Major causes of noninfectious GI disease include the following:
dietary issues (eg, feed overload, intolerance, allergy)
dietary indiscretion, including foreign body ingestion
GI obstruction
mucosal injury (eg, gastric ulcers,chronic enteropathy, neoplasia)
intestinal dysbiosis
enzyme deficiencies
congenital defects
Clinical signs of noninfectious GI disease, including vomiting and diarrhea, may develop secondary to systemic or metabolic diseases such as kidney disease, liver disease, and Addison disease (hypoadrenocorticism). The causes are uncertain in several diseases, including abomasal ulcers in cattle, gastric ulcers in pigs, gastric ulcers in foals, gastric torsion in dogs, and acute intestinal obstruction and abomasal displacement in cattle.
With noninfectious GI diseases, usually only a single animal is affected at one time; exceptions are diseases associated with excessive feed intake or poisons, in which case herd outbreaks are common.