Stomatitis in Large Animals

Stomatitis is a clinical sign of many diseases in large animals, including infectious, traumatic, and toxic etiologies.

Differential diagnoses for stomatitis include actinobacillosis, foot-and-mouth disease, malignant catarrhal fever, and bovine viral diarrhea. Epidemic diseases such as bluetongue in ruminants, swine vesicular disease, and vesicular stomatitis in horses must be differentiated from other forms of acute noninfectious or infectious stomatitis.

Oral trauma or contact with chemical irritants (eg, caustic agents that are used to "blister" horses and then are ingested when the horse licks its legs) can result in transient stomatitis.

Traumatic injury from ingesting the awns of barley, foxtail, porcupine grass, or spear grass, as well as from feeding on plants infested with hairy caterpillars, also can result in stomatitis in horses and cattle.

Clinical signs commonly associated with acute active stomatitis include ptyalism, dysphagia, and resistance to oral examination.

Oral examination is facilitated by sedation, after which the mouth can be examined carefully with the aid of a mouth speculum and a light source. Ulcers should be visually and digitally evaluated to determine whether embedded foreign material (eg, grass awns) is present.

If the ingestion of foreign material is the cause of stomatitis, changing the quality and quantity of the hay or removing the animal from a pasture with grass awns can bring about recovery.