夏季不同比例燕麦草与天然牧草混合饲喂对藏羊消化代谢的影响  

Proportion of oat grass and natural herbage in summer on the digestive metabolism of Tibetan sheep

作　　者：冉丽娟 李福厚[1] 程云湘 侯扶江[1] RAN Lijuan;LI Fuhou;CHENG Yunxiang;HOU Fujiang(State Key Laboratory of Grassland Agro-ecosystems/Key Laboratory of Grassland Livestock Industry Innovation,Ministry of Agriculture and Rural Affairs/College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou 730020,Gansu,China;School of Ecology and Environment,Inner Mongolia University,Hohhot 010021,Inner Mongolia,China)

机构地区：[1]兰州大学草地农业生态系统国家重点实验室/兰州大学农业农村部草牧业创新重点实验室/兰州大学草地农业科技学院,甘肃兰州730020 [2]内蒙古大学生态与环境学院,内蒙古呼和浩特010021

出　　处：《草业科学》2020年第11期2334-2342,共9页Pratacultural Science

基　　金：教育部创新团队发展计划(IRT_17R50);甘肃省2019年草原生态治理修复科技支撑和甘肃省现代草食畜产业技术体系(GARS-08)。

摘　　要：本研究以4种比例的燕麦(Avena sativa)草与高寒草甸天然牧草混合日粮,探讨了夏季不同比例的燕麦草与天然牧草混合饲喂对放牧藏羊消化代谢的影响。结果表明,放牧藏羊的干物质(dry matter,DM)、有机物质(organic matter,OM)、粗蛋白(crude protein,CP)、粗脂肪(ether extract,EE)、中性洗涤纤维(neutral detergent fiber,NDF)、酸性洗涤纤维(acid detergent fiber,ADF)采食量和消化率随着日粮中燕麦草比例的增加而总体呈降低趋势。燕麦草比例超过50%极显著降低了藏羊的DM、OM采食量和消化率(P<0.01)。粪氮含量随着氮采食量的增加呈"马鞍形"变化,日氮采食量为4.65 g时,日粪氮含量最低,为1.13 g;氮消化率随着氮采食量的增加呈"驼峰形"变化,日氮采食量为5.60g时,氮消化率最高,为75.53%。总能采食量随着日粮中燕麦草比例的增加而下降。综上,夏季全天然牧草可以满足藏羊的生长代谢,且不宜对其饲喂燕麦草。In this study,four mixed diets with different proportions of oat grass and alpine meadow natural herbage were used to carry out a simulated grazing experiment.The effects of summer cultivated different proportions of oat grass were mixed with natural herbage feeding on the digestion and metabolism of grazing Tibetan sheep were subsequently studied.Our results showed that the intake and digestibility of dry matter(DM),organic matter(OM),crude protein(CP),ether extract(EE),neutral detergent fiber(NDF)and acid detergent fiber(ADF)decreased with increasing oat grass proportions.A greater than 50%of oat grass significantly reduced the DM and OM intake and digestibility in Tibetan sheep(P<0.01).The fecal nitrogen content presented a concave parabola change with increasing nitrogen intake.When the daily nitrogen intake was 4.65 g,the daily fecal nitrogen content was the lowest,at 1.13 g.As nitrogen intake increased,the digestibility of nitrogen presented a convex parabola.The digestibility of nitrogen was the highest,at 76.53%,when the daily nitrogen intake was 5.60 g.Total energy intake decreased with the increase of oat grass ratio.In conclusion,in summer,all natural herbage can meet the growth and metabolism of Tibetan sheep,and it is not suitable to feed additional oat grass.

关 键 词：干物质采食量 总能采食量 氮采食量 尿氮 粪能 高寒草甸 

分 类 号：S826.5[农业科学—畜牧学]