How can vagal indigestion be differentiated from simple indigestion on physical examination?

• A. Vagal indigestion shows persistent progressive distension with poor eructation and abnormal rumen motility, whereas simple indigestion shows transient distension with improvement after feeding and normal appetite
• B. Vagal indigestion resolves quickly with feeding
• C. Simple indigestion always has severe weight loss
• D. Vagal indigestion has increased eructation

Answer: (A)

When trying to tell vagal indigestion from simple indigestion on a physical exam, focus on how the rumen handles gas and how the abdomen behaves over time. Vagal indigestion is a motor problem of the rumen due to vagal nerve dysfunction, so gas builds up and distension tends to be persistent and progressive. You’ll commonly find reduced or absent eructation and abnormal rumen motility—decreased or uncoordinated rumen contractions—with a markedly tympanitic, distended left abdomen. Appetite may be reduced and weight loss can occur because the problem is chronic and gas cannot be expelled properly.

In contrast, simple indigestion is more of a temporary functional upset. Distension tends to be transient and improves after feeding as the rumen processes the ingested material; eructation is generally normal and the rumen motility remains within normal limits, with appetite and body condition typically better preserved.

So the distinguishing feature is the persistent distension with poor eructation and abnormal rumen motility seen in vagal indigestion, versus transient distension that improves after feeding and normal appetite in simple indigestion.