Effects of dietary cholesterol on growth, survival and body composition of juvenile abalone Haliotis discus hannai Ino

An experiment was conducted to determine the dietary cholesterol requirement of juvenile abalone Haliotis discus hannai. Eight isoenergetic (18.15–18.61 kJ/g) and isonitrogenous (29.00–29.78% protein) diets, supplemented with 0.00, 0.15, 0.30, 0.45, 0.60, 0.75, 0.90 and 1.05% cholesterol were evaluated. Juvenile abalone (initial weight: 0.67–0.72 g) were reared in a flow-through water system for 24 weeks. During the feeding trial, water temperature was maintained at 14–17 °C, salinity 31–33, pH 7.4–7.9. Abalone fed diet without cholesterol supplementation had the lowest weight gain ratio (WGR, 356.70%). Survival ranged from 98.52 to 100.00% and was not significantly different among treatments. There were no significant effects of dietary cholesterol on composition and cholesterol concentration in the muscle and viscera of abalone. Based on data of WGR using broken-line analysis, the optimal dietary cholesterol requirement of juvenile abalone was found to be 0.23%.