Cell size, number and density in the retina ganglion cell layer of Pekin duck retina at different embryonic age

Changes in cell size, number and density of the ganglion cell layer（GCL）of the Pekin duck retina were studied by using the methods of Nissl-staining and Scion Image picture processing at embryonic age day-11，14，17，20，23 and 26. The result indicated that the cells in GCL were small and round uniformly at E11 and E14. The large cells were first found at E17. From E11 to E26, cell size was increased 1.97-fold in the central area (CA) and 3.1-fold in the temple periphery (TP), and there was significant difference among all embryonic ages. During the growth and development of embryo, the total number of cells in GCL was increased to 2.03×106 cells at E17, and then decreased significantly with age. Differentiation of the central-peripheral gradient in cell density has been performed at E11. Cell density in CA was up to the maximal value (2.54×104 cells/mm2) at E17 and then decreased. However, cell density was decreased constantly in the peripheral area, especially in TP. In conclusion, E17 is the most important point for the retina during the embryonic developmental of Pekin duck, accompanying changes in cell size, number and density in GCL [Acta Zoologica Sinica 54(6): 1082 – 1088, 2008].