Observing a 'zippy' motility in fresh feces is used to help diagnose the presence of which parasite?

Observing a 'zippy' motility in fresh feces is used to help diagnose the presence of which parasite?

• A. Toxoplasma
• B. Mycoplasma
• C. Tritrichomonas
• D. Ehrlichia canis

Answer: (C)

A rapidly energetic, or "zippy," movement seen in a fresh fecal smear points to a flagellated protozoan that lives in the cat’s intestinal tract—Tritrichomonas foetus. Trophozoites of this organism swim with vigorous, jerky motility, which is best observed in a direct saline preparation of freshly collected feces. Because these trophozoites are fragile, motility can disappear quickly if the sample sits or is preserved, so prompt examination is important. Other organisms listed don’t produce this characteristic movement in a fresh stool: Toxoplasma gondii is identified by serology or detection of oocysts/tissue stages rather than quick fecal motility; Mycoplasma and Ehrlichia canis are bacteria diagnosed by blood tests or PCR, not by observing motility in feces.

A rapidly energetic, or "zippy," movement seen in a fresh fecal smear points to a flagellated protozoan that lives in the cat’s intestinal tract—Tritrichomonas foetus. Trophozoites of this organism swim with vigorous, jerky motility, which is best observed in a direct saline preparation of freshly collected feces. Because these trophozoites are fragile, motility can disappear quickly if the sample sits or is preserved, so prompt examination is important. Other organisms listed don’t produce this characteristic movement in a fresh stool: Toxoplasma gondii is identified by serology or detection of oocysts/tissue stages rather than quick fecal motility; Mycoplasma and Ehrlichia canis are bacteria diagnosed by blood tests or PCR, not by observing motility in feces.