CRYOPRESERVATION OF SPERMATOZOA FROM CYNOMOLGUS MONKEYS (MACACA-FASCICULARIS)

Fertilization of eggs from cynomolgus monkeys (Macaca fascicularis) wa s achieved in vitro using frozen-thawed spermatozoa. The best sperm su rvival rate was obtained after freezing spermatozoa in a semen-dilutin g medium (TTE: Tes, Tris, egg yolk base) containing 5% glycerol with 3 0 min equilibrium time. Although frozen-thawed spermatozoa could ferti lize eggs in vitro and some of the fertilized eggs developed into blas tocysts or hatched blastocysts, a sperm fertility assay using salt-sto red eggs indicated that frozen-thawed spermatozoa had a shorter lifesp an in capacitation medium than did fresh, unfrozen spermatozoa. This m ay be attributable to damage to their plasma membranes.