Effect of hyaluronan supplementation on boar sperm motility and membrane lipid architecture status after cryopreservation

We investigated the effect of supplementing extended boar semen with different amounts of hyaluronan (HA) prior to freezing on post-thaw sperm characteristics. Using a split sample design, the effect of HA at a final concentration of 500 or 1000 mug/ml semen on post-thaw motility parameters, and membrane lipid architecture status assessed by merocyanine-540/YOPRO-1 and flow cytometry were evaluated. HA-supplementation improved motility parameters (P < 0.05 to P < 0.001) and decreased the percentage of hyperactivated spermatozoa (P < 0.05). HA-supplemented samples had more spermatozoa showing high lipid membrane stability as assessed with merocyanine-540. In conclusion, HA appeared to preserve post-thaw spermatozoa viability in vitro and maintained membrane stability after cryopreservation. (C) 2003 Elsevier Inc. All rights reserved.