Molecular detection of canine Leishmaniasis using conjunctival swab and buffy coat samples

Many molecular methods have been used for diagnose is of canine leishmaniasis. These methods mainly rely on tissue specimens provided by invasive approaches for molecular detection of leishmaniasis. The aim of this study was to evaluate two noninvasive sampling methods detection of Leishmaniasis using PCR method. For this purpose, a total of 60 dogs were selected and equally divided into three groups: pet dogs with cutaneous lesions (Group 1); pet dogs without cutaneous lesions (Group 2) and stray dogs (Group 3). After physical examination of dogs, eye swab and buffy coat samples were collected from each dog, also, tissue smears were prepared from the lesions of dogs in group 1. DNA of eye swab and buffy coat samples were extracted and used to detection of Leishmania species using PCR and semi-nested PCR tests. Blood smears were stained by Giemsa method for microscopic evaluation. Out of 60 dog, the DNA of four swab samples related to the dogs of Group3 and one swab and DNA of buffy coat sample in a dog in group 1 was infected with Leishmania infantum. Leishman bodies was only observed in tissue smear of one dog in group 1. Three positive samples were sequenced for confirmation of results. Based on the results of this study, Leishmania infantum infection is common among dogs in Mashhad area and it seems that ocular swab specimens can be used as a noninvasive method for molecular detection of leishmania infection in dogs.