Acute gastric dilation is a sudden painful distention of the stomach due to a buildup of fluid or gas. The most commmon cause is grain engorgement. The grain forms a packed mass in the stomach that ferments and draws fluid into itself. Allowing a horse to drink cold water after a heavy workout is another cause of gastric dilation.
A secondary type of gastric distention occurs when there is an obstruction in the small intestine or colon. The fecal contents of the bowel back up into the stomach. The stomach progressively enlarges because the horse cannot vomit to relieve the pressure. The pain of acute gastric dilation is severe and violent. It is accompanied by rolling, sweating, kicking at the abdomen, and turning the head as if to bite at the abdomen. Heart and respiratory rates are increased. The horse may exhibit shock with cold extremities.
Chronic gastric dilationis a milder condition found in horses who crib and swallow large amounts of air. It also occurs in horses who suffer from gastritis, and those who eat and drink immediately after strenuous exercise. If the horse shows signs of abdominal distress, notify your veterinarian at once. Gastric rupture is a fatal complication of acute gastric dilation and is likely to occur if the distended stomach is not decompressed. Irrigating and flushing the stomach will relieve the problem caused by overeating or over-drinking. Dioctryl sodium sulfosuccinate (DSS) helps to soften a grain impaction. Most horses with gastric dilation are dehydrated and have electrolyte and acid-base imbalances. These are usually corrected by appropriate intavenous therapy. Acute laminitis (founder) may accompany or follow an episode of acute gastric dilation.