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  • Clinical Parasitology Images: Gallery IV (Click on images for an enlarged view)

    Taenia spp eggs

    Egg (10x and 40x views) with an onchosphere and thick striated shell). Taeniid eggs don't float well and although found in fecals they are usually retained in the gravid proglottid that passes in the feces. Taeniids are transmitted by ingestion of infected mammals.

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    Dipylidium caninum egg packet with many individual eggs

    Diagnostic for the double-pored tapeworm in dogs and cats. This tapeworm is transmitted by fleas.

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    Anoplocephalan tapeworm egg

    Oncosphere with a pyriform apparatus. Parasites of horses and ruminants. Transmitted by grass, psoscid or soil mites of various types.

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    Mesocestoides spp egg

    Onchosphere with a thin shell or embryophore. Shell is thinner than other tapeworms. Parasites transmitted as tetrathyridia found in peritoneal cavities of various hosts (snakes, birds, frogs, etc). Occassionally the larval stages are found in the peritoneal cavity of dogs.

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    Toxocara canis egg

    The primary distinquishing feature of this egg is the deep cup-like pits covering the surface of the shell. High dry examination of the shell surface is necessary for positive identification. Larval stages of ascarids with this type shell all migrate in the tissues. Some are important causes of visceral larval migrans (VLM), an important disease in humans and other animal species.

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    Toxascaris leonina eggs

    This parasite does not migrate in the tissues and is not a cause of VLM. The eggs are smooth on the outside with a thatched appearance on the inside. Found in both cats and dogs.

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    Toxocara and Toxascaris eggs

    Eggs shown together to demonstrate the morphologic differences.

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    Ascaris suum egg

    This pig ascarid is an occassional cause of visceral larval migrans in humans. In pigs, the migrating larvae produce milky lesions beneath the liver capsule and respiratiory sings may occur in young pigs. The egg is oval with a rolling surface.

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    Parascaris equorum egg

    This is the horse ascarid. Eggs are found in two forms in the same fecal samples. Some eggs (as shown) have a dense covering that obscures the details of the content of the egg. Others do not have the outer covering and are round and Toxascaris-like.

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    Trichuris sp. egg

    Whipworm eggs are bilaterally symetrical, have prominent plugs, are dare in phenolic in color and have no aberations in the shell wall. The eggs are slightly larger than Ancylostoma eggs. Whipworms are seldom found in cats, but are common in most other animal species.

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