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Biotyping of Malassezia pachydermatis strains using the killer system

S D Coutinho1, C R Paula

  • 1Microbiology Department of the Biomedical Sciences Institute of the Universidade de São Paulo, Brazil. selene@uol.com.br.

Revista Iberoamericana De Micologia
|July 28, 2007
PubMed

Insights

This study identified Malassezia pachydermatis biotypes in dogs using killer yeasts. Biotypes 888, 212, and 111 were most common in ear and skin samples from dogs with otitis or dermatitis.

Area of Science:

  • Veterinary Mycology
  • Epidemiology

Background:

  • The killer phenomenon in yeasts serves as an epidemiological marker.
  • Candida albicans exhibits numerous biotypes based on killer activity.
  • Malassezia pachydermatis is a common cause of canine otitis and dermatitis.

Purpose of the Study:

  • To determine the biotypes of Malassezia pachydermatis strains isolated from dogs with otitis and dermatitis.
  • To observe the killer activity of Malassezia pachydermatis against a panel of killer yeasts.

Main Methods:

  • Thirty Malassezia pachydermatis strains (15 from otitis, 15 from dermatitis) were isolated from dogs.
  • Killer yeasts, grouped in triplets, were used to generate a 3-digit biotype code.
  • Growth inhibition of M. pachydermatis by killer yeasts was assessed.

Main Results:

  • The most frequent Malassezia pachydermatis biotypes identified were 888 (33.3%), 212 (26.7%), and 111 (16.7%).
  • Other identified biotypes included 312, 512, 242, 311, and 411.
  • Biotypes 888, 212, and 111 were prevalent in both ear canal and skin samples.

Conclusions:

  • Killer yeast-based biotyping is effective for characterizing Malassezia pachydermatis.
  • Specific biotypes of M. pachydermatis are frequently associated with canine skin and ear conditions.
  • Further research can utilize these biotypes for epidemiological studies of canine Malassezia infections.

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