CRYOSURVIVAL OF RAM SPERMATOZOA IN HYPERTONIC AND ISOTONIC DILUENTS

Abstract
The cryosurvival (percentage of motile spermatozoa and rate of foward progression) of ram spermatozoa after freezing in hypertonic and isotonic diluents containing a buffered dextran-sugar combination or buffered dextran-sugar plus egg yolk was compared immediately after thawing and after incubation at 39° for 60 min. Cryosurvival of spermatozoa was comparable in both diluents. However, the cryosurvival of spermatozoa was increased significantly in hypertonic diluents compared with that in isotonic diluents, regardless of their composition. Key words: Spermatozoa, sheep, cryosurvival, diluents