Chilomastix bettencorti

Etiology: Chilomastix bettencorti are one celled, eukaryotic organisms.

Incidence: Incidence of infection is common.

Transmission: Fecal-oral transmission via ingestion of infective cysts.

Distribution: These protozoa are distributed in the cecum and colon.

Clinical signs: No clinical signs have been attributed directly to these organisms. These protozoa may proliferate in diarrheic states; however, their role as contributors to disease is poorly defined.


Antemortem: Difficult to diagnose antemortem. Wet mounts of fresh fecal material stained with a weak iodine solution may reveal typical lemon-shaped cysts that can be difficult to distinguish from plant material.

Postmortem: Wet mounts of intestinal contents may reveal pear-shaped trophozoites with a spiraling, jerky motion. The spiraling motion will aid in differentiation of Chilomastix trophozoites from trichomonads.

Diagnostic morphology:

Trophozoite: 10-15 µm long, pear- or lemon-shaped with 3 anterior flagella, a round anterior nucleus, a short, sharply pointed tail and a large cytostomal groove.

Cyst: 6-9 µm, lemon-shaped.