FEBRUARY 1996 BACK ISSUE

Part of Horse Previews Magazine website. Posted on 2/1/96; 10:00:00 AM.

Combatting Colic: The Role of Endoctocemia

Colic describes a condition that encompasses a wide variety of conditions causing acute abdominal pain in the horse. It is highly prevalent and often fatal.

One of the leading reasons for colic's high fatality rate is the development of endotoxemia. Endotoxins are toxic components of the bacteria that reside in the intestines of all animals. If the intestinal wall is damaged, endotoxins escape into the bloodstream, causing massive stimulation of the horse's natural defense mechanisms and the release of mediators that decrease cardiovascular performance.

Morris Animal Foundation is sponsoring several studies investigating endotoxemia in relation to colic. Dr. Cynthia Trim of the University of Georgia is studying this relationship in the study entitled, "Changes in Blood Endotoxin Concentration in Horses Undergoing Surgery for Colic." She hypothesizes that endotoxins are in the bloodstream of 25 percent to 40 percent of horses with colic that are admitted to university clinics for surgery, Endotoxemic horses should receive specific treatments before surgery to counteract the effects of this over stumulation of the inflammatory system. These treatments are expensive and must be used early.

Dr. Trim suggests that manipulation of the intestine during colic surgery promotes the movement of harmful endotoxins. She and her colleagues are testing the blood of horses before and during surgery. Using these tests, the investigators aim to identify intestinal conditions and surgical procedures associated with the movement of harmful endotoxins and predict which horses need treatment to neutralize endotoxins. This Morris Animal Foundation sponsored study is being generously funded by trustee, Deborah L. Carter, in memory of "Phineas T." and "Mykonos."

A second Foundation-funded study at the University of Georgia is examining another aspect of the effects of endotoxemia. Dr. Michelle Henry Barton is principal investigator of the study entitled, "Efficacy of Monoclonal Antibody Against Recombinant Equine Tumor Necrosis Factor (TNF) in an In Vivo Model of Endotoxemia."

When endotoxins are released into the bloodstream of a horse, they cause cells in the blood to produce a substance called tumor necrosis factor (TNF) which usually causes shock and death. Dr. Barton and her colleagues have developed an antibody to TNF that inhibits the toxic effects of this protein (TNF) on cells in a cultured cell system. The purpose of this project is to test this antibody to determine if it will block the effects of TNF in horses.

Endotoxemia continues to be a deadly threat to horses with colic. Through the work and dedication of the investigators, these Morris Animal Foundation-funded studies may shed light on new ways to combat the often tragic results of this disorder.

Morris Animal Foundation Animal News Volume III 1995

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