Is Malassezia nana the main species in horses' ear canal microbiome?

The objective of this study was to characterize genotypically Malassezia spp. isolated from the external ear canal of healthy horses. Fifty-five horses, 39 (70.9%) males and 16 (29.1%) females, from different breeds and adults were studied. External ear canals were cleaned and a sterile cotton swab...

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Bibliographic Details
Authors: Aldrovandi, Ana Lucia, Osugui, Lika [UNIFESP], Acqua Coutinho, Selene Dall'
Format: article
Status:Published version
Publication Date:2016
Country:Brasil
Institution:Universidade Federal de São Paulo (UNIFESP)
Repository:Repositório Institucional da UNIFESP
Language:English
OAI Identifier:oai:repositorio.unifesp.br:11600/57648
Online Access:http://dx.doi.org/10.1016/j.bjm.2016.04.017
https://repositorio.unifesp.br/handle/11600/57648
Access Level:Open access
Keyword:Malassezia nana
Malassezia slooffiae
Microbiome
Horses
Ear canal
Description
Summary:The objective of this study was to characterize genotypically Malassezia spp. isolated from the external ear canal of healthy horses. Fifty-five horses, 39 (70.9%) males and 16 (29.1%) females, from different breeds and adults were studied. External ear canals were cleaned and a sterile cotton swab was introduced to collect cerumen. A total of 110 samples were cultured into Dixon medium and were incubated at 32 degrees C for up to 15 days. Macro- and micromorphology and phenotypic identification were performed. DNA was extracted, strains were submitted to polymerase chain reaction technique, and the products obtained were submitted to Restriction Fragment Length Polymorphism using the restriction enzymes BstCI and HhaI. Strains were sent off to genetic sequencing of the regions 26S rDNA D1/D2 and ITS1-5.85-ITS2 rDNA. Malassezia spp. were isolated from 33/55 (60%) animals and 52/110 (47%) ear canals. No growth on Sabouraud dextrose agar was observed, confirming the lipid dependence of all strains. Polymerase chain reaction-Restriction fragment length polymorphism permitted the molecular identification of Malassezia nana-42/52 (81%) and Malassezia slooffiae- 10/52 (19%). Sequencing confirmed RFLP identification. It was surprising that M. nana represented over 80% of the strains and no Malassezia equina was isolated in this study, differing from what was expected. (C) 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license