Yeasts in Feces of Pigeons (Columba livia) in the City of Moscow.

The yeast number and species diversity in feces of pigeons (Columba livia) were studied in various locations of the city of Moscow: parks, playgrounds and school grounds. The total number and species composition of yeasts in feces depended on the isolation temperature. The average yeast number at a cultivation temperature of 25 °C was 3.2 × 105 CFU/g, at 37 °C-2.5 × 106 CFU/g. At 37 °C, the number of yeasts was higher due to a more abundant growth of pathogenic and opportunistic yeast species. In total, 13 species of yeasts were isolated from feces: eight ascomycetes and five basidiomycetes. The study revealed high values of relative abundance and frequency of occurrence of pathogenic species Candida albicans and opportunistic yeasts, i.e. Diutina catenulata, Millerozyma farinosa, Pichia kudriavzevii, and Trichosporon asahii. Pigeon feces were found to present a constant source of "infection" of the urban environment with yeast species that are hazardous to human health, especially for immunosuppressive individuals.