The Effect of Glycerol Equilibration Time on the Freezing of Bovine Spermatozoa in Egg Yolk–Sodium Citrate and Skimmilk Semen Extenders

Abstract

A study was made of the effect of glycerol equilibration time on the freezing of bovine spermatozoa in egg yolk-citrate and skimmilk extenders. An analysis of variance indicated that the differences in survival motility between 0.5-hour and 18-hour equilibration times were significant at the 5% level and were in favor of the 0.5-hour period. This should not be construed to mean that a 0.5-hour equilibration time is optimal for all semen, since it was found that semen from several bulls responded better to an 18-hour period. There is considerable variation among bulls in the ability of their semen to freeze successfully.