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

Abstract

Mastitis is one of the biggest problems of dairy cattle industries. In recent years, fungal agents have been frequently reportedamong the causative agents for mastitis. Among the fungal agents,Candidaspecies are the most common. This study s aims were theisolation, identification, and determination of antifungal susceptibility ofCandidaspecies causing mycotic mastitis in cattle. A total of260 mastitic milk samples were collected from different farms. Identification was conducted by rapid diagnostic tests and nested PCRmethod; 6 different antifungal agents were examined.Candidasp. was detected in 46 (17.7%) of the 260 mastitic milk samples. Based onAPI 20 C AUX and nested PCR test results, 6 different species ofCandidawere identified.C. tropicaliswas the predominant one (26.1%),followed byC. parasilosis(21.7%),C. kefyrandC. krusei(17.4% each),C. rugosa(13%), andC. glabrata(4.4%). A total of 46 strains wereconfirmed by PCR. According to antifungal test results, the isolates were found to be susceptible to ketoconazole (78.3%) and resistantto flucytosine (91.3%), amphotericin (82.6%), miconazole and nystatin (73.9%), and fluconazole (69.5%).