Etiology: Trichomonas species (muris, minuta, wenyoni) are one celled, eukaryotic organisms.
Incidence: Incidence of trichomonad infection is common.
Transmission: Transmission is fecal-oral via ingestion of infective cysts.
Distribution: Giardia muris is found in the anterior small intestine.
Clinical Signs: Clinical signs are not usually observed. These protozoa may proliferate in diarrheic states, however their role as contributors to disease is poorly defined.
Diagnosis:
Antemortem: Fecal PCR can be used. Wet mounts of fresh fecal material or use of sucrose gradient may reveal cyst forms (this method of diagnosis is difficult).
Postmortem: Wet mounts of cecal contents reveal slow moving, flagellated protozoa with an undulating membrane. Trichomonads move with a jerky, wobbly, undirected motion.
Diagnostic morphology: Pear- to lemon-shaped trophozoites with an undulating membrane and 3 (tri-) to 4 (tetra-) anterior flagella. There is NO true cyst form.
T. muris 16-26 x 10-14 µm
T. minuta 4-9 x 2-5 µm
T. wenyoni 6-16 x 3-6 µm
Histopathologic examination may also be used to diagnose trichomonad infection.
Etiology: Chilomastix bettencorti is a one celled, eukaryotic organism.
Incidence: Incidence of infection with Chilomastix bettencorti is common.
Transmission: Fecal-oral transmission via ingestion of infective cysts.
Distribution: Chilomastix bettencorti is found in the cecum and colon.
Clinical signs: Clinical signs are not usually observed. These protozoa may proliferate in diarrheic states, however their role as contributors to disease is poorly defined.
Diagnosis:
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.
Etiology: Spironucleus muris is a flagellated protozoan.
Incidence: The incidence of infection is low in conventional gerbil colonies.
Transmission: Ingestion of infective cysts passed in fecal material is the primary mode of transmission.
Distribution: Found primarily in the crypts of the duodenum and pyloric glands. In young animals, luminal protozoa are more numerous.
Clinical Signs: Clinical signs are not usually observed.
Diagnosis: Direct smears of small intestinal contents reveal fast darting protozoa. Fecal PCR may also be used.
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Diagnostic Morphology: Trophozoite: 7- 9 x 2- 3 µm, piriform (teardrop)-shaped or carrot-shaped, with 6 anterior flagella, 2 posterior flagella, 2 anterior nuclei and 2 separate axostyles.
Etiology: Giardia muris is a one-celled eukarytic organism.
Incidence: Infection with Giardia muris is rare.
Transmission: Fecal-oral transmission via ingestion of infective cysts.
Distribution: Giardia muris is found in the anterior small intestine.
Clinical signs: Clinical signs are not usually observed. These protozoa may proliferate in diarrheic states, however their role as contributors to disease is poorly defined.
Diagnosis:
Antemortem: Fecal PCR can be used. Wet mounts of fresh fecal material or use of sucrose gradient may reveal cyst forms (difficult).
Postmortem: Wet mounts of intestinal contents may reveal slow-moving flagellated protozoa with a “falling leaf” rolling motility. Histopathologic examination may also be used to diagnose Giardia species infection.
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Diagnostic morphology: Broad, piriform trophozoite with 2 anterior nuclei that when stained with weak iodine solution gives the appearance of a “monkey face.” There are eight caudally directed flagella.