本试验旨在研究饲粮能量水平对育成期崂山奶山羊能量利用率的影响。选择体重为(18.43±0.76) kg的崂山奶山羊育成母羊30只,采用单因素随机分组设计分成3组,每组10个重复,每重复1只羊。分别饲喂粗蛋白质、钙及磷水平基本一致,消化能水平分别为10.40、11.47及12.51 MJ/kg的3种全混合日粮。预试期10 d,正试期90 d。结果表明:1)试验后期3组试羊随着饲粮能量水平的提高,总能消化率依次提高,12.51 MJ/kg组试羊的总能消化率、总能代谢率及消化能代谢率显著高于10.40 MJ/kg组(P<0.05);3组试羊的总能、粪能及尿能间呈显著差异(P<0.05),10.40 MJ/kg组< 11.47 MJ/kg组< 12.51 MJ/kg组;10.40 MJ/kg组试羊的甲烷能显著低于11.47及12.51 MJ/kg组(P<0.05)。2)10.40 MJ/kg组试羊末重及平均日增重显著低于11.47及12.51 MJ/kg组(P<0.05),但11.47 MJ/kg组与12.51 MJ/kg组间无显著差异(P>0.05)。3)育成期崂山奶山羊消化能和代谢能需要量与代谢体重和平均日增重关系的回归公式:DE=0.675W^0.75+0.110ADG(P=0.006,R²=0.982);ME=0.526W^0.75+0.076ADG(P=0.027,R²=0.873)[式中DE为消化能(MJ/d),ME为代谢能(MJ/d),W^0.75为代谢体重(kg),ADG为平均日增重(g)]。综合得出,育成期崂山奶山羊母羊饲粮中消化能以11.47~12.51 MJ/kg(干物质基础)较为适宜。

This experiment was conducted to investigate the effects of dietary energy level on energy utilization of Laoshan dairy goat at fattening period. Thirty female Laoshan dairy goats with an average weight of (18.43±0.76) kg were used in a single-factor randomized design and divided into 3 groups with 10 replicates in each group and 1 goat per replicate. Goats in three groups were fed diets with consistent crude protein, calcium and phosphorus levels, but with different digestive energy levels (10.40, 11.47 and 12.51 MJ/kg, respectively). The pretrial lasted for 10 d, and the trial lasted for 90 d. The results showed as follows: 1) with the increase of dietary energy level, gross energy increased, and gross energy digestibility, gross energy metabolic rate and digestive energy metabolic rate in 12.51 MJ/kg group were significantly higher than that in 10.40 MJ/kg group (P<0.05); there were significant differences among 3 groups in gross energy, fecal energy and urinary energy (P<0.05), and 10.40 MJ/kg group<11.47 MJ/kg group<12.51 MJ/kg group; methane energy in 10.40 MJ/kg group was significantly lower than that in 11.47 and 12.51 MJ/kg groups (P<0.05). 2) Final weight and average daily gain of goats in 10.40 MJ/kg group was significantly lower than those in 11.47 and 12.51 MJ/kg groups (P<0.05), and there were no significant differences between 11.47 MJ/kg group and 12.51MJ/kg group (P>0.05). 3) The regression formulas between digestible energy or metabolizable energy requirements and average daily gain of Laoshan dairy goats at fattening period were as follow: DE=0.675W^0.75+0.110ADG (P=0.006, R²=0.982); ME=0.526W^0.75+0.076ADG (P=0.027,R²=0.873) [DE was digestive energy (MJ/d), ME was metabolizable energy (MJ/d), W^0.75 was metabolic weight (kg), and ADG was average daily gain (g)]. In conclusion, the optimal dietary digestive energy level for female Laoshan dairy goats at fattening period is 11.47 to 12.51 MJ/kg (dry matter basis).