Abstract: Forage scarcity constitutes a critical bottleneck for livestock husbandry development in the northern Tibet， where establishing high-quality， productive artificial grasslands is recognized as a pivotal solution. This study systematically evaluated six high-yield forages previously screened for artificical grasslands establishment in Nagqu （Avena sativa， Triticum secale， Brassica rapa， Brassica napus， Elymus sibiricus and Elymus nutans）， using near-infrared reflectance spectroscopy （NIRS） to assess the nutritional parameters of dry forages and comprehensively evaluating the forage quality of them through grading index （GI）. Results demonstrated that four annual forages exhibited crude protein （CP） content of 10.45% to 17.99%， neutral detergent fiber （NDF） content ranged from 34.03% to 65.76%， acid detergent fiber （ADF） content ranged from 27.23% to 41.52%， and GI values ranged from 10.63 to 86.85. Meanwhile， CP had a strong positive correlation with GI， while fiber （e.g.， NDF and ADF） content had a negative correlation with GI. All six species met or exceeded fourth grade forage standards （GI >6.28 MJ）， with B. rapa achieving premium-grade classification （GI >53.68 MJ）. Superior performance in total energy content， mineral content， and palatability positions B. rapa as the optimal candidate for regional promotion in the northern Tibet.

Key words: Nagqu region, Nutritional value, Forage quality, Near-infrared reflectance spectroscopy technology, Grading index

摘要： 饲草短缺是藏北地区畜牧业发展的瓶颈，而建植优质高产的人工草地被认为是攻克这一难关的有效途径。为了进一步评估筛选的适宜那曲地区建植人工草地的6种高产饲草的品质，即燕麦（Avena sativa）、绿麦草（Triticum secale）、芜菁（Brassica rapa）、饲用油菜（Brassica napus）、老芒麦（Elymus sibiricus）和垂穗披碱草（Elymus nutans），本文利用近红外光谱技术测定干饲草的营养指标，并通过分级指数（Grading index， GI）综合评估6种饲草的饲用品质。结果显示，4种一年生饲草的粗蛋白含量为10.45%~17.99%，中性洗涤纤维含量为34.03%~65.76%，酸性洗涤纤维含量为27.23%~41.52%，GI值为10.63~86.85；粗蛋白含量与GI值呈正相关，而纤维含量与GI值呈负相关。此外，6种饲草的品质均可达到4级及以上饲草标准（GI>6.28 MJ），其中芜菁的品质可达到特级饲草标准（GI>53.68 MJ），且其在能源物质总量、矿物质含量和适口性方面表现均最优异，建议在藏北地区推广种植。

关键词: 那曲地区, 营养价值, 饲用品质, 近红外光谱技术, 分级指数