RESUMO
Fluoride is the organic and inorganic compound of the element fluorine, has detrimental effect to all animals including fish at higher concentration. Ground water with elevated concentration of fluoride is a major global problem including India. On the other hand, Morinda citrifolia (also called ‘Noni’ in Polynesia) is a medicinal plant, has antioxidative, anti-inflammatory and immunostimulatory properties. The ameliorating effect of M. citrifolia fruit extract dietary supplementation against fluoride induced toxicity on the growth performance, haematological parameters, and fluoride accumulation in the muscular tissue was investigated in the freshwater fish, Cyprinus carpio L. for 35 days in triplicate. One hundred and twenty acclimated C. carpio fingerlings were randomly allocated into five experimental groups (Groups I, II, III, IV and V) each with 24 fish divided into three replicates (eight fish/replicate). Group I (Control) and II (Toxic control or negative control) were provided with basal/control diet, whereas groups III, IV, and V were provided with 0.25% (2.5 g/kg), 0.50% (5.0 g/kg) and 0.75% (7.5 g/kg) M. citrifolia fruit extract supplemented diet respectively. All groups except for group I were exposed to 10% of the LC50 of fluoride. Selected growth and haematological parameters were estimated. The fluoride content in the muscular tissue of fish was also estimated following SPADNS method. Results revealed that exposure of sublethal concentration of fluoride significantly (P <0.05) reduced the growth performance and haematological parameters in Gr. II (toxic control) compared to the Gr. I (control). However, M. citrifolia dietary supplementation significantly (P <0.05) improved fluoride induced alteration of growth performance and haematological parameters of fish in the groups III, IV and V compared to Gr. II. Morinda citrifolia fruit extract dietary supplementation also significantly (P <0.05) decreased the accumulation fluoride in the muscular tissue of fish in groups III, IV and V compared to the Gr. II (toxic control). In conclusion, M. citrifolia dietary supplementation ameliorates the fluoride toxicity by preventing the accumulation of fluoride in the muscular tissue of the fish. The M. citrifolia dietary supplementation at 0.25% showed the best response, hence it is considered as the optimum dose.
RESUMO
Fluoride is a trace element which has beneficial effect at lower concentration but detrimental at higher concentration. The fluoride contamination in ground water is a major global problem. Similarly, aluminium is the most abundant metal of the earth, highly toxic to all organisms. In the present study, we investigated the acute toxicity of fluoride and aluminium on three month old fingerlings of Cyprinus carpio L. in hard water (Hardness 125 mg/L of CaCO3) under static renewal bioassay. The 96 h LC50 value of the fluoride and aluminium were 675.615 and 224.214 mg/L, respectively. There was a significant correlation (P <0.01) between mortality rate of C. carpio with all concentrations of fluoride as well as aluminium. The exposure time (24, 48, 72 and 96 h) and different concentration of fluoride (680, 684, 686 and 692 mg/L) and aluminium (228, 229, 231 and 232 mg/L) was also significantly correlated (P <0.05). The different abnormal behaviour displayed by the fluoride and aluminium exposed fishes were erratic swimming movements, rapid opercular activity and excessive secretion of mucous. The safe level of concentrations of fluoride and aluminium were 6.75 and 2.24 µg/L, respectively. The LC50 values of fluoride and aluminium of the present study may be useful in deriving water quality standards in West Bengal.