책임운영기관 농촌진흥청 국립축산과학원 (로고)

Trichophyton verrucosum causes a highly contagious disease in bovine and can be occasionally transmitted to humans. Azoles widely used as antifungal drugs in bovine, act by targeting the ergosterol biosynthesis pathway. However, cases of failure and relapse of dermatophyte infection due to gene mutations in the drug target site have been reported. Subtilisin (SUB) genes are involved in pathogenesis. However, information is lacking regarding T. verrucosum variants. This study aimed to classify T. verrucosum variants isolated from animals with clinical symptoms and cattle environments in the Republic of Korea based on their antifungal susceptibility and the presence or absence of ergosterol biosynthesis (ERG) and SUB genes. Of 139 clinical samples and 39 environmental samples, 86 and 21 were found to be infected, respectively. The positive ratio of calves aged 1–6 months was 73.1%, which was significantly higher than that of calves aged >6 months (55.2%). Twenty-seven T. verrucosum strains were identified as T. album (n = 9), T. ochraceum (n = 6), and T. discoides (n = 12). Antifungal susceptibility testing showed that enilconazole had the lowest geometric mean antifungal activity, of 1.08, 1, and 0.94 μg/ml against T. album, T. ochraceum, and T. discoides, respectively. In conclusion, our study suggested conducting sample cultures and antifungal susceptibility tests on isolates before administering antifungal drugs. Moreover, the expression profile of the ERG gene appears to have a potential link to drug susceptibility. This information may help prevent and manage dermatophytosis in cattle