Sperm motility and viability in boar sperm diluted in long-term extender containing different type of kofola

The objective of this study was to evaluate the sperm motility and viability of boar sperm diluted in long-term extender containing different types of kofola. Eight sperm rich fractions from 4 fertile boars from one AI centre with motility ≥80% and the number of morphologically abnormal spermatozoa ≤25% were used in this study. Tested types of kofola: mix of spices – KS (cinnamon extract 100mg/l and clove extract 100mg/l) and honey – KH (honey extract 100mg/l) were added to boar semen extender Androstar plus (AS+). Semen was diluted in AS+ as a control (K) and AS+ with addition of different types of kofola in the dilution ratio 1+2. Samples were stored at 17°C and evaluated after 0h, 48h, 92h and 168h storage time for sperm motility and sperm viability. SCA system was used for determined sperm motility (total, progressive, non-progressive and immotile) and kinetic characteristics - straight line velocity (VSL, μm/s), average path velocity (VAP, μm/s), curvilinear velocity (VCL, μm/s), straightness (STR, %), linearity (LIN, %), wobble (WOB, %). Statistically significant differences in total mean values of total sperm motility, progressive and immotile sperm (P<0.05) were recorded between K (94.47, 73.91, 5.53%) vs. KH (85.58, 59.85, 14.43%) and KS (87.10, 60.96, 12.91%). The sperm survival was significantly affected by storage time (P<0.05). Kinetic indicator of speed VCL and LIN reported significant differences between K (57.73 µm/s, 36.16%) vs. KH (49.10 µm/s, 39.52%) P<0.05. No differences were found in percentage of sperm viability (P>0.05) between K (77.75%) vs. KH (77.88%) and KS (79.81%). In conclusion, application of tested types of kofola as a potential component to the boar extender unfortunately did not have a positive effect on boar sperm motility, but the sperm viability was not adversely affected.