[Yeasts in domestic animals: species identification and susceptibility to antifungals]

Yeasts frequently colonize various kinds of domestic animals, but may also cause serious diseases. The aim of this study was to identify yeast isolates collected from dogs, cows and pigs, and to determine their in vitro antifungal susceptibility. Fifty-six yeast isolates from dogs (n = 24), cows (n = 20), and pigs (n = 12) were investigated. Appearance of colonies grown on Sabouraud agar, micromorphology on rice agar, as well as assimilation and fermentation of various carbon and nitrogen sources were evaluated. Susceptibility to six antifungals (flucytosine, amphotericin B, miconazole, ketoconazole, itraconazole and fluconazole) was determined semiquantitatively using the commercially available Fungitest kit (Bio-Rad Laboratories). Ten yeast species were identified in dogs with relatively even distribution. On the other hand, cow and pig were clearly dominated by Candida krusei (from 7 species) and Candida rugosa (from 5 species), respectively. Further, most of yeast isolates exhibited good susceptibility to the antifungals tested particularly to amphotericin B, ketoconazole and itraconazole. Based on results, it can be concluded that significant differences in the species spectrum and distribution were documented between groups of yeasts from dogs, cows and pigs. This is probably due to different environmental conditions and the endogenous origin of the yeast isolates. Mostly good susceptibility to systemic antifungals should positively influence the therapy of diseases caused by yeasts in veterinary medicine.