Catacutan, M.R., Coloso, R.M.-1997
Aquaculture, 149 (1-2) : 137-144
Abstract:
Growth performance of juvenile seabass (initial mean body weight, 0.90 +/- 0.04 g) fed varying carbohydrate and lipid levels were determined using practical diets in a 2 x 3 factorial experiment. Two carbohydrate levels (15 and 20%) and three lipid levels (6, 12 and 18%) at a fixed protein level of 42.5% were tested. Dietary energy ranged from 284 to 412 kcal/100 g diet. The fish were reared for 12 weeks in 60 1 flow through tanks with aeration in seawater at 32 parts per thousand and at 26.5-29 degrees C.
Higher weight gains were observed in fish fed diets containing 20% carbohydrate with 12 or 18% lipid. Lowest specific growth rate was observed in fish fed the 15% carbohydrate at 6% lipid. Survival was 100% in all treatments. The feed conversion ratios for fish fed 20% carbohydrate at 12 or 18% lipid, and 15% carbohydrate with 12% lipid were best. Specific growth rate and weight gain did not differ at lower dietary lipid (12-6% or 18-12%) despite an increase of dietary carbohydrate indicating a sparing of lipid by carbohydrate as an energy source. Dietary lipid at 18% (1:1 ratio of cod liver oil and soybean oil) seems to be excessive for seabass. Based on this study, we recommend a carbohydrate level of 20% in diets containing lipid levels ranging from 6 to 18%.
(SE Asian Fisheries Dev Ctr, Dept Aquaculture, Iloilo, Philippines)
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