Ectoparasites Figure 2

Figure 2: Sarcoptes mites
Case history and photos of male rat (Sunny).

PATIENT: Sunny, a male rat born November 1, 1996, owned by RMCA member, Lisa Westplate.

Clinical Signs

First visit: February 2, 1997.
Sunny is a nice rat, very alert, eats and drinks normally; only his ears seem to be a bit irregular. There are many little, papillome-like irregularities on both ears. The rat is not bothered by any pruritus (itching). The rest of the body is perfect.

Second visit: February 25, 1997.
It is getting worse. Now the rat has pruritus (the ears are crusty). The rest of the body is still completely normal.

Third visit: February 28, 1997, University of Utrecht.
The rat is anesthetized and little parts of the ear are examined under the microscope. Surprise – there are a lot of sarcoptes mites. This is a rather unique phenomenon among rats.

Lisa's Sunny with Sarcopetes mites

Sunny Before Treatment
Photo by Lisa Westplate


Ivomec (ivermectin) Dosage: 0.2 mg/kg injected once a week for a period of three weeks (Editor’s note: ivermectin can also be given orally).


The prognosis is very good. Sunny completely recovered within a few weeks of the injections with very little permanent damage to the ears.

Lisa's Sunny recovered

Sunny After Treatment
Photo by Lisa Westplate

Editor’s Note (by Lisa): I was unable to find anything in any books about this condition and have never seen or heard about it from any other rat owners. Therefore, I think it is safe to say this is not something we have to worry about our rats getting, but it’s nice to know what it is and how to treat it if it ever does appear in our pet rat population.

*NOTE* This is a reprint of Lisa’s case study with permission of the RMCA.
Posthumous thanks go out to Lisa Westplate who gave of her time and love to so many ratties in need.*

Case study and photos by author Lisa Westplate courtesy of The Rat & Mouse Club of America


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