TEMPERATURE AND RECTAL EXAM
Rectal Temperature: This is a critical parameter. Most colicky horses do not have an increased rectal temperature, thus this finding may help to rule out luminal or extra-luminal GI obstruction. Conversely, a colicky horse with a septic or infectious condition can have an elevated temperature usually from enteritis or peritonitis from a ruptured or necrotic bowel. Colic accompanied by an elevated temperature is a poor prognostic sign. A decreased temperature is usually a sign of circulatory collapse and is a grave sign. It is very important to obtain the rectal temperature before performing a rectal exam since air introduced into the rectum may falsely decrease the rectal temperature.
Rectal Exam: Feces, or the absence of feces, should be noted. If the horse offers resistance in the form of a peristaltic wave, one should follow the wave back until it dissipates by withdrawing the hand, or at least by not trying to extend the hand further into the rectum. Forcing one's way through the center of a peristaltic contraction is inviting rectal perforation in the horse. The pelvic flexure is a frequent site for impaction of ingesta because of its decreased lumen size and hairpin turn. In cases of obstruction, distended bowel is frequently palpable.
In a normal abdomen, the left side of the abdomen should reveal the distal left ventral colon, the pelvic flexure, the proximal left dorsal colon, the spleen, the left kidney and the left ovary. The ventral abdomen contains the bladder, inguinal rings, cervix and uterus. The right side of the abdomen contains the cecum and segments of the small colon. The small intestine is usually not palpable. In the cranial aspect of the dorsal abdomen, the root of the mesentery and the nephrosplenic ligament may be palpable.
RECTAL PALPATION DIAGRAMS