Clinical Examination of Farm Animals - CYF MEDICAL DISTRIBUTION

Clinical Examination of the Gastrointestinal System
Examination of the environment
Sudden access to legume-rich pastures may result in
frothy bloat. Breaking into maize fields, food stores
or orchards may be related to an outbreak of ruminal
acidosis.
Mouldy feed may contain mycotoxins. Overcrowding
and floor feeeding are associated with outbreaks
of coccidiosis in growing animals.
Observations at a distance
Behavioural manifestations of abdominal pain include
kicking at the abdomen, reluctance to get up
and down, and movements made with care. Grunting
may be audible. Animals may adopt abnormal
postures such as lowering the back and stretching the
forelegs forwards and the hind legs backwards. This
is called the rocking horse posture and is seen with
intussception. Grinding of teeth or bruxism may be
observed. The animal may appear depressed. Straining
in attempts to defaecate (rectal tenesmus) may be
apparent and can be confused with urinary tenesmus.
The rate of eructation, regurgitation and cudding
may be reduced. In chronic conditions there
may be a low body condition score and loss of
weight. Dropping of the cud may indicate pathology
of the cardia. Ruminal tympany may cause dyspnoea.
Sunken eyes may indicate dehydration or
cachexia. An increased respiratory rate may indicate
compensation of a metabolic acidosis. Recumbency
may occur due to weakness or pain. Appetite may be
reduced or there may be anorexia. There may be a reduction
in the quantity and a change in the composition
of the faeces. The production and passage of
faeces may be confirmed by defaecation or the presence
of faeces on the floor. Jaundice may be observed
in non-pigmented areas of the skin such as the udder,
and neurological signs may be present in hepatic
encephalopathy.
Distension and changes in the silhouette of the abdomen
may be caused by distension of the rumen,
distension or displacement of the abomasum, distension
of the intestines, uterine enlargement, or fluid
accumulations within the peritoneum. Expansion of
the rumen can be caused by free gas bloat, frothy
bloat and excessive fibre fill. Displacement and distension
of the abomasum may be caused by right
side abomasal dilatation, displacement and torsion.
Distension of the intestines may be caused by caecal
dilatation and/or torsion and torsion of the greater
mesentery. Enlargement of the uterus occurs in
normal pregnancy and hydrops amnion/allantois.
Fluid accumulation in the peritoneal cavity may be
caused by ascites in congestive heart failure or urine
from a ruptured bladder.
Observations of the abdominal silhouette should
be made from a distance of several metres from
behind the animal to get an overall impression of its
shape. Viewing each side from an oblique angle can
be useful to highlight changes in the lateral contours.
The abdomen should be approximately symmetrical,
having a pear shape when viewed from behind
(Fig. 8.4). Regional changes can assist in identifying
the organ affected and the underlying condition.
For observational purposes the abdomen can be split
into four quadrants, left dorsal, left ventral, right
dorsal and right ventral. Abnormalities of contour
within each quadrant should be noted. In some conditions
the changes can be very subtle and further
confirmation of the diagnosis will be required.
The left costal arch is sometimes ‘sprung’ or pushed
outwards by a left displaced abomasum. Great care
is required to detect this minor change in abdominal
silhouette. Profound changes are more easily recognised.
Animals suffering from ruminal bloat have
a distended left dorsal quadrant (Fig. 8.5). Rightsided
abomasal dilatation causes a distension of
the right dorsal quadrant. Pneumoperitoneum
may cause bulging of the left and right dorsal quadrants
(Fig. 8.6) Cattle with vagal indigestion will
develop distension of the left dorsal quadrant and
the right ventral quadrant. This has been called a ‘ten
to four’ or a ‘papple’ profile. The papple shape refers
to the pear shaped contour on the right side and an
apple shaped contour on the left (Fig. 8.7). Hydrops
uteri and accummulations of fluid in the peritoneum
can cause gross distension of the right and left
ventral quadrants (Fig. 8.8). Bulging of the right ventral
quadrant, and to a lesser extent the left ventral
quadrant, occurs in late pregnancy in the normal
animal.
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