A retrospective study was conducted on 350 dogs suspected of having scabies, and 1,345 dogs with various dermatoses affecting the pinnae wherein the pinnal-pedal reflex was negative. Skin scrapings were positive in 29% of the dogs that responded to miticidal therapy. The pinnal-pedal reflex was positive in 78.4% of the dogs with confirmed (mites found in skin scrapings) and presumed (skin scrapings negative, but dog cured with miticidal therapy) scabies, and all of these had lesions on the pinnal margins. In contrast, only 1 to 12% of the dogs with other pinnal diseases had a positive pinnal-pedal reflex. Eighty-three percent of the dogs suspected of having scabies, but with negative skin scrapings, were cured with miticidal therapy. Dogs suspected of having scabies but not responding to miticidal therapy most commonly had atopic dermatitis or food allergy. Scabies accounted for 3.8% of the canine dermatology cases, and no age, breed, or sex predilections were observed.

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