高山美利奴育成公羊在返青期与盛草期牧场的营养监测  

Evaluating grazing nutrition of alpine merino growing rams in the regreening and grassy stages of pasture herbage

作　　者：赵志伟 张宏伟 王虎成[1] 孙晓萍[2] 李发弟[1] 杨博辉[2] ZHAO Zhiwei;ZHANG Hongwei;WANG Hucheng;SUN Xiaoping;LI Fadi;YANG Bohui(State Key Laboratory of Grassland Agro-ecosystems,Lanzhou University/Engineering Research Center of Grassland Industry,Ministry of Education,Lanzhou University,Key Laboratory of Grassland Livestock Industry Innovation,Ministry of Agriculture and Rural Affairs,Lanzhou University/College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou 730020,Gansu,China;Lanzhou Institute of Animal Science&Veterinary Pharmaceutics,Chinese Academy of Agricultural Sciences,Lanzhou 730050,Gansu,China)

机构地区：[1]兰州大学草地农业生态系统国家重点试验室/兰州大学农业农村部草牧业创新重点试验室/兰州大学草地农业科技学院反刍动物研究所,甘肃兰州730020 [2]中国农业科学院兰州畜牧与兽药研究所,甘肃兰州730050

出　　处：《草业科学》2022年第1期171-179,共9页Pratacultural Science

基　　金：中国农业科学院重大产出科研选题“高山美利奴羊新品种培育与产业化(CAAS-ZDXT2018006)”;甘肃省重点研发计划(20YF3NA006)。

摘　　要：本研究以祁连山放牧地的高山美利奴育成公羊为研究对象,于返青期和盛草期,采用粪袋全收粪和酸不溶灰分(AIA)结合法测定其采食量,并探究其放牧地牧草营养物质的供给规律和其营养的盈缺。结果显示,盛草期放牧草地植物群落优势度指数、地上生物量、多样性指数、物种丰富度指数、均匀度指数均显著高于返青期(P<0.05)。在牧草养分化学指标上,粗蛋白和粗灰分含量在盛草期显著高于返青期(P<0.05),盛草期牧草粗饲料分级指数(GI)也显著高于返青期(P<0.05)。返青期和盛草期高山美利奴育成公羊干物质、粗蛋白采食量差异不显著(P>0.05),代谢能采食量在盛草期显著高于返青期(P<0.05)。牧草有机物和干物质消化率返青期和盛草期差异不显著(P>0.05),牧草粗蛋白、中性洗涤纤维和酸性洗涤纤维消化率在返青期显著高于盛草期(P<0.05)。盛草期高山美利奴育成公羊瘤胃氨态氮(NH3-N)含量、丁酸、支链脂肪酸比例显著高于返青期(P<0.05),高山美利奴育成公羊瘤胃内总挥发性脂肪酸含量返青期显著高于盛草期(P<0.05)。参照中国美利奴育成公羊(体重70 kg,日增重100 g)营养需要推荐量,高山美利奴育成公羊每只日代谢能和粗蛋白采食量在返青期分别比推荐量低9.32 MJ和45.23 g·d^(−1);而在盛草期二者则分别低7.32 MJ和32.64 g·d^(−1)。综上所述,盛草期牧草GI值、牧草生产力显著高于返青期;体重为70 kg的高山美利奴育成公羊在返青期和盛草期牧场,日增重达到100 g时,代谢能和粗蛋白摄入量均不足,需补饲一定量的能量和蛋白饲料。Alpine Merino growing rams grazing in the Qilian Mountains,the research object in this study,were used to measure forage intake,nutrient digestibility,and rumen parameters in herbage regreening and grassy stages to determine the forage nutrition supply law and the nutritional status of the rams during these stages.The dominance index of plant communities in the grazing grassland and the diversity index,richness index,evenness index,and aboveground biomass of pasture in the grassy stage were higher than those in the regreening stage(P<0.05).Additionally,the grading index(GI),crude protein,and crude ash were higher in the grassy stage than in the regreening stage(P<0.05).There was no difference in the dry matter and crude protein intake of Alpine Merino growing rams,but the metabolic energy intake was higher in the herbage grassy stage than in the regreening stage(P<0.05).In terms of digestibility in the two stages,there was no significant differences between the dry and organic matter(P>0.05),but the crude protein,neutral detergent fiber,and acid detergent fiber were higher in the regreening stage(P<0.05).The total volatile acid content was higher in the regreening stage than in the grassy stage(P<0.05),but the isobutyric acid,butyric acid,isovaleric acid,and ammonia nitrogen content were higher in the grassy stage than in the regreening stage(P<0.05).In the regreening stage,the metabolizable energy intake and crude protein intake of the Alpine Merino growing rams were 9.32 MJ and 45.23 g·d^(−1)per sheep lower than the nutritional requirements,respectively,according to the feeding standard of Chinese Merino sheep(body weight 70 kg,daily gain 100 g).In the grassy stage,the metabolizable energy intake and crude protein intake were 7.32 MJ and 32.64 g·d^(−1)per sheep lower than the nutritional requirements,respectively.In conclusion,the GI value and productivity of pasture in the grassy stage were higher than those in the regreening stage.Furthermore,when the daily gain reached 100 g in 70 kg Alpine Merino shee

关 键 词：冬季牧场 夏季牧场 牧草生产力 细毛羊 生产性能 营养盈缺 营养价值评定 

分 类 号：S826.5[农业科学—畜牧学]