Histopathological alterations induced by diazinon in rainbow trout [oncorhynchus mykiss]

Diazinon is a moderately persistent organ phosphorus pesticide largely used in agriculture. The purpose of this study was to evaluate the histopathological damages induced by diazinon in gills, kidney, spleen, and intestine tissues of rainbow trout, Oncorhynchus mykiss. The fishes were exposed to sub-lethal concentrations of diazinon [0.1 and 0.2 mg/L] for a period of 28 days. Tissues analyzed by a microscope were normal in the control group. The histological alterations in gills were characterized by epithelial hyperplasia, necrosis of epithelial filament and lamellar fusion, edema and curling of secondary lamellae. Glomerular lesions, shrinking of the glomerulus and enlargement of space inside Bowman's capsule, dwindling of the tubular lumen, degeneration and necrosis of renal tubules were observed in the kidney tissue of the exposed fish. The spleen tissue showed disorder in ellipsoids cellular and deposition hemosiderin in melanomacrophage centers. Exfoliate of mucosal epithelium, lymphocyte infiltration to lamina propria, reduction of the elastic properties and capillary bleeding were seen in intestine tissue of fish exposed to diazinon. In conclusion, these results indicate the existence of a direct relationship between the pollution of ecosystems by organ phosphorus pesticides such as diazinon and histopathological disorders in different tissues of exposed fishes

Effect of sub-lethal diazinon concentrations on blood plasma biochemistry

Diazinon is commonly used for pest control in the agricultural fields surrounding freshwater reservoirs. This study was conducted to determine the chronic toxicity of organophosphorous pesticide and its effects on some hematological parameters and biochemical blood plasma profiles of common carp, Cyprinus carpio. Diazinon was applied at concentrations of 60 and 120 micro g/L preparations in 10, 20 and 30 days since the experiments were initiated. The experimental groups showed significantly lower values [p < 0.05] of erythrocyte count, haemoglobin content, haematocrit, leucocytes, Lymphocyte and monocyte, as well as in alkaline phosphatases and significantly higher [p<0.05] values of plasma glucose, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, neutrophile and eosinophile compared to the control group. There was not significant difference in value of total protein [p< 0.05] in the experimental groups and control group. Values of MCV, MCH and MCHC of experimental species were compared to the control groups. The results of examinations of the biochemical blood plasma profile indicate a marked neurotoxic effect of diazinon in fishes. Changes in values of both erythrocyte and leukocyte profile after exposure to diazinon-based preparation may be referred to disruption of haematopoiesis as well as to a decrease on non-specific immunity of the fish