Candidiasis in Birds (Galliformes, Anseriformes, Psittaciformes, Passeriformes, and Columbiformes): A Focus on Antifungal Susceptibility Pattern of Candida albicans and Non-albicans Isolates in Avian Clinical Specimens

Candidiasis is a fungal infection caused by Candida species which has been reported in most domestic and wild birds and mammals. In this study, 196 samples from different species of birds with suspected symptoms of candidiasis were examined. Pharyngeal swabs, cloacal swabs, and fecal samples were taken from the birds. The samples were cultured in sabouraud dextrose agar (SDA) containing cycloheximide and chloramphenicol and incubated at 42°C. Suspected isolates of Candida were identified using PCR. To detect the candida genus, a primer set to target the candida rDNA (ITS1-ITS4) was selected. To detect Candida albicans (C albicans), a primer set to target cytochrome P-450 lanosterol-a-demethylase (P450-LIAl) gene (DH-1558) was selected. In direct microscopic observation and culture, 28.57% of the birds were suspected of candidiasis. In the molecular study, candidiasis was confirmed in 25% of the birds, and candidiasis caused by C albicans was confirmed in 14.28% of the birds. All isolates were subjected to antibiotic susceptibility by the disk diffusion method with glucose-enriched Mueller-Hinton Agar. 78.5% of the isolates were sensitive to nystatin and amphotericin B. None of the isolates were sensitive to itraconazole and more than 50% of the isolates were resistant to fluconazole, ketoconazole, and itraconazole. According to the results, it is suggested to use nystatin and amphotericin B in the treatment of avian candidiasis in the Ahvaz region. To the authors' knowledge, this is the first report of the molecular detection and antifungal susceptibility pattern of C albicans and non- albicans from Galliformes, Anseriformes, Psittaciformes, and Passeriformes in Iran.