Multinucleated erythroid cells in blood of golden hamster embryos

Blood smears of 11 and 13-day-old embryos (20) and newborns (10) of golden hamsters were analysed. The smears were stained with brilliant cresyl blue in a moist chamber for 5--7 min. About 2--6 thousand cells were counted in 200 visual fields. By means of an ocular micrometer MOB-1 the diameters of 300 cells were measured and the curves on cell distribution were plotted according to the diameters. It was found that the blood of 11-day-old golden hamster embryos contained about 8% of binuclear and sixnuclear megaloblasts, and that of 13-day-old embryos--about 2.5% of binuclear and sixnuclear erythroblasts and megablasts of the second generation. In the bloood of newborn hamster polynuclear cells are absent.