title: Comparison of Growth Performance and Whole-body Amino Acid Composition in Red Seabream (Pagrus major) Fed Free or Dipeptide Form of Phenylalanine.
abstract: This study was conducted to evaluate the efficacy of the dipeptide form of phenylalanine as a new source of amino acid in terms of growth performance and whole-body amino acid composition in comparison to the free form for red seabream (Pagrus major). Fish (1.46±0.001 g) were fed four isonitrogenous and isocaloric experimental diets containing 0.7 or 1.4% phenylalanine either in free or dipeptide form. A feeding trial was carried out in three replicates and the fish were fed to apparent satiation for six weeks. At the end of the feeding trial, feed intake of fish was influenced by both phenylalanine form and level and significantly higher values were obtained at an inclusion level of 0.7% and by the use of dipeptide form. However, the other growth parameters did not significantly differ among treatments. Whole-body amino acid compositions revealed no significant changes in concentrations of both essential and non-essential amino acids regardless of the increase in phenylalanine levels or the use of its different forms. The finding in this study indicates that juvenile red seabream can utilize dipeptide phenylalanine as efficiently as free form without any undesirable effects on growth performance or whole-body amino acid composition.
authors: Marine and Environmental Research Institute, Jeju National University, Jeju 695-814, Korea .
authors: Sung-Sam
authors: SS
authors: Kim
authors: Marine and Environmental Research Institute, Jeju National University, Jeju 695-814, Korea .
authors: Samad
authors: S
authors: Rahimnejad
authors: Marine and Environmental Research Institute, Jeju National University, Jeju 695-814, Korea .
authors: Jin-Woo
authors: JW
authors: Song
authors: Marine and Environmental Research Institute, Jeju National University, Jeju 695-814, Korea .
authors: Kyeong-Jun
authors: KJ
authors: Lee
keywords: Amino Acid Requirement; Dipeptide; Pagrus major; Phenylalanine