青藏高原东北缘不同草地类型牧草营养品质动态

Forage nutrition from different grassland types at different growth stages on the northeast margin of the Qinghai–Tibet Plateau

采用体外发酵法对玛曲县高寒草甸、沼泽化草甸、灌丛草地及山地草甸天然混合牧草青草期、返青前期和枯黄期的消失率和营养成分进行测定,旨在探讨玛曲县高寒草甸、沼泽化草甸、灌丛草地及山地草甸天然混合牧草不同生育期营养品质的变化,为不同草地类型及不同时期草地放牧家畜合理利用提供基础数据。结果表明,生育期对玛曲天然草地牧草干物质(DM)、粗蛋白(CP)、粗脂肪(EE)、酸性洗涤纤维(ADF)、中性洗涤纤维(NDF)、总能(GE)、钙(Ca)、磷(P)、NDF消失率、OM消失率和DM消失率有显著性影响(P <0.05),对粗灰分(Ash)无显著影响(P>0.05);草地类型对玛曲天然牧草的NDF、 Ash、 GE、 ADF消失率和OM消失率均有显著影响(P <0.05);生育期×草地类型交互作用对DM、CP、NDF、ADF、GE、Ca、P、NDF消失率和OM消失率均有显著影响(P <0.05)。研究结果显示,玛曲县天然牧草营养品质发育变化差异较大。

The purpose of this study was to explore the changes in the nutritional quality of the natural mixed pasture in an alpine meadow, swampy meadow, shrubland, and mountain meadow in Maqu County, and to provide basic data for the rational feeding of grazing livestock in different periods for specific pasture types. Study by the in vitro fermentation method was used to determine the digestibility and nutrient content of natural mixed herbage at different growth stages, including the grass period, early turning green period, and withering period in Maqu County, in an alpine meadow, swamp meadow, shrubland, and mountain meadow. The results are as follows: The growth period had significant influence on the DM, CP, EE, NDF, ADF, GE, Ca, P, NDF digestibility, OM digestibility, and DM digestibility (P < 0.05), but did not significantly affect the ash (P > 0.05);the grassland types had significant effects on the digestibility of ADF, ash, GE, ADF, and the digestibility of OM in Maqu natural grasslands (P < 0.05);and the interaction between growth stages and grassland types had significant effects on DM, CP, NDF, ADF, GE, Ca, P, NDF digestibility, and OM digestibility (P < 0.05). This showed that the seasonal difference in nutritional quality of herbage in Maqu is large.