暖季补饲对高寒牧区天然草地放牧泌乳牦牛产乳性能的效应  

Effects of warm season supplementary feeding on the milk performance of lactating yaks grazing on natural grassland in an alpine pastoral area

作　　者：伪玛张 次仁曲宗[1,2,3] 汪诗平 杨智永[2,3] 张渊 南吉 谢正新 措色 杨颖 张国太 斯确多吉 Weimazhang;Cirenquzong;WANG Shiping;YANG Zhiyong;ZHANG Yuan;Nanji;XIE Zhengxin;Cuose;YANG Ying;ZHANG Guotai;DORJI tsechoe(School of Ecology and Environment,Tibet University,Lhasa 850000,Tibet,China;State Key Laboratory of Tibetan Plateau Earth System,Resources and Environment(TPESRE),Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100101,China;Naqu Alpine Grassland Ecosystem Field National Scientific Observation and Research Station,Nagqu Institute of Qinghai Tibet Plateau,Tibetan University and Chinese Academy of Sciences,Nagqu 852000,Tibet,China;University of the Chinese Academy of Sciences,College of Resources and Environment,Beijing 100049,China;Chinese Academy of Sciences,Qinghai-Tibet Plateau Earth Science Center,Beijing,100101,China)

机构地区：[1]西藏大学生态环境学院,西藏拉萨850000 [2]中国科学院青藏高原研究所青藏高原地球系统与资源环境全国重点实验室,北京100101 [3]西藏那曲高寒草地生态系统国家野外科学观测研究站,西藏那曲852000 [4]中国科学院大学资源与环境学院,北京100049 [5]中国科学院青藏高原地球科学卓越中心,北京100101

出　　处：《草业科学》2024年第1期195-206,共12页Pratacultural Science

基　　金：中国科学院战略性先导科技专项子课题及西藏中央引导地方资金配套项目(XDA26050501);西藏高寒区生态草牧业科技示范项目(XZ202301YD0012C);那曲市色尼区那曲嘎尔德母牦牛牛奶和毛绒体质增效关键技术体系研发项目(E2Pf011001)。

摘　　要：青藏高原高寒草甸草地牧草营养品质虽高,但产量极低,尤其缺乏蛋白饲草且草地呈现不同程度退化,导致泌乳牦牛(Bos grunniens)营养不良,乳产量和品质呈下降趋势。另外,多汁饲料因富含维生素、水分等,通常作为提高奶牛产乳性能的重要饲料种类,但其对泌乳牦牛产乳性能的影响尚不明确。由于青藏高原牧区大多相对干旱,天然草地植物水分含量相对较少,因此预测补给多汁饲料,可能也会提高泌乳期牦牛维生素以及水分的摄取,提高泌乳性能。本研究于2021年暖季(7月-10月)在西藏那曲高寒牧区筛选了体重、年龄、胎次相近的带犊泌乳牦牛24头,随机分4组,在天然草地传统放牧基础上分别设蛋白质饲料[苜蓿(Medicago sativa):1 kg·(d·head)^(-1)]、多汁饲料[萝卜(Raphanus sativus):1 kg·(d·head)^(-1)]、蛋白质加多汁饲料[萝卜和苜蓿各0.5 kg·(d·head)^(-1)]补给和不补给饲料(对照)处理,探讨暖季补给蛋白质和多汁饲料对青藏高原高寒牧区天然草地放牧泌乳期牦牛乳产量和品质(乳脂率、蛋白质率、非脂乳固体率、乳糖率、灰分率、密度、冰点)的影响。结果表明:与对照比较,蛋白质饲料补给显著提高了天然草地放牧泌乳牦牛日产乳量(P<0.05),提高率达22%,延缓了泌乳期牦牛产乳量随时间下降的趋势;多汁饲料补给显著降低了天然草地放牧泌乳牦牛日产乳量,降低率为6%(P<0.05)。与对照比较,单独补给蛋白质饲料或蛋白质加多汁饲料均显著提高了天然草地放牧泌乳牦牛的乳蛋白质率、非脂肪固体率、乳糖率、乳灰分以及乳密度,显著降低了乳冰点,同时补给蛋白质加多汁饲料显著降低了乳脂率。另外,与对照比较,仅补给多汁饲料显著提高了乳脂率、蛋白质率、非脂肪固体率和灰分率,显著降低了乳冰点。但3种补饲处理对泌乳牦牛和犊牛体重均无显著影响(P>0.05)。综上,即使在牧草生长旺The alpine meadow grassland of the Qinghai-Tibet Plateau is known for its high nutritional quality,but its yield is extremely low.The lack of protein forage and grasslands show varying degrees of degradation,which have led to malnutrition among lactating yaks,resulting in a decline in both milk yield and quality.While succulent feed has been known to boost milk production in dairy cows due to its vitamin and water content,its effect on lactating yaks is unclear.Given that most pastoral areas in the region are arid with low water content in natural grasses,supplementing succulent feed may increase vitamin and water intake and improve lactation performance.To investigate this hypothesis,24 lactating yaks with similar weight,age,and parity were selected from the Nagqu alpine pastoral area of Tibet during the 2021(July–October)warm season and were randomly divided into four groups.The groups were fed protein[Medicago sativa:1 kg·(d·head)^(-1)],succulent[Raphanus sativus:1 kg·(d·head)^(-1)],protein+succulents[0.5 kg·(d·head)-1 each of alfalfa and radish],and nonsupplemented feed(control group)in addition to their traditional grazing in natural grassland.The study aimed to determine the effects of protein and succulent feed supplementation on the yield and quality of yak milk during lactation while grazing in the alpine pastoral area of the Qinghai-Tibet Plateau.Results showed that compared to the control,protein feed supplementation led to a significant 22%increase in daily milk yield and delayed the decline of milk production during lactation.In contrast,succulent feed supplementation reduced the daily milk yield by 6%.Protein feed alone or combined with succulent feed significantly increased milk protein percentage,non-fat solids percentage,lactose percentage,ash percentage,and density while reducing the milk freezing point.Additionally,only succulent feed significantly improved milk fat percentage,protein percentage,non-fat solids percentage,ash percentage,and reducing freezing point.However,the three suppl

关 键 词：青藏高原 牦牛 传统放牧 蛋白饲料 多汁饲料 产乳量 乳品质 

分 类 号：S823[农业科学—畜牧学]