Effeet of Whole Allium cepa Linn. on haematological and biochemical components of Clarias gariepinus Juveniles

Toxicity of onion (Allium cepa) bulb though documented for man and some livestock but few studies in fish. Onion bulb slurry was administered to Clarias gariepinus juveniles at 200,100,25g/kg and 5, 1.5, 0.4g/l through diets and bath. Cellular immune response, humoral changes, liver and kidney function and histopathology of some visceral organs were examined. Proximate composition of the bulb was determined. Onion bulb revealed presence of carbohydrate (7.82%), protein (4.48%), crude fiber (1.68%), iron (0.5mg/l), magnesium (210mg/l), flavonoids (0.46%), saponins (0.28%), tannins (0.95%). PCV, Hb, RBC and WBC were increased in all treatments but values were higher in bath treatment for RBC (3.0×1012/L), PCV (32.7%), Hb (10.7%). MCV, MCH and MCHC showed similar trend. Similar trends as in RBC and WBC were observed in total proteins. Liver and kidney functionality as expressed by ALT, AST, ALP, creatinine and BUN exhibited no damaging effect on organs. Degenerations were observed in the hepatocytes and epithelia cells in the kidney in some treatments especially in bath treatments. In conclusion, onion bulb showed no toxicity in the blood parameters but dose should be considered to avoid harmful effect on liver and kidneys

Lethal Doses and Histopathological Changes in Liver and Kidney of Healthy Clarias gariepinus Sub-adult Exposed to Red Allium cepa Linn. Bulb

Adverse effects of Allium cepa bulb has been well overlooked because it is natural and assumed safe. This study investigated the lethal doses and histopathological changes in liver and kidney of healthy Clarias gariepinus sub-adult exposed to red Allium cepa bulb at varying concentrations (200, 150, 100, 50 and 25 g/kg) of A. cepa via diet and bath (5, 3, 1.5, 0.7 and 0.4 g/L) for two weeks. Specimens were sacrificed, liver and kidneys collected, processed and examined for histopathological changes. Proximate analysis, qualitative and quantitative phytochemistry was determined using standard methods. Brine Shrimp lethality assay (BSLA), LD50 and LC50 of the onion on experimental fish were investigated. Saponins, tannins, phenols, flavonoids and alkaloids were present. LC50 of the onion extract was between 0. 51 mg and 0.64 mg in the BSLA while mean LD50 and LC50 for dietary and bath treatments were 447.1 g/kg and 12.2 g/L. Liver histopathology showed vacuolar degeneration of the hepatocytes and congestion of central vein, while necrosis of the epithelial cells and haemosiderosis were observed in the kidney at high concentrations. Allium cepa is safe in fish when administered in lower dose either through diet or bath exposure but was toxic at high dose