Dietary Protein Requirement of Southern Flounder, Paralichthyslethostigma

摘要

A 12-week feeding trial was conducted to determine the protein requirement of southern flounder, Paralichthys lethostigma. Diets varied crude protein (CP) levels (35, 40, 45, 50, 55, and 60%), while dietary lipid levels were held constant at 14% and dextrin was included to maintain diets isocaloric, with all diets providing 370 kcal available energy/100g diet. Weight gain (percent of initial weight) ranged from 292-394% and was not significantly affected by dietary protein levels. Feed efficiency ratio values (g gain/g fed) ranged between 0.40-0.54 (P > 0.05). Protein efficiency ratio (g weight gained/g dietary protein fed) did not differ significantly (P > 0.05) between groups (0.9-1.27). The protein requirement was determined by relating percent increase in weight gain with dietary protein levels utilizing two statistical methodologies: least squares regression (protein requirement: 50.3% CP) and a four-parameter logistic growth curve (50.8% CP).