Figure 7-106.

Torsion, Large Colon, Horse.

A, Rotation of the colon on its long axis has resulted in severe colic with strangulation (arrow). Note the red to blue discoloration of the colon distal to the torsion caused by obstruction of venous blood flow. B, Note the sharp line of demarcation (point where the torsion occurred) between viable colon (to the right) and nonviable colon (to the left) caused by obstruction of venous blood flow. In this case, the torsion was not found at the time of necropsy; however, a torsion will commonly untwist itself (reduce itself) during transport of the cadaver to the postmortem room.

(A courtesy Dr. H. Gelberg, College of Veterinary Medicine, Oregon State University. B courtesy Dr. M.D. McCracken, College of Veterinary Medicine, University of Tennessee.)