Page 808 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Gastrointestinal system: 4.2 The lower gastrointestinal tr act 783

VetBooks.ir 4.111 4.112

Fig. 4.111 Survey abdominal radiograph in a foal Fig. 4.112 Barium enema in a foal with meconium
with meconium impaction. Note the radiodense impaction. The contrast dye stops at the level of the
meconium in the cranial abdomen (arrow). impaction.

4.113 4.114

Fig. 4.113 A pocket of peritoneal fluid (arrow) is Fig. 4.114 Ultrasonographic appearance of
evident ultrasonographically in a horse with acute haemoperitoneum in a horse with blunt abdominal
colic. trauma.

gas can also result in interference. However, using excessive coat. If image quality is not adequate, the
a combination of trans-abdominal and trans-rectal haircoat should be clipped. Ultrasonography can
approaches, a significant percentage of the abdomen be useful for identification of peritoneal effusion
can be examined. (Fig. 4.113), distended small intestine, thickened
In adult horses, 2.5–3.5-MHz probes are typi- intestinal walls, adhesions, masses, intussusceptions,
cally used, while the small size of foals allows for left dorsal displacement of the large colon, haemo-
the use of 5.0– 7.5-MHz probes. Examination of peritoneum (Fig. 4.114) and splenic abnormalities,
the abdomen should be approached in an organised among other lesions. It may also be used for the
manner to ensure that all relevant areas are exam- qualitative diagnosis of sand accumulation although
ined. Application of alcohol or methylated spirits to radiography is more accurate in quantifying the
the haircoat is usually adequate in horses without magnitude of sand accumulation.