April 2020

Which came first the parasite or the egg?

A fecal sample from a 6-month-old, spayed female, Siamese cat was submitted for a gastrointestinal parasite evaluation.  The cat did not show any symptoms at submittal. For fecal analysis, a centrifugal fecal flotation with Sheather’s sugar solution (specific gravity, 1.26) was performed, and a low number of these eggs were observed 

Image 1: 100X magnification

Image 2: 400X magnification 

What's your diagnosis?

Demodex spp. eggs.

The fecal sample also showed Demodex spp. adults (Image 3)
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Image 3: 200X magnification

Demodex spp. are small wormlike mites with short legs, they live in the hair follicles and sebaceous glands of mammals.  Several species of Demodex often parasitize the same animal host, but each species tends to be restricted to a particular location. In cats, dermatitis associated with Demodex cati is rarely noticed and is usually localized on the head and in the ear canals.  Demodex gatoi, is a much shorter and is more superficially dwelling than D. cati. Cases of feline demodicosis are believed to be associated with underlying immunosuppressive diseases.