育肥中后期杜泊羊湖羊杂交F1代公羊能量需要量参数

【目的】为杜湖杂交F1代公羊确定育肥中后期的能量需要量参数，为该品种绵羊能量这一营养指标提供理论依据。【方法】本试验采用比较屠宰法，将能量需要量解析为维持能量需要量和生长能量需要量，采用代谢能和净能两个指标体系进行测定。试验选用体重为35 kg左右的杜湖杂交F1代公羊42只，其中的30只试验羊用于比较屠宰试验，将试验羊随机分为自由采食组、低限饲组和高限饲组3个采食量水平，使其日增重分别达到350、150和0 g，分别在试验第1天（6只）、自由采食组羊体重分别达到43 kg（6只）和50 kg（18只）时分3批进行屠宰，以便得到试验羊的体能量沉积量。另外，12只羊用于消化代谢试验，同样按上述采食量水平随机分为3组，利用推荐公式对试验羊的甲烷产量和产热量进行预测，并以此计算得到代谢能摄入量分别10.69、11.99和12.33 MJ（每采食1 kg日粮的代谢能摄入量）。【结果】维持净能（net energy for maintenance，NEm）需要量为271.6 kJ•kg-0.75, 代谢能维持效率为0.66；维持代谢能（metabolizable energy for maintenance，MEm）需要量为413.7 kJ•kg-0.75；35-50 kg日增重100-350 g的生长净能需要量为0.81-3.12 MJ•d-1；35-50 kg日增重100-400 g的生长代谢能需要量为1.47-5.38 MJ•d-1，代谢能生长效率为0.55。【结论】较为系统地得到了35-50 kg杜湖杂交F1代公羊能量需要量指标，其中包括维持净能、维持代谢能、生长净能和生长代谢能，与国内外肉羊营养需要量的研究结果相近。

Energy Requirement of Hu Sheep and Dorper Sheep Hybrid F1 Rams

【Objective】 This research aimed to define the energy requirement parameters for Hu sheep and Dorper sheep hybrid F1 male rams in the late fattening period, to provide a theoretical basis of scientific supply of energy for this breed of sheep. 【Method】The experiment adopted comparative slaughter method, divided the general requirement into requirement for maintenance and requirement for growth. Adapted metabolizable energy requirement and net energy requirement of these two index systems were used to measure the energy requirements. A total of 42 Hu sheep and Dorper sheep hybrid rams at body weight close to 35 kg were selected, and 30 of them were used in the slaughter experiments. They were randomly divided into 3 intake level groups which were ad libitum group, low-restriction group and high-restriction group, to make their average daily gain reach to 350, 150 and 0g. All rams were slaughtered on 1st day (6n), 20th day (6n) and 42th (18n) day in order to get the retained energy value. Remained 12 rams were used in the digestibility experiment, the rams were divided into 3 intake level groups as comparative slaughter experiment, the recommended formulation was used to predict the methane production and heat production, and then following the above-mentioned results the calculated metabolizable energy intakes of 3 intake levels were 10.69, 11.99 and 12.33 MJ•kg-1 (metabolizable energy intake per kg ration).【Result】The experiment results suggested that the daily net energy requirement for maintenance (NEm) was 271.6 kJ•kg-0.75,the partial efficiency of use of ME for NE for maintenance was 0.66.The daily metabolizable energy requirement for maintenance (MEm) was 413.7 kJ•kg-0.75. Net energy requirements for growth ranged from 0.81-3.12 MJ•d-1 at 35 to 50 kg daily gain 0-400 g. Metabolizable energy requirements for growth ranged from 1.47-5.38 MJ•d-1 at 35 to 50 kg daily gain 0-350 g. The partial efficiency of use of ME for NE for growth was 0.55. 【Conclusion】This research systematicly defined the energy requirement parameters for 35-50 kg Hu sheep and Dorper sheep hybrid F1 male rams in the late fattening period, including net energy for maintenance, metabolizable energy for maintenance, net energy for growth and metabolizable energy for growth, and the results is closely to the domestic and foreign research on energy requirement.