In the former study, 1.0 M lactamide, acetamide and DMSO were highly cryoprotective, and 1.0 M glycerol resulted in extremely low motility after thawing in the New Zealand white rabbit. Smith and Polge [27] also reported that less than 2% of the oocytes recovered from females inseminated with rabbit semen frozen in the presence of glycerol were fertilized. Although glycerol has been used successfully to freeze spermatozoa from several species, it is not an effective cryoprotectant for sperm freezing in the laboratory rabbit. The discovery of the cryoprotective actions of glycerol has allowed cryopreservation of spermatozoa and although hundreds of potential cryoprotectants have subsequently been tested, glyc- erol has remained, almost without exception, the cryoprotectant of choice for spermatozoa from almost all species, especially in domesticated animals