Ovine and Caprine Sinusitis Secondary to Dehorning – NAVLE Study Guide

Overview and Clinical Importance

Sinusitis secondary to dehorning is a relatively uncommon but clinically significant complication in small ruminants. This condition occurs when bacteria gain access to the frontal sinus through the exposed cornual diverticulum following horn removal. In sheep and goats, the frontal sinus communicates with the horn cavity via the cornual diverticulum, which becomes exposed when dehorning is performed after the horn has fused with the skull (typically after 1-2 weeks of age).

Small ruminants are at increased risk of sinusitis compared to cattle due to their relatively shallow frontal sinus and the proximity of the cornual process to the parietal bone. The condition can present acutely within days of dehorning or develop chronically months later, making early recognition and appropriate wound management essential for prevention.

Relevant Anatomy

Horn Structure in Small Ruminants

The horn of sheep and goats consists of a bony core (cornual process) that is an extension of the frontal bone, surrounded by a keratinized horn sheath produced by germinal epithelium at the base. The hollow space inside the bony horn is the cornual diverticulum, which is a direct extension of the frontal sinus.