Dietary cholesterol and lecithin have limited effects on growth and body composition of hybrid striped bass (Morone chrysops x M-saxatilis)

The effects of cholesterol and lecithin on growth and body composition of j uvenile hybrid striped bass (Morone chrysops x M. saxatilis) were investiga ted by feeding juvenile hybrids (initial weight 5.0 g) diets containing cho lesterol at either 0 or 1% and lecithin at either 0, 2, 4, or 6% in a 2 x 4 factorial design. Each of the eight diets was fed to fish in triplicate 38 -L aquaria maintained as a brackish water recirculating system for 8 weeks. Weight gain, feed efficiency, muscle ratio and hepatosomatic index were no t significantly (P > 0.05) affected by dietary supplementation of cholester ol or lecithin. Supplementation of the diet with lecithin at 4 and 6% signi ficantly (P < 0.05) decreased intraperitoneal fat accumulation regardless o f dietary cholesterol level. Neither muscle nor liver lipid levels were sig nificantly altered by dietary supplementation of cholesterol or lecithin al though both liver and plasma lipid classes were affected. Dietary cholester ol decreased concentrations of liver and plasma free fatty acids and liver phospholipids while increasing concentrations of liver triglycerides and pl asma phospholipids. Dietary lecithin did not consistently affect plasma and liver lipid classes although changes in phospholipid levels approaching si gnificance (P = 0.0502 and P = 0.0513, respectively) were observed. Thus it is concluded that dietary supplementation with cholesterol or lecithin had no substantial beneficial effects on growth or body composition of juvenil e hybrid striped bass.