EFFECT OF VARYING DIETARY PROTEIN LEVEL ON GROWTH AND NUTRIENT UTILISATION OF GENETICALLY IMPROVED FARMED TILAPIA (GIFT) JUVENILES REARED IN INLAND SALINE WATER

The growing interest for inland saline aquaculture can help to utilize the vast resource of salt affected areas and trigger towards variety of aquafarming activities. Among the different nutrients, dietary protein is the most crucial factor for the success of the fish culture both in terms of cost of production and growth of the fish. There is lack of information on optimum dietary protein level in the diet of GIFT reared in Inland Saline Water. Therefore, a 30 days feeding trial was conducted to determine the effect of dietary crude protein (CP) level on growth and nutrient utilisation of GIFT reared in Inland Saline Water. Seven iso-energetic (4000 Kcal DE/ kg) and hetero-nitrogenous purified diets namely T20 (20% CP), T25 (25% CP), T30 (30% CP), T35(35% CP), T40 (40% CP), T45 (45% CP), and T50 (50% CP) were formulated and prepared. Three hundred and fifteen (315) acclimated GIFT juveniles (average body weight 2.68±0.01g) were randomly distributed in seven treatment groups with triplicates following completely randomized design. Stocking density was 15 fish per tank (300 L capacity, 200 L water volume) and the salinity of water was maintained at 10 ppt throughout the experimental period. Experimental fish were fed to respective diets at satiation level thrice daily. Results indicated that weight gain (WG) %, specific growth rate (SGR), daily growth rate (DGR), and feed efficiency ratio (FER) were significantly higher (P <0.05) and feed conversion ratio (FCR) was significantly lower (P <0.05) in fish fed diets containing 40 and 45% CP.