Endoparasites Figure 1

Figure 1: Endoparsite slides and description
courtesy of IDEXX RADIL

Protozoa (flagellates)

Spironucleus muris Slide 1:  shows photo of the cyst and trophozoite form of Spironucleus muris. Note the teardrop shape of the trophozoite and its flagella (there are six anterior and two posterior).

Spironucleus muris Slide 2:  shows photo of electron micrograph of Spironucleus muris. Again note its shape and flagella

Giardia muris Slide 3:  shows photo of differential interference contrast (DIC) photo of a Giardia muris trophozoite. Note the two anterior nuclei (“eyespots”) which give the organism a “monkey face” appearance.

Tritrichomonas muris Slide 4:  is a DIC photo of the trophozoite of Tritrichomonas muris. Note its lemon shape (Tritrichomonas sp. also have a characteristic undulating membrane and three flagella; these features are not evident on this slide but should be apparent on wet mounts). NOTE: Tritrichomonas sp. do not form true cysts.


Syphacia muris Slide 1:  is a photo of a female Syphacia muris, the rat pinworm. Note the location of the vulva (slightly caudal to that of Syphacia obvelata). The vulva os Syphacia muris is located in the anterior fourth of the body.

Syphacia muris Slide 2:  is a photo of a tape test of a rat infected with Syphacia muris. Note the shorter slightly banana-shaped ova as compared to ova of Syphacia obvelata.

Aspiculuris tetraptera Slide 3:  is a photo of Aspiculuris tetraptera, another rodent pinworm. Note the characteristic oval esophageal bulb and prominent cervical alae.

Aspiculuris tetraptera Slide 4:  is a photo of the tail of a male Aspiculuris tetraptera.
Note the blunted point.


Trichosomoides crassicauda Slide 5:  is a photo of a direct smear of urine from a rat infected with Trichosomoides crassicauda, the rat bladder worm.

Trichosomoides crassicauda Slide 6:  is a photo of a histologic section of a bladder from a rat infected with Trichosomoides crassicauda. Note the sections of worms within the bladder mucosa.


Slide 7:  is a differential interference contrast (DIC) photo of the head of an adult Hymenolepis nana. Note the four prominent suckers and “armed” rostellum.

Hymenolepis nana Slide 8:  is a photo of an egg of Hymenolepis nana. Note the three pairs of hooks.

Cestodes (intermediate host)

Taenia Slide 9:  is a photo of a mouse infected with Cysticercus fasciolaris, the intermediate form of the cat tapeworm Taenia taeniaformis. Note multiple cystic structures attached to the liver.

Slides and descriptions courtesy of:
DISEASES OF RESEARCH ANIMALS-DORA University of Missouri (Comparative Medicine Program and IDEXX-BioAnalytics)


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