Soybean‐lecithin supplementation of practical diets for juvenile goldfish (Carassius auratus)

Abstract

AbstractSoybean lecithin, alone or in combination with cod liver or soybean oil, was tested as a supplemental lipid in practical diets for juvenile (0.3 g) goldfish (Carassius auratus). Goldfish were fed one of five diets containing: (i) 4% cod liver oil (CLO); (ii) 2% CLO+2% lecithin (LEC); (iii) 4% soybean oil (SBO); (iv) 2% SBO+2% LEC; (v) 4% LEC. After 6 wk, weight gain and feed efficiency of fish fed diets with 4% LEC were significantly higher than those of fish fed diets with 4% CLO or SBO. Gain and feed efficiency of fish fed diets with combinations of LEC and CLO or SBO were intermediate. Survival and whole‐body lipid were unaffected by diet. Possible mechanisms of performance enhancement in goldfish fed LEC include provision of myoinositol or phosphatidylcholine to support rapid membrane proliferation, enhanced absorption of dietary lipid, and facilitation of lipid transport.