Histo- and Ultrastructural study of the Kidney in three species of Family Rallidae

In birds, the renal system is unique among vertebrate kidneys. Due to vital function of kidneys so the major aim of this examination is to study the histological and ultrastructural structures of kidneys in three water birds; Allen’s Gallinule, Purple Swamphen and Water Rail. These species belong one order, Gruiformes and to one family, Rallidae. Kidneys were removed from the synsacrum and examined histologically. Investigations for light microscopy represented relatively large medulla found in Allen’s Gallinule and showed also that the renal corpuscle was smaller in size and number in Allen’s Gallinule than in Water Rail and Purple Swamphen. In Water Rail and Purple Swamphen collecting tubules were much larger in size and number than in Allen’s Gallinule, they lined by pale cells and cuboidal shape. These differences seem to be the adaptive advantage of species which have to mitigate scarcity of water or excessive evaporative water loss by maximum renal water conservation during migration. On the other hand the electron microscopy study demonstrated that podocytes process was present and large in Purple Swamphen while in Allen’s Gallinule and Water Rail wasn’t visible.