Ligula intestinalis originally is belongs to Cestoda parasite that infests a range of fish family especially Cyprinidae. It is also a zoonosis parasite that affects fish and probably human health. This study tried to isolate L. intestinalis from Sea bream (Abramis brama Orientalis), an species classified in family, Cyprinidae, from Caspian Sea. Sixty Sea bream were caught from Caspian Sea, Babolsar Fisheries port. Among that, 26.66% were infected with L. intestinalis. The tissues of infected fishes including gonads, liver and kidney were examined for pathological findings. Ovaries changes showed fibrosis, infiltration of inflammatory cells, atrophy of oocytes; testicular hyperemia, necrosis, fibrosis and degeneration; kidneys necrosis, destruction of tubules, vacuolar degeneration; and liver vacuolar degeneration, biliary duct hyperplasia, necrosis, lymphatic vessel dilatation, fibrosis and cholestasis. Considering the effect of L. intestinalis on fish and human health, the prevention programs to disturb the cycle of parasite and more monitoring studies in fish epidemiology especially food fish are recommended.
