Chilomastix bettencorti

Etiology:  Chilomastix bettencorti is a flagellated protozoan.

Incidence:  The incidence of infection is common.

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

Distribution: Chilomastix bettencorti is 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 from fecal pellet samples. 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.