应用粪氮指数法检测青藏高原草甸区成年母牦牛青草期放牧采食量  

Daily Grass Organic Matter Intakes of Female Yak in Green Grass Season in Subalpine Meadow by Fecal Index Method

作　　者：吴伟生[1] 郑群英[1] 刘刚[1] 罗晓林[1] 杨平贵[1] 陈琳[1] 

机构地区：[1]四川省草原科学研究院,四川成都611743

出　　处：《家畜生态学报》2015年第7期33-38,共6页Journal of Domestic Animal Ecology

基　　金：国家公益性行业(农业)科研专项(201003019);国家肉牛牦牛产业技术体系(CARS-38);四川省"十二五"畜禽育种攻关项目(2011NZ0099-5)

摘　　要：试验旨在研究牦牛的采食当量,测定川西北青藏高原草甸区牧区成年母牦牛青草期放牧采食量(有机物质)。选用6头5岁空怀母牛作为试验牛,采用粪氮指数法用粪粗蛋白指数方程估测采食牧草有机物质消化率;用Cr2O3法估测日排粪量(干物质),预试期6d,收粪期6d,日喂药2次,日收粪3次,指示剂回收率100%(R1)和94%(R2);粪样按头按日测定干物质、有机物质、粗蛋白及铬含量。结果表明:日排粪量(干物质)2.82kg(R1)、2.66kg(R2);有机物质消化率74.6%;日采食量(有机物质)8.54kg(R2)、9.09kg(R1);采食量或排粪量与体重间无显著相关,体重组间差异不显著(P>0.05),提示体重因素可能对同龄成年母牦牛青草期采食量无影响;与报道比较,有机物质消化率估测值偏高。To determine the Maiwa female yak （non-pregnant and non-lactating） daily grass organic matter intakes （OMI） under grazing situations in green grass season （June）, grazing on subalpine-mead- ow-type pasture in northwest Sichuan province, Six 5-year-old female yak were selected with live weight （LW） of 197 kg on average and gradient of 10 kg, and then classified as low and high LW level. The pub- lished fecal crude protein index estimation （FCPI） for cattle fed forage-based diets was applied to estimate the diet OM digestibility （OMD）. The daily fecal output （FDM） was measured for each animal by using external marker Cr203, with twice daily dosing （over 12-d） and three-times-daily feces collecting over 6- days, assumed fecal 100% （R1） and 94% （R2） recovery of the marker. Fecal samples were analyzed for DM, Ash （OM = DM--Ash）, CP and Cr. The results showed 2.82 kg （R1） or 2.66 kg （R2） of FDM, 74.6% of OMD, 8.54 kg （R2） and 9.09 kg （R1） of OMI per animal. There was no significant （P〉O. 05） correlation of OMI （or FDM） with LW or difference of OMI （or FDM） between two LW groups, which might be explained as no effect of live weight on grazing intake in early grass period at a same adult age. Based on comparison with the published, the OMD value seemed to be overestimated. Further studies are needed to determine the OMD value and the FCPI equation validity for yak.

关 键 词：牦牛 天然草地 采食量 粪氮指数法 有机物质消化率 

分 类 号：S811.6[农业科学—畜牧学]