Equine Torsion Vs. Volvulus Colic

The colon in horses is extremely large when compared to that of other animals, and is loosely attached to surrounding structures. For these reasons, it is easily displaced, twisted and kinked. It is believed that a horse who rolls from side to side when experiencing colic--acute abdominal pain--may incur a volvulus, torsion or displacement of the colon. According to Dr. Byron Young, DVM, MS, the survival rate for horses with torsion or volvulus can be as high as 90 percent; unfortunately, delays in contacting the veterinarian or transporting the horse to a surgical facility decrease survival rates to 30 to 50 percent.

  1. Torsions

    • Torsion is a twisting of one section of the intestines around another section, resulting in insufficient blood flow and death to those sections of the intestine. It is called torsion when the twist is less than 360 degrees.

    Volvulus

    • When the intestine is twisted more than 360 degrees on its mesentery, it is called a volvulus. A volvulus results in a sudden shutting-off of the blood supply to the twisted portion of the bowel. The bowel itself may be twisted shut at one or both ends.

    Hypoperistalsis

    • A major indicator that torsion or volvulus is involved is hypoperistalsis--when there is little or no gut activity. Horses who have been given cold water after an intense workout, broken into the feed room and eaten too much, had their diets changed suddenly or are infested with a large amount of parasites can develop torsions and volvulus. Other symptoms include acute pain, elevated heart and respiration rates and inability to pass manure.

    Causes

    • Torsions and volvulus of the small intestine can be caused by adhesions, worm impactions and motility disorders associated with changes in diet, internal hernias and naval hernias. Lipomas--fatty tumor on a long stalk attached to the mesentery of the bowel--are also a common cause of volvulus in the small intestine.

    Treatment

    • Immediate surgery is necessary to untwist the intestine, unblock the flow of blood and save the horse. These types of colic can get very serious, very quickly. Therefore, it is vital to call your veterinarian every time your horse colics so he can determine whether or not it is torsion or volvulus colic. Treatment includes surgical unwinding of the twisted bowel. If the bowel is devitalized--the tissue of the intestine has died--that segment must be surgically removed.

    Prevention

    • Check all forage for molds before feeding to the horse.

      The horse owner can take certain steps to reduce the chance that the horse will suffer from colic. Keep the horse on a regular deforming schedule, do not overfeed the horse and feed at the same time every day, properly cool the horse after a training session, do not feed or water until cooled down, check all forage and grain for molds before feeding, and do not make sudden feed changes.