Isolation and characterization of Cyniclomyces guttulatus (Robin) Van Der Walt and Scott, 1971 in dogs in Brazil.

Vegetative cells of an ascomycetous yeast, morphologically consistent with published descriptions of Cyniclomyces guttulatus, were observed in large numbers in the feces and stomach washes of three dogs with a recurrent medical history characterized by vomiting and diarrhea. Nucleotide sequence analysis of an approximately 600 base pair fragment of the variable D1/D2 domain of large subunit (26S) ribosomal DNA of a pure culture, isolated from a Siberian Husky, revealed 98-99 % homology to sequences deposited in the GenBank as C. guttulatus. These data represent the first observation of C. guttulatus in association with canine gastrointestinal illness in the southern hemisphere and add weight to the hypothesis that this yeast may act as an opportunistic pathogen of dogs. An extended examination of wet mounts and smears prepared from feces collected from 63 dogs with no clinical symptoms of gastrointestinal illness, identified C. gluttulatus in 14 (22.2 %) of the animals, albeit at lower numbers than in diseased dogs, indicating that this yeast species is widely distributed as a component of the normal microflora of the canine gastrointestinal tract.