摘要
为了进一步探讨饱和链烷技术在典型草原自由放牧家畜中的应用,定量研究自由放牧绵羊食性及食量,于2004年6-9月在中国科学院内蒙古草原生态系统定位研究站放牧样地进行试验,选择体重及体况相近、健康无病的二岁羯羊(内蒙古细毛羊×蒙古羊)60只,按体重(36.9±2.6)kg聚类分组,设置6种放牧率(0,1.33,2.67,4.00,5.33和6.67羊/hm2)的轮牧实验,绵羊采食量的测定选择放牧率为1.33,4.00和6.67羊/hm2的处理,试验开始,每只羊投喂1粒QSM饱和链烷缓释胶囊。食性测定选用全部的放牧率进行,同时辅助全粪法、扣笼法一同评价。试验期内定期收集试验地牧草样品及绵羊粪便样品,使用气相色谱分析牧草和粪样中的链烷含量,应用链烷技术估测放牧绵羊的排粪量、牧草采食比例和干物质采食量。结果表明,植物链烷模式存在种间差异,运用链烷技术估测的排粪量和实际测得排粪量差异不显著(P>0.05),放牧绵羊主要采食7~9种牧草,且不同放牧季节不同放牧率绵羊采食的牧草种类和比例不同,但采食量差异不显著(P>0.05)。本研究表明,运用链烷技术结合扣笼方法可以估测天然草地自由放牧家畜牧草的采食比例、干物质采食量和排粪量。
In order to probe into the application of n-alkanes as markers for estimating diet composition and herbage intake of free grazing herbivores in rangeland,a rotational grazing experiment was conducted from 20th June to 20th September at 2004,at the Inner Mongolia Grassland Ecosystem Research Station of Chinese Academy of Sciences.Sixty 2-year-old wethers(Inner Mongolia fine wool sheep × Inner Mongolia sheep) were selected and allocated to the 5 stocking rates(1.33,2.67,4.00,5.33 and 6.67 sheep/ha) without significant difference(P0.05) in body weight(36.9±2.6) kg to evaluate the effect of stocking rates and grazing seasons on dietary composition and intake of grazing sheep,at the same time,total feces of each sheep were collected using bag attached to body and 10 cages(1.2 m×1.2 m) were arranged randomly within each paddock to assess approximately how many species ingested by grazing sheep based on the difference between aboveground biomass of each species inside and outside cages after grazing.Only the stocking rates of 1.33,4.00 and 6.67 sheep/ha were dosed with one Artificial QSM Alkane Controlled Released Capsules(Made in New Zealand Captec Company) at the beginning of the experiment each time.The samples of herbage and feces were collected daily for 7 days and dried for n-alkane concentration analysis using gas chromatography to estimate the feces output,diet composition,and herbage intake of sheep.The results show that there was a difference in concentration of n-alkanes among each plant species,and there were no significant difference(P0.05) between estimated feces output using n-alkane technique and the actual values by sheep.7-9 species forages were ingested by sheep,and plant species and its proportion were eaten by sheep were different at different stocking rates and grazing season,but their intake did not differ significantly(P0.05).In conclusion,n-alkanes technique can estimate accurately and easily dietary composition and intake of grazing sheep when used in combination with the cage technique in natural temperate grasslands.
出处
《草业学报》
CSCD
北大核心
2013年第2期71-79,共9页
Acta Prataculturae Sinica
基金
中国科学院"百人计划"优先资助项目(292005312D1102626)
中国科学院知识创新工程方向性项目(KSCX2-YW-N-040)资助
关键词
链烷技术
绵羊
食性
食量
放牧率
典型草原
n-alkane technique
sheep
diet composition
herbage intake
stocking rates
typical steppe