A 5-year-old infertile Hutsul mare was subjected to cytogenetic analysis. Fluorescence in situ hybridisation (FISH) using the equine Xp and Xq chromosome painting probes was carried out on chromosome preparations obtained after blood lymphocyte culture. These probes were generated by chromosome microdissection and a large number of spreads was analysed (525). The karyotype formula of the analysed mare was 64,XX/65,XX+Xp with the ratio of the two lines being 99.4 and 0.6, respectively. The goal of the study was to apply chromosome microdissection and the FISH technique for cytogenetic diagnostics.