author(s)
Binod Kalita, Hemanta Pokhrel and Inam Akhtar Hussain

abstract
Appearance, development and organization of Melano-Macrophage Centres (MMCs) in Indian major carps. (Catla catla, Labeo rohita and Cirrhinus mrigala) was studied for a period of 360 days. Small patches of melanin-containing cells appeared at about 60 days old in the spleen and kidney of these species. The density of splenic and renal MMCs was observed to increase steadily with age of the fish. The MMCs were less compact and smaller in size in the trunk kidney than in the spleen. The size of the MMCs was highly variable within the fish in the same organ and these centres were distributed in the spleen, pronephros, and mesonephros and opisthonephros but not observed in the liver and thymus in the species. The existence of morphological similarity was observed with respect to size, shape and distribution of MMCs in all the three species of Indian major carps.