The Assessment of Cryopreservation on the Quality of Endangered Oravka Rooster Spermatozoa Using Casa and Cytometry.

BACKGROUND: Preservation of genetic resources in gene bank is necessary for conservation of endangered poultry species. OBJECTIVE: This study is to characterize Oravka rooster semen quality. MATERIALS AND METHODS: Heterospermic pool was diluted (1:1 by volume) in a freeze medium composed of a commercial diluent (Kobidil+, K), 8% dimethyl sulphoxide (DMSO) or 8% ethylene glycol (EG) or 8% glycerol (GL), and then frozen in liquid nitrogen vapour. RESULTS: Spermatozoa in the GL/K+ had significantly higher number of motile and progressively moving spermatozoa (p < 0.05) than in DMSO/K+ and EG/K+ groups. The percentage of apoptotic and necrotic spermatozoa were significantly higher in the DMSO/K+ and EG/K+ groups compared with the GL/K+ group. Based on the total motility, progressive movement parameters and viability, our study showed that 8% GL diluted in Kobidil+ provided the highest cryoprotective effect on the Oravka rooster spermatozoa.