Universidad Nacional Agraria La Molina, Av. La Molina s/n, La Molina, Lima, Peru.
Instituto Nacional de Innovación Agraria, Av. La Molina n°1981, La Molina, Lima, Peru.
Trop Anim Health Prod. 2022 Mar 26;54(2):144. doi: 10.1007/s11250-022-03146-2.
The objective of the study was to determine enteric methane emissions using the sulfur hexafluoride (SF) technique and comparing with The Intergovernmental Panel on Climate Change (IPCC) methodology in lactating cows (LC) and dry cows (DC) in the Peruvian highlands. Enteric methane (CH) emissions were measured on 5 LC and 6 DC Brown Swiss in a grazing system without concentrate. Forages samples were collected and analyzed for dry matter, crude protein, and neutral detergent fiber. Milk samples were collected and analyzed for fat, crude protein, and lactose to estimate energy-corrected milk. Animal intakes were measured using the external marker titanium dioxide (production of feces) and crude protein in feces (organic digestibility of the feed) and estimated by using performance data. The enteric methane emissions of LC were higher than methane emissions of DC (325 and 266 g CH/cow/day for LC and DC, respectively (P < 0.001)). Methane emissions were 358.5 g CH/day by SF technique and 291.6 g CH/day by IPCC methodology for LC and 337.4 g CH/day by SF technique and 195.8 g CH/day by IPCC methodology for DC. Methane yields measured by SF were higher than methane yields estimated by IPCC methodology (29 g CH/kg DM and 22 g CH/kg DM using SF technique and IPCC methodology, respectively (P < 0.001)). Methane yields were differently for all expressions by physiological stage and method. The methane conversion factor (Ym) was 9.7% for LC and 9.6% for DC. Methane intensities were similar by method (P > 0.05). It was concluded that IPCC's methodology underestimate the CH emissions of dairy systems in the Peruvian Andes; therefore, in order to obtain precise Ym, direct measurements of enteric CH in the different regions of Peruvian highlands are required.
本研究旨在利用六氟化硫（SF）技术测定泌乳奶牛（LC）和干奶牛（DC）的肠道甲烷排放，并与政府间气候变化专门委员会（IPCC）方法进行比较。在秘鲁高地的放牧系统中，对 5 头 LC 和 6 头 DC 棕色瑞士奶牛进行了肠道甲烷（CH）排放测量，未添加精料。收集并分析饲草样本的干物质、粗蛋白和中性洗涤剂纤维。收集并分析牛奶样本以测定脂肪、粗蛋白和乳糖，以估计能量校正奶。通过外部标记二氧化钛（粪便的产生）和粪便中的粗蛋白（饲料的有机消化率）测量动物采食量，并利用生产性能数据进行估算。LC 的肠道甲烷排放量高于 DC（LC 和 DC 的甲烷排放量分别为 325 和 266g CH/奶牛/天（P<0.001））。SF 技术测定的甲烷排放量为 358.5g CH/天，IPCC 方法为 291.6g CH/天，LC 的 SF 技术为 337.4g CH/天，IPCC 方法为 195.8g CH/天。SF 技术和 IPCC 方法分别测定的甲烷产率为 29g CH/kg DM 和 22g CH/kg DM（P<0.001）。SF 技术和 IPCC 方法测定的甲烷产率在不同生理阶段和方法之间存在差异。LC 的甲烷转化因子（Ym）为 9.7%，DC 为 9.6%。方法间的甲烷强度相似（P>0.05）。综上所述，IPCC 方法低估了秘鲁安第斯地区奶牛系统的 CH 排放量；因此，为了获得精确的 Ym，需要在秘鲁高地的不同地区直接测量肠道 CH。
