Abstract: We used different alfalfa hay as the research object,including Shanxi (SX),Gansu (GS) and American alfalfa hay (US). Conventional methods and Near-infrared spectroscopy (NIRS) were used to determine nutrients and evaluate their forage value. The results showed that conventional methods and Near-infrared methods showed similar trends in the determination of nutrient indicators. The results of conventional methods showed that US had the highest DM (Dry matter) and SX had the lowest DM. The ash content of SX was the Highest,and US was the lowest. NIRS measurement results showed that there was a significant difference in EE and NDF contents. EE content showed that SX was the highest,US was the lowest,NDF content of SX was the highest,and GS was the lowest. There are certain differences in the nutrient results which measured by the two methods,especially Ash and EE,and the other nutrient content has less differences. The results of the mineral elements show that SX has the highest K and Mg content. The evaluation result of feed value showed that the RFV (Relative feed value) value of SX was the highest,and the milk per ton index of SX was the highest. This study suggests that although the SX evaluation index was the highest,the import of U.S alfalfa hay had a high content of CP,and there was still a big Gap between the domestic alfalfa hay and American alfalfa hay.

Key words: Alfalfa, Hay, Nutrition, Feeding Value

摘要： 本研究以不同苜蓿干草为研究对象，包括山西（SX）、甘肃（GS）和美国（US）进口苜蓿干草，分别用常规法（conventional）和近红外光谱法（NIRS）测定养分并评估其饲用价值。研究发现，常规法和近红外法测定养分指标表现出相似的趋势。常规法测定结果显示，US的干物质（dry matter，DM）最高，SX的DM最低。灰分（Ash）含量最高的为SX，最低为US。NIRS测定结果显示EE和NDF含量具有显著差异性，EE含量显示SX最高，US最低，NDF含量SX最高，GS最低。3种苜蓿矿物元素结果显示，SX的K和Mg含量最高。饲用价值评价结果为，SX的RFV （relative feed value）值最高，其奶吨指数也是最高。研究认为虽然SX苜蓿干草许多评价指数最高，但US苜蓿干草CP含量高，国产苜蓿干草与美国苜蓿干草仍然有一定的差距。

关键词: 苜蓿, 干草, 营养成分, 饲用价值