|
Examination for Ectoparasites |  |
| Animals with dermatoses should be evaluated by examining for ectoparasites or evidence of their presence. For example, fleas may not be seen on a cat or dog, but small black flecks of excrement that produce a reddish stain when placed on a wet paper towel may be noted. Skin must sometimes be scraped to diagnose parasites. A scalpel blade is used for the deep scrapings (until blood oozes) needed to demonstrate parasites (eg,
Sarcoptes
,
Demodex
spp
) that live in burrows or hair follicles. The scraped material is placed in a drop of mineral oil on a slide, and the entire area under the coverglass is scanned under low-power magnification. A few drops of 10% potassium hydroxide solution may be added to clear debris and allow better visualization. |
