PROTEIN REQUIREMENT AND OPTIMUM RATIO OF DIETARY PROTEIN TO ENERGY FOR JUVENILE CHINESE STURGEON,Acipenser sinensis
WEN Xiao Bo KU Yao Mei LUO Jing Bo (Department of Animal Science, Hubei Agriculture College, Jingzhou, 434025)
The optimum protein requirement and ratio of protein to energy for juvenile Chinese sturgeon (body weight, 8.37 g±0.79 g) were determined using practical diets in a 5×5 factorial experiments. Five protein levels (25, 30, 35, 40 or 45) and five dextrin levels (4, 13, 24, 35 or 43) at a fixed lipid level of 3% were tested. The ratios of the experimental diets ranged from 15.41 to 37.05 ng protein/J. The experimental fish were reared for 8 weeks in 150 liter flow through tanks with groundwater at 22.3～25.1 ℃. Based on calculating weight gain, food conversion rate and protein efficiency rate, the experimental results indicated the protein requirement and optimum ratio of dietary protein to energy for juvenile Chinese sturgeon were 35.7%～41.8%, and 21.85～30.05 ng protein/J respectively. The diet containing 40.3% protein and 1.44×107J dietary calorie/kg diet with the ratio of protein to energy of 27.85 ng protein/J was found to be optimum for juvenile Chinese sturgeon under the experimental conditions used in the study.