EFFECTS OF DIFFERENT DIETARY VITAMIN E LEVELS ON GROWTH PERFORMANCE AND SURVIVAL OF INDIAN BUTTER CATFISH Ompok bimaculatus FINGERLINGS

Vitamin E is a fat soluble vitamin which plays an important role in growth, immunity and survival of fish. A sixty-day feeding trial was conducted to determine the dietary vitamin E requirement for growth of Indian butter catfish, Ompok bimaculatus fingerlings. Five iso-nitrogenous (35%) and iso-energetic semi-purified diets with different levels of α-tocopherol acetate such as control (0), D1 (100), D2 (150), D3 (200) and D4 (250) mg kg^-1 of diet were fed to O. bimaculatus fingerlings (average weight 2.21 ± 0.02 g; 30 healthy fish per replicate) in triplicate groups following a completely randomized design. Each group was fed to satiation twice a day for 60 days. Significant differences were observed in growth performance with different dietary vitamin E levels (P<0.05). Maximum weight gain (386.21±2.63%), specific growth rate (2.64±0.01% day^-1) and protein efficiency ratio (PER) (2.42±0.05) were found in fishes fed with 100 mg α-tocopherol acetate per kg diet, supported by best feed and protein intake per fish (P<0.05) and lower Feed conversion ratio (FCR) value (Table 1). Hence, it may be concluded that the vitamin E requirement of O. bimaculatus fingerling is 100 mg kg^-1 diet as indicated by better growth performance and feed utilisation. However, using broken line regression analysis, the maximum growth was found to be at 104.5 mg α-tocopherol acetate per kg diet. Our results will be helpful for the formulation of cost-effective α-tocopherol acetate incorporated diets for Indian Butter catfish, O. bimaculatus.