GROWTH, BODY COMPOSITION AND ANTIOXIDANT ENZYMES PROFILE OF OREOCHROMIS NILOTICUS AS INFLUENCED BY VITAMIN E FORTIFIED FEED  

Vitamin E is used for the fortification of feed to improve growth, resistance to stress and disease as well as survival of fish while improving specific and non-specific immune response. The present experiment is therefore planned to monitor growth, body composition and antioxidant enzyme profile in Nile tilapia (Oreochromis niloticus) using 0, 100 and 200 mg vitamin E per kg of feed. Nile tilapia received the vitamin E fortified feed @ 6% of body weight for 30 days in the glass aquaria having 70 liter of water with three replicates. Growth in terms of body weight and body composition in terms of moisture, protein, fats, ash and carbohydrates was recorded. The activity of two antioxidant enzymes viz; catalases and superoxide dismutase was recorded in the gills and liver of experimental fish. Fortification of feed with 100 mg vitamin E per kg of feed resulted in maximum growth (i.e. 8.63 ± 0.14 gm net gain in body weight) followed by control (7.87± 0.12 gm net gain in body weight) and 200 mg vitamin E treatment (7.31±0.13 gm net gain in body weight) at the end of experiment. The protein contents in meat of fish was also maximum in T1 (100 mg vitamin E /kg feed) i.e. 20.40 % while lowest in control i.e. 19.79 %. Steady but statistically significant increase in fat contents of fish meat was recorded as vitamin E increment in feed increased. Activity of both selected antioxidant enzymes i.e. catalases and superoxide dismutase remained significant statistically either in case of vitamin E concentration or in selected organs i.e. liver and gills.  Activity of both selected antioxidant enzymes i.e. catalases and superoxide dismutase recorded as maximum under T2 (200 mg vitamin E /kg feed) in both organs as in liver (480.05 & 625.73 u/ml) and gills (249.13 & 638.21 u/ml). Catalase showed minimum concentration in liver and gills under T1 (100 mg vitamin E /kg feed) as 318.37 and 224.42 u/ml. Superoxide dismutase activity was minimum in case of liver (588.96 u/ml) under control treatment and in case if gills under treatment 1 (617.07 u/ml). From the study it was concluded that increment in vitamin E in feed enhanced the immune response significantly in terms of catalases and superoxide dismutase activity in liver and gills. With reference to growth and protein contents of meat of Nile tilapia, fortification of feed with the 100 mg vitamin E resulted in best outcomes.