ABSTRACT
In foals, colic signs can be mild to severe.1 Many different disorders can cause pronounced signs of abdominal pain in foals, and often these cannot be differentiated without a thorough evaluation, including passing a nasogastric tube, radiography, ultrasonography, CBC, chemistry profile, and abdominal fluid analysis (see Chapters 15 and 22). In many foals, gastric ulcers occur secondary to enteritis, and these foals often present with fever and an increased peripheral WBC count. Whereas the enteritis may be the cause of fever and lethargy, the ulcers are often the cause of the presenting signs of abdominal discomfort. Nasogastric intubation may recover dark brown fluid, which is indicative of bleeding ulcers. Unfortunately, signs of colic that are caused by ulcers are often only apparent when ulcers are severe (Figure 34-1) or severe complications have occurred, such as pyloric/duodenal stenosis (Figures 34-2 and 34-3), esophagitis (Figure 34-4), megaesophagus, or gastric perforation.
In adult horses, gastric ulcers can both cause colic and result from other disorders that cause colic.2 In horses in which ulcers are a primary cause of colic, discomfort is usually mild to moderate, and episodes of colic are often frequent and recurrent. In rare cases, ulcers may cause such severe pain that exploratory surgery is performed. The author sometimes has associated ulcers with recurrent episodes of gaseous distention of the large intestine. This may be a visceral sympathetic response to gastric pain.
