
cannot be felt. Parts of the small intestine and large
intestine can be felt but are not discrete structures.
In the normal animal it is possible to palpate the
caudal surface of the dorsal sac of the rumen to the
left of the pelvic brim. The degree of filling and nature
of the contents should be assessed. In vagal indigestion
the rumen is often packed with undigested
fibre. The absence of the dorsal sac usually indicates
a collapsed dorsal sac. A left displaced abomasum
cannot be felt per rectum unless the gas-filled viscus
is displaced very high and caudal in the left flank,
which is exceptional. A right displaced and/or
dilated abomasum may be felt at arm’s length laterally
on the right as a tense gas-filled viscus. Intussusceptions
usually occur at the ileocaecal junction. The
invagination of one part of the intestine into another
can sometimes be felt as a large hard sausage-like
structure on the right. A distended caecum can be
palpated on the right as a tense gas-filled sausageshaped
balloon with the blind end caudally. If displacement
has also occurred, the blind end of the
caecum may have been rotated cranially out of reach.
In gut tie a tense band may be felt ensnaring the intestine
on the right side. This is caused by peritoneal
adhesion of the remnant of the spermatic cord following
castration. Abdominal masses, such as the
large focal fat deposits in fat necrosis, may be palpated.
Thickening of the intestine may be detected in
Johne’s disease, but this is highly subjective. Nonspecific
referred pain or focal pain responses may be
elicited on rectal examination. Referred pain may
arise from a peritonitis or traumatic reticulitis. Focal
pain may be provoked on palpation of an intussus-
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