A Comparative Study in some Morphological and Histological Features of the Liver in Gull (Laruscanus) and Mallard duck (Anas platyrhynchos)

This study was conducted to evaluate the morphological and histological features of the liver in two species of birds that vary in their food habitats; gull and mallard. Histomorphologically, the liver in these species is composed of the left (small) and right (big) lobes and the right lobe in gull was subdivided into two parts. Histologically, fibrous capsule covered the liver parenchyma without any clearly defined lobules in both species. The hepatic architecture comprised of hepatic cells organized as irregular plates or cords, which radiated around the central vein and the blood sinusoids distributed among those plates. The portal triads, enclosed by fibrous connective tissue, contains branch of hepatic artery, bile duct andportal vein. Several histological structures shown variations in both species including; capsule appeared thinner in mallard than in gull with mean thickness of 80.52±6.38µm and 86.23± 7.14µm respectively, and the diameters of central veins differed where mallard has 461.15 ± 11.25 µm and gull carried 387.42 ± 9.06 µm size. These morphological and histological features highlight fundamental differences in these species can be used as species-identification markers.