Evaluation of Practical Feed Formulations and Dietary Supplements for Red Swamp Crayfish

Three 6 wk feeding trials were conducted with juvenile red swamp crayfish Procambarus clarkii in a flow-through culture system to evaluate practical feed formulations and specific dietary sup plements. Diets were formulated to contain 30% crude protein from various practical ingredients with or without supplemental cholesterol, lecithin, astaxanthin, vitamin premix and mineral premix. Peanut meal consistently provided inferior weight gain of crayfish compared to soybean, fish and shrimp meals, and a combination of soybean meal and fish meal supported the most rapid weight gain. Supplementation of 1.0% cholesterol did not enhance crayfish weight gain compared to a basal diet, whereas supplementation of 6% lecithin improved weight gain. Astaxanthin supplementation at 13 mg/kg diet marginally improved crayfish weight gain compared to a diet containing 1% beta-carotene. Deletion of a complete vitamin premix impaired crayfish weight gain while deletion of a trace mineral premix did not. Results from this study indicate that protein quality significantly influenced weight gain of crayfish in a flow-through culture system, and supplernentation of a complete vitamin premix was most critical.