- Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences
Langeland, Markus; Andersson, Kristina; Lundh, Torbjörn; Lindberg, Jan Erik
The aim of this study was to estimate the optimum dietary lysine requirement of juvenile Eura-sian perch (Perca fluviatalis), and to investigate the influence of different dietary lysine levels on growth, carcass composition, somatic indices and haematocrit value. A total of 240 juvenile perch was included in a 12-week feeding study. Based on the whole body amino acid profile of in total 48 perch of three different weight groups, eight semi-purified diets containing graded levels of lysine (L1-L8) were produced. The diets contained approximately 12% crude lipid and 40% crude protein and the lysine level varied from 12.2 (L1) to 24.3 (L8) g kg-1 dry matter (DM). Approximately 40% of the total nitrogen content in the diets was in the form of protein-bound amino acids. The ideal protein concept was applied for estimation of the amino acid re-quirements. Fish fed diets L5-L8 (18.3-24.3 g lysine kg-1 DM) had higher final body weight, weight gain, protein gain and specific growth rate (P<0.001) than fish fed diets L1-L4 (12.2-17.3 g lysine kg-1 DM). Dietary lysine level did not significantly affect intraperitoneal fat, haematocrit value and carcass composition. The results indicate that the lowest lysine level re-quired for optimal growth performance in Eurasian perch is 18.3 g lysine kg-1 DM.
Eurasian perch; Lysine requirement; Essential amino acids; Growth; body composition; Ideal protein
Journal of FisheriesSciences.com
2014, Volume: 8, number: 2, pages: 161-175
Fish and Aquacultural Science