The aim of this study was to determine the energy and protein requirements for maintenance of Dor-per and Hu hybrid F1 ewes during pregnancy and to provide data for formulating diet for the mutton sheep. The experiment consisted of feeding experiment, digestion metabolism experiment and respirometary experiment. Fifteen sheep with body weight of (43.34±1.37) kg at the age of nine months were used. After the treatments of synchronization of estrus and free mating, the sheep were assigned randomly into three groups with five e-wes in each group, which were ad libitum ( Ad) group, 70% Ad group and 50% Ad group. Feces and urine were collected using total feces collection method on 40, 100 and 130 days of pregnancy;meanwhile, respiro-metary experiment was conducted, and metabolic parameters of nitrogen and energy at different periods of pregnancy were calculated;finally the requirements of net nitrogen, net energy and metabolic energy for main-tenance of the cross combination during pregnancy were calculated by establishing the allometric regressions re-spectively between nitrogen intake and nitrogen retention, the logarithm of heat production and metabolizable energy intake according to the results of digestion metabolism experiment and respirometary experiment. The re-sults showed as follows:1) the apparent digestibility of nitrogen on 40, 100 and 130 days of pregnancy were 56.16% to 62.24%, 60.43% to 65.47% and 58.79% to 62.01%, respectively. 2) The apparent digestibility of gross energy on 40, 100 and 130 days of pregnancy were 51. 18% to 64. 25%, 60. 86% to 66. 17%, and 63.20%~67.36%, respectively. 3) Requirements of net nitrogen, net energy and metabolic energy for mainte-nance of this breed on 40, 100 and 130 days of pregnancy were 287.9, 301.3 and 430.7 mg/(kg W0.75·d), 194.01, 244.59 and 256.08 kJ/(kg W0.75·d), and 283.18, 412.26 and 468.56 kJ/(kg W0.75·d), respec-tively. The research defines the energy and protein requirement parameters for Dorper sheep and Hu sheep hy-brid F1 ewes during pregnancy, including net energy, metabolizable energy and net nitrogen for maintenance.%本研究旨在确定杜泊羊×湖羊(杜湖)杂交F1代母羊妊娠期能量和蛋白质维持需要量，为该杂交组合肉羊饲粮配制提供较为合理的能量和蛋白质需要标准。分为饲养试验、消化代谢试验和呼吸测热试验。选取15只月龄(9月龄)、体重[(43.34±1.37) kg]相近的母羊，经同期发情、自由交配后随机分为自由采食组、70%自由采食量、50%自由采食量组，每组5只母羊。在妊娠期40、100、130 d分别采用全收粪法收集粪尿，同时进行呼吸测热试验，计算得到母羊在不同妊娠时期氮、能量的表观代谢参数，依据消化代谢试验和呼吸测热试验结果分别利用沉积氮和食入氮、产热量的对数和代谢能采食量建立异速回归方程，最终得到该杂交组合在妊娠期40、100、130 d时维持净氮、维持净能、维持代谢能需要量。结果表明：1)氮表观消化率在妊娠40、100、130 d时分别为56.16%~62.24%、60.43%~65.47%、58.79%~62.01%。2)总能表观消化率在妊娠40、100、130 d时分别为51.18%~64.25%、60.86%~66.17%、63.20%~67.36%。3)在母羊妊娠40、100、130 d时维持净氮分别为287.9、301.3、430.7 mg/(kg W0.75·d)；维持净能分别为194.01、244.59、256.08 kJ/( kg W0.75· d )；维持代谢能分别为283.18、412.26、468.56 kJ/(kg W0.75·d)。本研究最终得到了杜湖杂交F1代母羊妊娠期能量、蛋白质需要量指标，包括维持净能、维持代谢能、维持净氮。
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