What is vagal indigestion and what does the disturbance in motility involve?

• A. A congenital gastric outlet obstruction with obstruction; no relation to vagus
• B. A functional forestomach disorder due to vagus nerve disruption causing abnormal motility and outflow; progressive distension
• C. A disease of rumen bacteria causing gas production only
• D. A mechanical obstruction of the esophagus

Answer: (B)

Vagal indigestion is a functional disturbance of forestomach motility caused by disruption of the vagus nerve pathways that coordinate contractions and outflow from the rumen, reticulum, and omasum. Because the neural signals guiding normal motility are impaired, the contents don’t move properly toward the downstream stomachs, and eructation and forward flow are reduced. Over time this leads to progressive distension of the forestomachs as gas and ingesta accumulate.

This option is the best because it accurately describes both the neural (vagus-related) cause and the resulting abnormal motility with impaired outflow, plus the consequence of progressive distension. It isn’t a fixed mechanical blockage or a bacterial gas-production issue alone, and it isn’t a simple esophageal obstruction or a congenital lesion, which is why the other descriptions don’t fit the condition.