| The research is on nutrition of Schizothorax Prenanti. Nutrient contents of the muscle of Schizothorax prenanti at three different stages were analysised and its nutrient value was evaluated. The nutritional requirement of juvenile Schizothorax Prenanti for protein,fat, minerals and gross energy were studied. And so did the digestibility and enzymolysis rate in vitro of Schizothorax Prenanti to different feed.Experiment One: Evaluation of nutritive value and analysis of the nutritive composition in the muscle of Schizothorax Prenanti.Contents of the common nutritive composition were analyzed by national standard method in the muscle of small juvenile Schizothorax Prenanti ( average weight: 1.9±0.2g) , large juvenile fish (average weight: 72.4±7.3g) and adult fish ( average weight : 501.8± 35.5g ) , and so was the composition of fatty acids , amino acids . The results were as following:(1)In the muscle of Schizothorax Prenanti at three different stages, the common nutritive compositions were no significant difference, the moisture was the highest, among protein, fat and ash, the content descended in rum, and the NFE was the least, the contents of moisture, protein and ash had no remarkable variety, but fat and NFE had.(2)There were 27 kinds fatty acids in the muscle of Schizothorax Prenanti, include 9 kinds SFA and 18 kinds UFA. The composition of fatty acids had three characteristics. First, the content of UFA was higher than that of SFA. Second, the UFA contained more HUFA, the average proportion of HUFA in fatty acids was 19.88%. And third, from small juvenile fish to adult fish the contents of UFA ranged were very little, but the contents of HUFA had evident variety, especially, there were notable difference between large juvenile fish and adult fish (P<0.05).(3)There were 18 kinds amino acids were examined from the muscle of Schizothorax Prenanti. At different stages, the contents of all amino acids in the muscle were steady. The essential amino acids for human being accounted for 47.93% of total amino acids. The content of glutamic acid was considerably high, reaching about 14.56% of total amino acids . The content of delicious amino acids was 29.44g/100g dry matter. The AAS of the muscle was 70 and CS was 41.Experiment Two: Studies on suitable nutrient content in formulated diet for juvenile Schizothorax PrenantiThe nutritional requirement of juvenile Schizothorax Prenanti for protein,fat, minerals and gross energy were studied through 2 expriments.A 50-day growth experiment was conducted to determine the optimum dietary protein level for juveniles of Schizothorax Prenanti, 9 protein levels (24.09%, 27.96%, 31.89%,36.11%, 40.15%, 44.07%, 47.92%, 52.07%, 56.17%) were formulated .The results showed that dietary protein levels influenced significantly the growth rate, feed coefficient, protein efficiency(P<0.05), when protein level ranged from 24.09% to 40.15%, the growth rate ascended linearly. In a definite range(CP<40.15%),the regression equation between growth rate(Y) and dietary protein level(X) was Y=3.0827X-33.362(r=0.9862, P<0.01). Among all the protein levels, the regression equation between growth rate(Y) and dietary protein level(X) was Y=-l63.2+11.825X-0.1427X2(r=0.9207). It was suggested that the optimum dietary protein level for the juveniles of Schizothorax Prenanti should be 35.96%-41.43%.An orthogonal designL9(34) was adopted to determine the nutritional requirement for protein (40.42%),fat (6.02%), minerals(4.0%),and gross energy(13.09 kJ.g-1),respectively, using growth rate, protein efficiency and feed conversion ratio as the biological indexes to assess the feeding effect. The results showed that the influence of nutrients on the growth rate and protein efficiency was as following order: protein> gross energy > fat > minerals, in the range of the factor levels. Thus, protein level had a main effect on growth and body composition of Schizothorax Prenanti (P<0.05) .Experiment Three: Studies on digestibility in vitro and enzymolysis rate of Schizothorax...
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