This work aimed to evaluate the antidotal role of allicin and/or betaine versus experimental Cd toxicity in terms of restoring Cd-provoked changes in the circulating oxidative biomarkers together with biochemical indices of tissue abnormalities in common carp. 150 healthy common carp were subdivided into five equal groups. Group 1 fish (control) was reared in normal freshwater. Fish in other groups were exposed to 5 mg/L cadmium chloride in water for 15 days. Group 3 fish received diet supplemented with betaine (30 mg/kg BW); Group 4 fish received diet supplemented with allicin (15 mg/ kg BW) and in group 5, fish food was supplemented with both betaine and allicin. Cd exposure caused significant decline in circulating SOD, catalase, GSH and FRAP as well as a rise in MDA values. Plasma levels of ALT, GGT, ALP, glucose, urea and creatinine also showed significant increase in fish treated with cadmium compared with controls. However, allicin and/or betaine supplementation had been somewhat fortunate in recovering Cd-provoked shifts in the circulating oxidative biomarkers and biochemical indicators of tissue abnormalities in common carp which may be relevant to antioxidant properties of these compounds as well as metal-chelating and methyl-donating abilities of allicin and betaine respectively. Moreover, combination of allicin and betaine stands outs as the most effective approach upon Cd poisoning. However, explanation of the precise molecular mechanisms of their modulating effects against Cd poisoning as well as their optimal dosage in various exposure durations and toxicant concentrations requires further study. K E Y W O R D S allicin, antioxidants, betaine, blood biomarkers, cadmium, Cyprinus carpio

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