The first case of Demodex gatoi in Austria, detected with fecal flotation

Feline demodicosis is a rare parasitic condition caused by three different species of mites ( Demodex cati , Demodex gatoi , and an unnamed species). D . gatoi inhabits the superficial skin layer (stratum corneum) and is easily transmitted between individual cats. A 2-year-old female spayed Cornish Rex was presented with alopecia and pruritus. The dermatological examination revealed bilateral alopecia and excoriations on trunk, limbs, and belly. The second cat in the household, a 3-year-old female spayed Thai, showed no clinical signs. Superficial and deep skin scrapings were performed and cellophane tapes applied, and living D . gatoi mites could be detected in both cats. Oral ivermectin (0.25 mg/kg every other day) was subscribed. Feces were collected from both cats and fecal flotation with sugar and zinc solutions performed. When compared to skin scrapings and cellophane tapes, D . gatoi was detected more frequently and in higher numbers in fecal samples. Our findings suggest that D . gatoi can be efficiently diagnosed with coproscopy, particularly in asymptomatic carrier animals. DNA was extracted from the flotation liquid, and a PCR protocol for the species verification was designed. A fragment targeting a 325-bp DNA fragment of the D . gatoi mitochondrial 16S rDNA gene was amplified with a 100 % similarity to the D . gatoi entry in GenBank® (GI 421920216). We report the first finding of D . gatoi in Austria and propose fecal flotation as a valuable tool for mite detection. Fecal flotation liquid is suitable for DNA extraction and PCR-based species verification of D . gatoi .