Application of multivariate analysis: toward improvement of rooster semen quality assessment

Sperm cryopreservation is an important tool for storage of genetic material of animal species. Therefore, the aim of this study was to assess the association between extender and cryoprotective agents (CPAs) used in the term of sperm quality parameters. In our study, the comparison of two extenders (Kobidil(+) (K+) and saline (S)) and their combinations with CPAs such as dimethyl sulfoxide (DMSO) or glycerol (GL) on the sperm motility and viability was analyzed. For detailed assessment of association between extenders with CPAs and sperm quality parameters of frozen/thawed semen, multivariate analysis was used. The obtained data showed that the both extenders with specific CPAs significantly affect the motility as well as the viability parameters. GL/K+ (p-value=0.0168) had effect on the progressive motility, whereas GL/S (p-value=0.0174) influenced the total motility and velocity curved line parameters. Moreover, DMSO/K+ (p-value=0.0346) had higher effect on the proportion of dead and apoptotic sperm compared to DMSO/S (p-value=0.036), which had higher impact on the proportion of acrosome damaged sperm. Future studies might benefit from these findings to establish the associations of these subpopulations with other rooster sperm quality parameters and thus improve the sperm quality. Association between the values can help us to better understand the effect of extenders and CPAs on the semen quality parameters.