Evaluation of Spermatological Parameters of Frozen Bull Semen with Conventional and CASA (Computer-Aided Sperm Analysis) Method

The aim of this study was to compare the assessments made by the CASA system and subjective method (by using phase-contrast microscope) for spermatological examinations of imported and locally produced semen. Frozen semen (imported and local production) belonging to 20 different bulls was examined by phase contrast light microscope method (conventional method) and method supported by computer (CASA method) for evaluating the principle semen characteristics. For imported semen, considering the average values of samples examined by the two methods, significant differences (P<0.05) were observed in the values of motility and concentration as well as the rates of abnormal and dead spermatozoa. For domestic semen, significant differences (P<0.05) were observed for the concentration of samples by the conventional evaluations and for the assessment of motility and concentration by the CASA method. It was observed that there were significantly (P<0.05) higher data only for the concentration assessed by both methods, while no such differences between the values of motility as well as the rates of abnormal and dead spermatozoa were found when considering the general average rates. By using the two methods, findings from the examination of pre-determined parameters were compared and their reliabilities were displayed herein.