青海矮生嵩草和垂穗披碱草草地牧草营养价值与载畜量的比较

摘要

In order to know the nutritional value and carrying capacity of Kobresia humilis and Elymus nutans Griseb pasture in Henan county,Qinghai province,three yaks were chosen to provide rumen solution,and used conventional nutritional analysis method and in vitro with gas production method to evaluate forage nutritional value of Kobresia humilis and Elymus nutans Griseb grassland of Qilong pastureland in Henan county.The results showed that the yield of fresh forage(217.90 g/m2)of Kobresia humilis were significantly lower than Elymus nutans Griseb(317.71g/m2).The edible forage of Kobresia humilis and Elymus nutans Griseb grassland accounted for 92% and 94% of the dry forage,respectively. The contents of DM(94.67%),EE(3.02%),P(0.16%)of Elymus nutans Griseb were significantly higher than those of Kobresia humilis,but Ca(0.70%) and ADF(32.78%)contents of Kobresia humilis were significantly higher than those of Elymus nutans Griseb. G as production of Kobresia humilis and Elymus nutans Griseb grassland pasture were 65.45 and 71.78 mL,NH3-N were 0.988 and 0.656 mg/L, pH value were 5.92 and 5.93,DOM were 71.10% and 77.16%,DE were 11.93 and 12.82 MJ/kg,ME were 10.73 and 11.66 MJ/kg,respectively.DCP carrying capacity of Kobresia humilis and Elymus nutans Griseb pasture were 4.51 and 5.41 SU/hm2,ME carrying capacity were 3.83 and 4.68 SU/hm2,amount carrying capacity were 2.25 and 2.53 SU/hm2,respectively.So,it was reasonable to take into considered the yield of edible forage when estimate carrying capacity(amount carrying capacity).If economic conditions permit,grazing and feeding was more reasonable.%为研究青海省河南县矮生嵩草、垂穗披碱草草地牧草营养价值与载畜量,选用3头装有永久性瘤胃瘘管的牦牛作为供试动物,采用概略养分分析法和体外产气法,评定了河南县启龙牧场矮生嵩草、垂穗披碱草草地牧草营养价值.结果显示:矮生嵩草草地型的鲜草产量为217.90 g/m2,显著低于垂穗披碱草草地型的鲜草产量(317.71 g/m2)(P<0.05),矮生嵩草草地型和垂穗披碱草草地型牧草的可食草产量分别占干草产量的92%和94%.垂穗披碱草草地型牧草干物质(DM) (94.67%)、粗脂肪(EE)(3.02%)、磷(P)(0.16%)含量显著高于矮生嵩草草地型(P<0.05).但是钙(Ca)(0.70%)和酸性洗涤纤维(ADF)(32.78%)含量矮生嵩草草地型显著高于垂穗披碱草草地型.矮生嵩草、垂穗披碱草草地型牧草体外发酵产气量分别为65.45、71.78 mL,NH3-N含量分别为0.988、0.656 mg/L,pH 值分别为5.92、5.93,有机物质消化率(DOM)分别为71.10%、77.16%,消化能(DE)分别为11.93、12.82 MJ/kg,代谢能(ME)分别为10.73、11.66 MJ/kg.矮生嵩草、垂穗披碱草草地型牧草的可消化蛋白载畜量分别为4.51、5.41 SU/hm2,代谢能载畜量分别为3.83、4.68 SU/hm2,数量载畜量分别为2.25、2.53 SU/hm2.综上,暖季估计载畜量应首先考虑可食牧草产量,即数量载畜量较为合理,如果经济条件允许,放牧加补饲的方式更为合理.