Hoechst 33258 labeling chromatin patterns in immature rat oocytes. Full projections of z-stacks from representative oocytes in each category are represented depicting NSN1 (a), SN2 (b), CHR3 (c), and CCM4 (d). All images magnified 100× from projections that reveal the total chromatin content of control samples. 1NSN—Non-Surrounded Nucleolus, 2SN—Surrounded Nucleolus, 3CHR—Chromosomes, 4CCM—Central Chromatin Mass