Bioaccumulation And Influence Of Cadmium Chloride On Histology Of Muscles And Gills In Nile Tilapia (Oreochromis Niloticus)

Abstract

Heavy metals Show a heterogeneous pattern of accumulation in different organs. Cadmium is an essential inorganic
toxicant widely distributed in the environment. The current study evaluates the histopathological changes in Nile tilapia (Oreochromis niloticus) treated with different concentration of cadmium chloride. Fish was stocked in triplicate (control group, T1, T2). The two groups T1 and T2 are exposed to sub-lethal doses 1/5th(2.96mg/L) and 1/10th(1.48mg/L) of LC50(14.8mg/L) of CdCl2 for 21 days. Fish was dissected, gills and muscle tissues were removed. Histological examination of gills specimen revealed that CdCl2 exposure substantially damages histopathological profile as evident from primary lamellae dilation, secondary lamellae splitting, detached sub lamellae, and inter lamellar cells hyperplasia. It leads to mild edema, acute inflammation, and blood vessels congestion was observed in CdC12 induced group as compared to control group. However, no necrosis and hemorrhage of gills tissues were seen. The histopathology of treated fish muscle was revealed distorted muscle orientation and hypotrophy of muscle volume with splitting muscle fibers. Additionally, edema, necrosis, focal muscles, inflammation, muscle deposition, and muscle degeneration observed in the CdCl2 intoxicated group as compared to control group. It is concluded that exposure with high concentration of CdCl2 causes histopathological alterations in Oreochromis niloticus.