Identification of Candida strains with nested PCR in bovine mastitis and determination of antifungal susceptibilities

Mastitis is one of the biggest problems of dairy cattle industries. In recent years, fungal agents have been frequently reported among the causative agents for mastitis. Among the fungal agents, Candida species are the most common. This study's aims were the isolation, identification, and determination of antifungal susceptibility of Candida species causing mycotic mastitis in cattle. A total of 260 mastitic milk samples were collected from different farms. Identification was conducted by rapid diagnostic tests and nested PCR method; 6 different antifungal agents were examined. Candida sp. was detected in 46 (17.7%) of the 260 mastitic milk samples. Based on API 20 C AUX and nested PCR test results, 6 different species of Candida were identified. C. tropicalis was the predominant one (26.1%), followed by C. parasilosis (21.7%), C. kefyr and C. krusei (17.4% each), C. rugosa (13%), and C. glabrata (4.4%). A total of 46 strains were confirmed by PCR. According to antifungal test results, the isolates were found to be susceptible to ketoconazole (78.3%) and resistant to flucytosine (91.3%), amphotericin (82.6%), miconazole and nystatin (73.9%), and fluconazole (69.5%).