Pattern of Distribution of Epinephrine and Norepinephrinecellsin the Adrenal Gland of Kuttanad Ducks (Anas Platyrhynchos Domesticus) during Post Hatch Period

Abstract

The study was conducted to understand the pattern of distribution of adrenaline and noradrenaline cells in the adrenal gland of Kuttanad ducks (Anas platyrhynchos domesticus) during post hatch period. Chromaffin tissue consisted of lightly and darkly stained polygonal cells. Light cells were larger in size and possessed a large spherical vesicular nucleus, while the darker cells were smaller and more in number. By Woods staining technique, large cells could be identified as the epinephrine or adrenaline cells and the small cells, the norepinephrine or noradrenaline cells. At 10 weeks of age, among the chromaffin cells, norepinephrine cells were found to be predominating.  At 12 weeks, the adrenaline and noradrenaline cells showed numerous granules.  At 16 weeks of age, when the birds started laying eggs, among the chromaffin cells, majority was norepinephrine cells. The norepinephrine cells possessed small condensed blue coloured nucleus without a distinct nucleolus while the brown epinephrine cells possessed larger transparent vesicular nucleus in Wood's staining and were distributed more towards the central portion of the chromaffin islet. At 18 weeks, yellow norepinephrine cells were concentrated more towards the subcapsular area and many chromaffin islets were distributed in the centre of the gland crowding around the venous sinuses.  At 22 weeks, number of ganglion cells (both large and small) was greatly increased.