草鱼、团头鲂对伊乐藻的消化与利用

DIGESTION AND UTILIZATION OF ELODEA NVTTALLIl BY CTENOPHARYNYODON IDELLA AND MEGAWBRAMA AMBLYCEPHALA

本文分析了伊乐藻的生化成分和能值,测定了草鱼、团头鲂对伊乐藻生化成分的消化率,草鱼对伊乐藻的最大摄食量、蛋白质利用率和饲料系数。结果表明,伊乐藻含水率为89.8％,干物质中粗蛋白质、粗脂肪、粗纤维素和无氮浸出物含量分别为23.52％、2.88％、26.71％和29.27％,含有17种常见氨基酸,总量为198.04mg/g(干重)。在平均水温20.4℃的室外条件下,草鱼,团头鲂对伊乐藻的干物质消化率分别为56.02％、54.97％,对粗蛋白质消化率分别为79.05％、74.96％,对氨基酸总量的消化率均为77.00％,对粗脂肪消化率分别为73.96％,64.63％,对碳水化合物消化率分别为58.46％、51.36％。在伊乐藻饲养试验中,草鱼每天最大摄食量(Y)与试验鱼体重(X)相关显著,相关系数为0.9154,关系式为Y=3.9449X^(0.8357)。在网箱中饲养草鱼,伊乐藻的粗蛋白质利用率为17.1％,饲料系数为48.2。在小型围栏中饲养草鱼,伊乐藻的粗蛋白质利用率为13.1％,饲料系数为63.4。

Chemical composition and energy content of Elodea Nuttallii were determined by common methods of biochemical analysis. The digestibility, maximum consumption, protein efficiency ratio and food conversion coefficient of N. elodea by grass carp and Chinese bream were studied. In N. Elodea, water content amounted to 89. 8%, protein, fat, cellulose and non-nitrogen contents in dry matter were in proper orders: 23. 52%, 2. 88% , 26. 71%, 29. 27%. Its protein contained 17 common amino acids, including 9 essential amino acid for fish. The content of amino alids was 198. 04 mg/g(dry). Under mean water temperature 20. 4℃ , digestibilities of dry matter,protoin , fat, carbohydrates and amino acids in grass carp fed N. Elodea were in proper order: 56. 02% , 73. 9% , 58.46%, 77.00%, these in chinese bream fed N. Eoldea were in proper ordes: 54. 97%, 72.96%, 64.63%, 51.36%, 77.00%. The maximum consumption (Y, g/24hr) of grass carp fed N. Elodea was related to the body weight of fish (X, g) by equation Y=3. 9449X0.8357 (r= 0. 9154) . In cage, protein efficiency and food conversion coefficient of N. Elodea by grass carp were in proper order: 17. 1% , 48. 2. In endosure, these of N. Elodea by grass carp were in proper orders: 13.1% and 63. 4%.