Effect of Dietary Protein and Lipid Levels on the Reproductive Performance and Body Composition of Angelfish, Pterophyllum scalare (Schultze, 1823)

A study to determine the effect of increasing levels of dietary protein and lipid on Pterophyllum scalare was carried out using twelve semi-purified diets varying in dietary protein (P) and lipid (L) levels (48P8L, 48P12L, 48P16L, 50P8L, 50P12L, 50P16L, 52P8L, 52P12L, 52P16L, 54P8L, 54P12L and 54P16L). Broodstock performance was evaluated based on relative fecundity, fertilization rate, hatching rate, egg size, spawning interval, egg and body composition of P. scalare broodstock. Egg production was highest from fish fed with 50P12L, 52P12L and 52P16L diets. Fish fed the 50P12L and 52P12L diets tended to spawn at shorter intervals. Relative fecundity, fertilization rate, hatching rate, egg size and relative hatchling number, were all significantly higher on diets containing 52% protein than at lower levels. There was no significant difference in hatchling length but hatchling weight differed significantly (P < 0.05) with dietary protein and lipid levels. The protein content of fish and eggs was also influenced (P < 0.05) by dietary protein and lipid levels. It is therefore suggested that in P. scalare broodstock fed with 50-52% protein and 12% lipid, reproductive performance, egg and larval quality improved compared with other diets.