沙生植物资源量大、 生长快、 占地面积广, 是改善环境和治理荒漠化的主要植物, 但其饲用价值没有得到充分利用。 目前由于畜牧业的规模化、 集约化发展, 出现牧草匮乏, 商品牧草供应量严重不足, 导致畜草矛盾日益增加。 沙生植物平茬收获, 充分挖掘沙生植物的潜在饲用价值, 开发、 生产非常规饲料, 对推动我国荒漠、 半荒漠地区的畜牧业发展和生态修复至关重要。 选择内蒙古阿拉善左旗珍珠猪毛菜(简称珍珠)、 红砂、 油蒿、 骆驼刺、 柠条锦鸡儿(简称柠条) 和沙米六种常见沙生植物为研究对象, 利用光谱学方法测定样品中粗蛋白(CP)、 粗脂肪(EE)、 粗纤维(CF)、 钾(K)、 钠(Na)和钙(Ca)等14种营养成分和亮氨酸(Leu)、 赖氨酸(Lys)、 蛋氨酸(Met)、 胱氨酸(Cys)、 苏氨酸(Thr)等17种氨基酸含量, 并与四种常规饲料(优质玉米、 NT-2级稻谷、 GB-2级大豆和GB-3级苜蓿草粉)进行比较, 获得沙生植物营养价值和潜在饲用价值的评价结果。 结果表明:(1)六种沙生植物的CP含量、 EE含量和矿物元素含量均处于较高水平, CF含量高于泌乳母牛日粮中CF占日粮干物质的13%, 等同于或优于以上四种常规饲料。(2)该研究中氨基酸含量和氨基酸化学评分(CS)的结果为: 六种沙生植物都含有17种氨基酸, 且组成较为均衡。 其中油蒿、 骆驼刺、 柠条和沙米中的必需氨基酸含量及营养价值均高于优质玉米和NT-2级稻谷。 Leu和Lys分别是3种沙生植物红砂、 骆驼刺、 柠条和珍珠、 优质玉米、 NT-2级稻谷的第一限制氨基酸, 而Thr和Met+Cys分别是油蒿和沙米、 GB-2级大豆、 GB-3级苜蓿草粉的第一限制氨基酸。(3)主成分分析结果表明, 珍珠、 柠条和沙米的营养价值高于常规饲料GB-3级苜蓿草粉, 且六种沙生植物的营养价值均高于优质玉米和NY-2级稻谷。 综上表明, 研究区常见的六种沙生植物不仅具有生长快、 地上生物量大和耐刈割等特点, 更具有较大的饲用开发潜力, 是荒漠、 半荒漠地区良好的饲料来源, 研究结果为指导饲料氨基酸的平衡和合成氨基酸提供可信的实验依据和理论依据。

Psammophytes are the main plants for improving the environmental quality and controlling desertification because of its large resource quantity, rapid growth and wide planting area, but their feeding value has not been fully utilized. At present, due to large-scale and intensive development of animal husbandry, there is a lack of pasture, and the supply of commercial pasture is seriously insufficient, resulting in an ever-increasing contradiction between livestock and pasture. Because of the stubble harvest of the psammophytes, it is crucially important to fully explore its potential feeding value, develop and produce the unconventional feeds and promote the development of animal husbandry and ecological restoration in desert and semi-desert areas of China. In this study, 14 kinds of nutrients (such as crude protein (CP), ether extract (EE), crude fiber (CF), K, Na and Ca, et al.) and 17 kinds of amino acids (such as leucine (Leu), lysine (Lys), methionine (Met), cystine (Cys) and threonine (Thr), et al.) in 6 kinds of common psammophytes ( Salsola passerina, Reaumuria songarica, Artemisia ordosica, Alhagi sparsifolia, Caragana korshinskii and Agriophyllum squarrosum), which were collected from Alxa Left Banner, Inner Mongolia, were analyzed by using the spectroscopy technology. Compared with 4 kinds of conventional feeds (high-quality corn grain, NT-2 paddy, GB-2 soybean and GB-3 alfalfa meal), the contents of nutrients and amino acids and evaluation of the nutritional and potential feed values of 6 kinds of psammophytes were obtained. The results showed that: (1) The CP, EE and mineral element contents of the 6 kinds of psammophytes were all at a relatively higher level, and the CF contents in psammophytes were higher than 13% of dry matter in the diet of lactating cows, equivalent to or better than the above 4 kinds of conventional feeds. (2) 6 kinds of psammophytes in this study, contained 17 kinds of amino acids, and the composition was more balanced based on the results of amino acid chemical score (CS) . The essential amino acid contents and nutritional values of Artemisia ordosica, Alhagi sparsifolia, Caragana korshinskii and Agriophyllum squarrosum were higher than those of high-quality corn grain and NT-2 paddy. Leu and Lys were the first limiting amino acids of the Reaumuria songarica, Alhagi sparsifolia, Caragana korshinskii and Salsola passerina, high-quality corn grain, NT-2 paddy, respectively, while Thr and Met+Cys were the first limiting amino acids of Artemisia ordosica and Agriophyllum squarrosum, GB-2 soybean, GB-3 alfalfa meal, respectively. The results of this study will provide a reliable experimental and theoretical basis for guiding the balance of amino acids in feed and synthesizing amino acids. (3) The results of principal component analysis showed that the nutritional values of Salsola passerina, Caragana korshinskii and Agriophyllum squarrosum were higher than that in conventional feed (GB-3 alfalfa meal), and the nutritional values of the 6 kinds of psammophytes were higher than that of high-quality corn grain and NY-2 paddy. In conclusion, the 6 kinds of psammophytes in this study not only had the characteristics of rapid growth, large above-ground biomass and resistance to mow, but also greater developing potential for forage, which can serve as a good source of feed for desert and semi-desert areas. The results provided a reliable experimental data and theoretical basis for the guidance of amino acid balance and amino acid synthesis.