Isolation and Molecular Characterization of Bovine Trichophyton verrucosum Strains Based on Sequence Analysis of Internal Transcribed Spacer Region (ITS1) and Microsatellite Loci

The aim of this study was to isolate Trichophyton verrucosum from cattle and investigate the genetic diversity of the isolated strains by sequencing ITS1 region and by fragment length analysis of microsatellite loci. In this study, 84 hair and skin scraping samples from cattle with dermatophytosis were investigated by direct microscopy and culture methods. Furthermore, DNA was isolated from the colonies and sequence of ITS1 region was determined by direct sequencing. In addition, primers were designed for amplification of 11 loci showing simple tandem repeats (CHFD, SRT, HP1, HP2, HP3, HP4 TVMS1, TVMS2, TVMS3, TVMS4 and TVMS5) and PCR products of each locus were examined by fragment length analysis. Out of 84 samples 25 (29.7%) T. verrucosum strains were isolated. Sequence analysis of ITS1 region revealed that all strains have the same sequence. The observed fragment lengths of the microsatellite loci CHFD, SRT, HP1, HP2, HP3, HP4 TVMS1, TVMS2, TVMS3, TVMS4 and TVMS5 were 136 bp, 170 bp 178 bp, 423 bp, 356 bp, 225 bp, 232 bp, 201 bp, 270bp, 173 bp, respectively. None of the microsatellite loci examined showed fragment length variation among the samples included into the study. The results suggested that dermatophyte species could be distinguished based on the sequence of ITS1 region, while absence of sequence variation at ITS1 region did not allow distinguishing between T. verrucosum strains. On the other hand, no fragment length variation of the microsatellite loci among the T. verrucosum strains examined was observed. (C) 2018 PVJ. All rights reserved