Orcasberro M Soledad, Loza Cecilia, Gere José, Soca Pablo, Picasso Valentín, Astigarraga Laura
Departamento de Producción Animal y Pasturas, Facultad de Agronomía, Universidad de la Republica, Montevideo 12900, Uruguay.
Unidad de Investigación y Desarrollo de las Ingenierías (UTNBA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires C1179AAQ, Argentina.
Animals (Basel). 2021 Mar 19;11(3):882. doi: 10.3390/ani11030882.
The aim of this study was to measure methane emissions (CH) and herbage intake, and, on the basis of these results, obtain the methane yield (MY, methane yield as g CH/kg dry matter intake (DMI) and Ym, methane yield as a percentage of Gross Energy intake), from beef cows grazing on native grasslands. We used forty pregnant heifers, with two treatments of herbage allowance (HA) adjusted seasonally (8 and 5 kg dry matter (DM)/kg cattle live weight (LW), on average), during autumn, winter and spring. Methane emissions (207 g CH/d), organic matter intake (OMI, 7.7 kg organic matter (OM)/d), MY (23.6 g CH/kg DMI) and Ym (7.4%), were similar between treatments. On the other hand, all variables had a marked increase in spring (10.8 kg OM/d and 312 g CH/d), except for Ym. The methane emission factor from Intergovernmental Panel on Climate Change (IPCC) Tier 2 estimated with these results was 78 kg CH/head/year. The results show that methane emissions and intake were influenced by the season, but not by the HA analyzed in this study. This information for cow-calf systems in native grasslands in Uruguay can be used in National greenhouse gases (GHG) inventories, representing a relevant contribution to global GHG inventories.
本研究的目的是测量甲烷排放量（CH）和牧草摄入量，并基于这些结果，得出在天然草地上放牧的肉牛的甲烷产量（MY，以克CH/千克干物质摄入量（DMI）表示的甲烷产量）和Ym（以总能摄入量的百分比表示的甲烷产量）。我们使用了40头怀孕的小母牛，在秋季、冬季和春季进行了两种季节性调整牧草供应量（HA）的处理（平均分别为8和5千克干物质（DM）/千克牛体重（LW））。处理之间的甲烷排放量（207克CH/天）、有机物质摄入量（OMI，7.7千克有机物质（OM）/天）、MY（23.6克CH/千克DMI）和Ym（7.4%）相似。另一方面，除Ym外，所有变量在春季均显著增加（10.8千克OM/天和312克CH/天）。根据这些结果估算的政府间气候变化专门委员会（IPCC）第2层的甲烷排放因子为78千克CH/头/年。结果表明，甲烷排放和摄入量受季节影响，但不受本研究中分析的HA的影响。乌拉圭天然草地牛犊系统的这些信息可用于国家温室气体（GHG）清单，对全球GHG清单做出相关贡献。
