Characterization of the cutaneous mycobiota in Persian cats with severe dermatophytosis.

Persian cats are predisposed to chronic and severe dermatophytosis. Alterations to the cutaneous microbiota are one potential contributor to this predisposition. To characterise the cutaneous and environmental fungal microbiota of Persian cats with chronic, severe dermatophytosis, and to compare the fungal microbiota of cats with and without dermatophytosis. Thirty-six client-owned cats, including 26 Persian cats and 10 domestic long hair (DLH) cats. Skin and home environment swabs were collected from Persian cats with severe, chronic dermatophytosis as well as groups of healthy control cats (Persian and DLH). Sequencing of the internal transcribed spacer 1 (ITS1) region was performed in addition to ITS1 quantitative PCR and fungal culture. Next-generation sequencing (NGS) targeting the fungal ITS region detected Microsporum sp. DNA from all Persian cats diagnosed with dermatophytosis and from environmental samples of their homes. A significant difference in community structure was identified between cases and controls, largely resulting from the Microsporum spp. DNA in samples from affected cats. Persian cats with dermatophytosis do not exhibit decreased fungal diversity. NGS failed to identify dermatophyte DNA on two culture-positive asymptomatic Persian controls and identified Trichophyton rubrum DNA from a culture-negative asymptomatic Persian control. Aside from M. canis, our results indicate that an underlying fungal dysbiosis is not likely to play a role in development of dermatophytosis in Persian cats. Other explanations for predisposition to this disease, such as a primary immunodeficiency, ineffective grooming or unique features of Persian cat hair should be investigated.