Effect of different washing solutions used during cryopreservation of boar semen on post-thawing sperm viability. Frozen-thawed spermatozoa were stained with Sybr-14/PI and examined under green and red fluorescence. Stained spermatozoa were classified as live (Sybr-14+) or dead (PI+). Values are expressed as the mean ± SE. Letters a and b represent significant differences between groups (p < 0.05). Error bars show the standard error of the mean.