[Demonstration, content and distribution of glycogen in rat ova during segmentation]

A large amount of glycogen can be detected in the cytoplasm of rat eggs; it is evenly distributed in all the cytoplasm of blastomeres and polar globules. During cleavage, eggs show non significative change in glycogen content. This polysaccharide was observed and identified in ultrathin sections. It exists in the form of beta particles.