The Influence of some Fractions of Egg Yolk on the Survival of Ram Spermatozoa at 5oC

Abstract

Ram spermatozoa were stored at 5�C in diluents containing various fractions of egg yolk prepared by dialysis, ultrafiltration and ion-exchange chromatography. They survived storage best in the presence of components of egg yolk which were non-dialysable and were not filtered through membranes which retained substances of molecular weight greater than 100000. The substances isolated in peak B of the ion-exchange chromatogram of whole egg yolk described by Seideman et al. (1969) gave greater protection than those from other fractions from this chromatographic system. These data indicate that the low-density lipoprotein fraction of egg yolk is the most likely source of protection to ram spermatozoa against the effects of storage at 5�C.