title: Small Demodex populations colonize most parts of the skin of healthy dogs.
abstract: BACKGROUND
  It is unproven that all dogs harbour Demodex mites in their skin. In fact, several microscopic studies have failed to demonstrate mites in healthy dogs.
  
  
  OBJECTIVE
  Demodex canis is a normal inhabitant of the skin of most, if not all, dogs. This hypothesis was tested using a sensitive real-time PCR to detect Demodex DNA in the skin of dogs.
  
  
  METHODS
  One hundred dogs living in a humane society shelter, 20 privately owned and healthy dogs and eight dogs receiving immunosuppressive or antineoplastic therapy.
  
  
  METHODS
  Hair samples (250-300 hairs with their hair bulbs) were taken from five or 20 skin locations. A real-time PCR that amplifies a 166 bp sequence of the D. canis chitin synthase gene was used.
  
  
  RESULTS
  The percentage of positive dogs increased with the number of sampling points. When a large canine population was sampled at five cutaneous locations, 18% of dogs were positive for Demodex DNA. When 20 skin locations were sampled, all dogs tested positive for mite DNA. Our study indicates that Demodex colonization of the skin is present in all dogs, independent of age, sex, breed or coat. Nevertheless, the population of mites in a healthy dog appears to be small. Demodex DNA was amplified from all 20 cutaneous points investigated, without statistically significant differences.
  
  
  CONCLUSIONS
  Using a real-time PCR technique, Demodex mites, albeit in very low numbers, were found to be normal inhabitants of haired areas of the skin of healthy dogs.
authors: Department of Animal Medicine and Surgery             Servei Veterinari de Genètica Molecular, Veterinary School, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain.
authors: Iván
authors: I
authors: Ravera
authors: Laura
authors: L
authors: Altet
authors: Olga
authors: O
authors: Francino
authors: Armand
authors: A
authors: Sánchez
authors: Wendy
authors: W
authors: Roldán
authors: Sergio
authors: S
authors: Villanueva
authors: Mar
authors: M
authors: Bardagí
authors: Lluís
authors: L
authors: Ferrer
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000469:parasitology*; D004285:Dogs; D005260:Female; D016867:Immunocompromised Host; D008297:Male; D008924:Mite Infestations / Q000469:parasitology / Q000662:veterinary*; D008925:Mites / Q000145:classification*