Abdul Latif

Effect of cadmium chloride and ascorbic acid exposure on the vital organs of freshwater Cyprinid, Labeo rohita

The present study was carried out to evaluate the impact of sub lethal concentrations of heavy metal, cadmium chloride (CdCl 2 .H 2 O), ascorbic acid (vitamin C) and their combination on Labeo rohita . The effect was investigated on the basis of histopathological examinations of control and experimental groups exposed to heavy metal. The acute semi statistical toxicity test for L. rohita revealed 96 h LC 50 value 22.92 mg L -1 for cadmium chloride (CdCl 2 .H 2 O). 215 fingerlings of L. rohita were exposed to three different experimental conditions for 96 h: 11.46 mg L -1 CdCl 2 .H 2 O, or 450 mg Kg -1 ascorbic acid or combination of both these doses. No alterations were observed in gill sections upon comparison between treated and untreated groups. Congestion in sinusoids, fatty change, an increase in Kupffer cells and intrahepatic lymphocytes was observed in CdCl 2 .H 2 O treated group. In kidney sections of heavy metal treated group, degeneration of the glomerular tissue, occlusion in tubular lumen and necrosis were observed. Similar changes but in less severe form, as described above, were observed in the fish exposed to combination of CdCl 2 .H 2 O and ascorbic indicating that ascorbic acid do detoxify the effect of heavy metal to some extant. Our results indicate that cadmium chloride (CdCl 2 .H 2 O), if present in fresh water bodies, may act as strong toxic agent for L. rohita . Keywords: Labeo rohita , cadmium chloride (CdCl 2 .H 2 O), ascorbic acid, histopathology

Effect of various nutrient combinations on growth and body composition of rohu (Labeo rohita )

A total of 80 Labeo rohita fingerlings (mean body weight, 14.7 ± 0.08 g and length, 11.0 ± 0.16 cm) were randomly distributed into four treatments with 20 replicates each, for 60 days, to determine the effect of different feed compositions on the growth and body composition of L. rohita . Four isoenergetic (17.05 ± 0.24 kJ g -1 ) experimental diet viz., control (C), protein rich (PR), fat rich (FR) and carbohydrate rich (CR) were formulated. The proximate composition protein/fat/carbohydrate (P/F/C) of formulated feed were C: P35/F8/C2, PR: P40/F8/C2, FR: P35/F10/C2 and CR: P35/F8/C5. The daily ration size was 5% of fish body weight. The result reveals a highly significant (P≤0.001) difference in specific growth rate (SGR), weight gain (WG) and protein efficiency (PE) among four feeding groups, while differences were significant for feed conversion ratio (FCR). FR showed maximum growth together with high body fat, CR showed low body fat and high proteins. Results indicate that increasing fat up to 9% in diet showed better growth as compared to increasing dietary protein and carbohydrates Key words : Labeo rohita, diet composition, specific growth rate, protein efficiency, body composition.