Sahlu T, Hart S P, Le-Trong T, Jia Z, Dawson L, Gipson T, Teh T H
E (Kika) de la Garza Institute for Goat Research, Langston University, OK 73050, USA.
J Dairy Sci. 1995 Feb;78(2):378-87. doi: 10.3168/jds.S0022-0302(95)76646-2.
Sixty-three multiparous Alpine does were blocked by pregnancy type (single vs. multiple) on d 90 of pregnancy and assigned to one of nine diets to evaluate the interaction of prepartum protein and energy intake on BW change, kidding, and subsequent production and composition of milk. Treatments were factorial with three percentages of CP (8.5, 11.5, and 14.5% of DM) and three concentrations of metabolizable energy (1.80, 2.16, and 2.53 Mcal/kg of DM). Does were fed for ad libitum intake during pregnancy and switched to a lactation diet (16% CP and 2.35 Mcal of metabolizable energy/kg of DM) after parturition. Milk production and composition were recorded for the first 15 wk of lactation. Prepartum BW gain increased quadratically as protein amount increased but was unaffected by energy. Kidding rate, litter weight, and gestation length were unaffected by protein or energy amounts. Milk production in the subsequent lactation increased quadratically in response to prepartum CP (2.59, 3.26, and 3.07 kg/d for 8.5, 11.5, and 14.5% CP, respectively). Milk production increased linearly in response to prepartum metabolizable energy concentration (2.63, 3.05, and 3.26 kg/d for 1.80, 2.16, and 2.53 Mcal/kg of DM, respectively). Milk fat percentage increased linearly in response to increased prepartum energy. Production of milk fat, protein, SNF, FCM, and SCM were affected quadratically by increased prepartum CP and linearly by prepartum energy, following the pattern for milk production. The present recommendations for prepartum CP and energy appear to be adequate for gestation and subsequent lactation performance of dairy goats.
63只经产阿尔卑斯奶山羊在妊娠第90天按妊娠类型（单胎与多胎）进行分组，并分配到9种日粮处理之一，以评估产前蛋白质和能量摄入量对体重变化、产羔以及随后的产奶量和奶成分的交互作用。处理采用析因设计，包含三种粗蛋白水平（分别为干物质的8.5%、11.5%和14.5%）和三种代谢能浓度（分别为1.80、2.16和2.53兆卡/千克干物质）。奶山羊在妊娠期间自由采食，分娩后转换为泌乳期日粮（粗蛋白16%，代谢能2.35兆卡/千克干物质）。记录泌乳期前15周的产奶量和奶成分。产前体重增加随蛋白量增加呈二次曲线上升，但不受能量影响。产羔率、产仔体重和妊娠期不受蛋白或能量水平的影响。随后泌乳期的产奶量随产前粗蛋白水平呈二次曲线增加（粗蛋白水平为8.5%、11.5%和14.5%时，产奶量分别为2.59、3.26和3.07千克/天）。产奶量随产前代谢能浓度呈线性增加（代谢能浓度为1.80、2.16和2.53兆卡/千克干物质时，产奶量分别为2.63、3.05和3.26千克/天）。奶脂肪率随产前能量增加呈线性增加。产前粗蛋白增加使乳脂肪、乳蛋白、非脂固形物、校正乳和标准乳产量呈二次曲线变化，产前能量使其呈线性变化，变化模式与产奶量一致。目前关于产前粗蛋白和能量的建议似乎足以满足奶山羊的妊娠及随后的泌乳性能需求。
