Effect of Some Heavy Metal on Histological Structural of Gills and Liver of Rabbit Fish (Siganus rivulatus) from Two Sites Along Red Sea Coast, SUDAN.

The present research aimed to detect the levels of heavy metals lead (Pb) and cadmium (Cd) in Sudanese Red Sea water, sediment, wild algae and their effects on histological structural of the gills and liver of the fish Siganus rivulatus. The wild herbivores rabbit fish (Siganus rivulatus) Forssk?l (Teleostei, Siganidae) were caught from two sites, Dongnab and Suakin on Sudanese Red Sea Coast during February 2012 - January 2013. The water and sediment of the polluted site (Suakin), contained high level of lead (Pb) compare with Dongnab (control) site where (Cd) concentration was similar in both. Fishes caught from Suakin site (polluted) showed a low values in condition factor, liver-somatic and gonado-somatic index as compared with Dongnab (control) fishes. Contrarily, bioaccumulations factor of lead (Pb) in fish organs from Suakin site recorded a high level compare with Dongnab fishes. Histopathological investigation of gills and liver showed that most Siganus rivulatus caught from Dongnab site revealed normal cellular architectures in gills and liver when compared with that caught from Suakin. In fish gill captured from Suakin site, the most common lesions were epithelial lifting, hyperplasia and hypertrophy of the respiratory epithelium, lamellar fusion and aneurysms in the gills. While the liver shown hepatocytes with hypertrophy, cytoplasmic and nuclear hypertrophy, melanomacrophage aggregates, bile stagnation and one case of focal necrosis. In addition the lesions were comparatively more severe.