Critical nutritional requirements of juvenile yellow perch

Production of yellow perch (Perca flavescens) has increased in the North Central region of the United States despite the paucity of information on nutritional requirements of this new culture species. Thus, feeding studies were conducted to quantify key nutritional requirements of juvenile yellow perch. The studies included determination of the dietary arginine, lysine, total sulfur amino acid (TSAA) and choline requirements. The basal diet was formulated to provide approximately 33 g crude protein/100 g diet from casein, gelatin and crystalline amino acids, and 6 or 12 g lipid/100 g diet supplied by menhaden oil. In each amino acid requirement experiment, graded levels of the test amino acid were added to the basal diet at the expense of L-glutamic acid. In the choline requirement experiment, increasing levels of choline chloride were added to the basal diet at the expense of cellulose. Dietary treatments were fed to triplicate or quadruplicate groups of 15 fish for a minimum of 8 wk. Broken-line analysis of weight gain, feed efficiency, and feed intake data indicated the dietary requirements of juvenile yellow perch were 1.3 g arginine/100 g diet (3.9 g arginine/100 g dietary protein), 1.3 g lysine/100 g diet (4.0 g lysine/100 g dietary protein), and 600 mg choline/kg diet. Furthermore, growth response and body composition data indicated that phosphatidylcholine (PC) could meet the dietary choline requirement of this species. Results of the TSAA studies indicated that the dietary methionine requirement was 1.0–1.1 g methionine/100 g diet (3.1–3.4 g TSAA/100 g dietary protein), that cyst(e)ine could spare approximately 51% of the methionine requirement of perch, and that the dietary sulfur amino acid requirement was 0.85–1.0 g TSAA/100 g diet (2.5–3.0 g TSAA/100 g dietary protein) in diets containing the maximum cyst(e)ine replacement value for methionine. Data obtained in these studies should be useful in developing cost effective diets that meet the nutritional needs of yellow perch