本试验旨在用套算法和插值法测定与估测肉用绵羊花生秧有效能值，确定替代法中饲粮中适宜花生秧替代比例，为单一秸秆饲料有效能值的测定与估测提供方法学上的参考。选用体重为（45.00±1.96） kg的体况良好的杜泊×小尾寒羊F1肉用成年羯羊54只，采用随机区组设计，分为9组，饲粮分别为基础饲粮、全花生秧饲粮和分别以10%、20%、30%、40%、50%、60%、70%花生秧替代基础饲粮的试验饲粮，每组6个重复，每个重复1只羊。预试期10 d，正试期9 d，其中气体代谢试验3 d，消化代谢试验6 d。结果表明：1）全花生秧饲粮组花生秧干物质（DM）表观消化率与20%、30%、40%组间差异不显著（P>0.05），显著高于其他各组（P<0.05）。全花生秧饲粮组花生秧有机物（OM）表观消化率与20%组差异不显著（P>0.05），但显著高于其他各组（P<0.05）。全花生秧饲粮组花生秧总能（GE）、中性洗涤纤维（NDF）、酸性洗涤纤维（ADF）、粗脂肪（EE）表观消化率显著高于10%组（P<0.05），粗蛋白质（CP）表观消化率显著低于10%组（P<0.05），与其他各组间差异不显著（P>0.05）。2）花生秧消化能（DE）、代谢能（ME）均具有相同的规律，即全花生秧饲粮组DE、ME （8.57、6.69 MJ/kg DM）与20%（8.22、6.58 MJ/kg DM）、30%（8.02、6.50 MJ/kg DM）、40%组（8.10、6.52 MJ/kg DM）差异不显著（P>0.05），但显著高于其他组（P<0.05）。3）插值法求得花生秧ME"真值"为6.62 MJ/kg DM，接近于套算法得到的花生秧ME。综合得出，套算法可以用于肉用绵羊估测花生秧（单一粗饲料）的DE和ME；用套算法测定花生秧秸秆类粗饲料有效能值，其在饲粮中的适宜替代比例为20%~40%。

This study aimed to determine and estimate available energy value of peanut vine for mutton sheep using substitution and extrapolation methods, and find a proper substitution proportion of peanut vine in diet in substitution method, for the purpose of providing a reference for determination and estimation of available energy value of single straw feed. Fifty four healthy adult crossbreed wethers (Dorper×small-tailed Han F1) with body weight of (45.00±1.96) kg were used in a randomized block design. The wethers were divided into nine groups with six replicates per group and 1 sheep per replicate. Sheep in different groups were fed basal diet, full peanut vine diet and experimental diets using different proportions (10%, 20%, 30%, 40%, 50%, 60%, and 70% respectively) of peanut vine to substitute basal diet. The adaptation period lasted for 10 d; the experimental period lasted for 9 d, including 3 d of gas metabolism test and 6 d of digestion and metabolism test. The results showed as follows:1) no significant difference was found in dry matter (DM) apparent digestibility among 20%, 30%, 40% groups and full peanut vine diet group (P>0.05), while these groups were significantly higher than the other groups (P<0.05). Apparent digestibility of organic matter (OM) of full peanut vine diet group had no significant difference with that of 20% group (P>0.05), and was significantly higher than other groups (P<0.05). Apparent digestibility of gross energy (GE), neutral detergent fiber (NDF), acid detergent fiber (ADF) and ether extract (EE) of full peanut vine diet group were significant higher than those of 10% group (P<0.05), while apparent digestibility of crude protein (CP) was significantly lower than that of 10% group (P<0.05), and all of them had no significant differences with the other groups (P>0.05). 2) Digestive energy (DE) and metabolizable energy (ME) of peanut vine showed a similar trend, which was full peanut vine diet group (8.57 and 6.69 MJ/kg DM) had no significant difference with 20% (8.22 and 6.58 MJ/kg DM), 30% (8.02 and 6.50 MJ/kg DM), and 40% groups (8.10 and 6.52 MJ/kg DM), but these groups were significantly higher than the other groups. 3) The 'true' ME of peanut vine calculated by extrapolation method was 6.62 MJ/kg DM, which was close to ME form substitution method. It is concluded that the substitution method can be used for the calculation of DE and ME of peanut vine as a single forage for mutton sheep; the appropriate substitution proportion of peanut vine (straw feed) in diet is 20% to 40% for determination of available energy value.