Growth and body composition of juvenile red drum (Sciaenops ocellatus) fed diets containing lecithin and supplemental choline Conference Paper uri icon

abstract

  • Two factorial experiments were conducted for 6 weeks each to determine the effects of supplemental choline and lecithin in the diet of juvenile red drum (Sciaenops ocellatus). Four isocaloric diets were formulated utilizing solvent-extracted menhaden fish meal which provided 744 mg choline kg-1 diet. Menhaden oil was added to provide a total of 7% lipid in the basal diet. In the first experiment, the basal diet also contained 3000 mg choline bitartrate kg-1 diet as part of a complete vitamin premix. Three other diets were formulated by the addition of either lecithin (soybean refined) at 4% of diet in place of menhaden oil, supplemental choline bitartrate at 3000 mg kg-1 diet, or a combination of 4% lecithin and 3000 mg choline bitartrate kg-1 diet. The diets were fed to triplicate groups of juvenile red drum initially averaging 2.6 g per fish in aquaria containing brackish water (6). Factorial analysis of variance indicated no significant main effects on weight gain, although the lecithin effect approached significance (P = 0.07). Lecithin did significantly (P < 0.05) improve feed efficiency. Dietary effects on biological indices [muscle ratio (MR), hepatosomatic index (HSI), and intraperitoneal fat (IPF) ratio] were limited to significant effects of lecithin, choline and their interaction on lowering HSI. Fish fed the diets containing supplemental choline had significantly lower total lipid in liver compared with fish fed diets without supplemental choline, while fish fed supplemental lecithin had significantly higher lipid in the liver. Total lipid in muscle was significantly increased by supplemental choline. The second feeding trial was similar to the first except the vitamin premix contained no choline and supplemental choline was provided in the form of choline chloride. Weight gain and feed efficiency of juvenile red drum were significantly increased by lecithin. Dietary lecithin also had significant effects on MR, HSI and IPF ratio values, while supplemental choline had no effect on these indices. Dietary effects on muscle and liver lipid were similar to those observed in the first experiment with choline significantly increasing muscle lipid and lowering liver lipid. Lecithin significantly increased total lipid in liver of red drum. Thus, in these two experiments, the addition of lecithin generally improved weight gain and feed efficiency and increased liver lipid in juvenile red drum; whereas supplemental choline appeared to shift lipid towards the muscle and IPF and away from the liver.

published proceedings

  • AQUACULTURE

author list (cited authors)

  • Craig, S. R., & Gatlin, D. M.

citation count

  • 56

complete list of authors

  • Craig, SR||Gatlin, DM

publication date

  • May 1997