Institute for Future Farming Systems, CQUniversity, Rockhampton, QLD, Australia.
DIT AgTech, Wilsonton, QLD, Australia.
J Anim Sci. 2024 Jan 3;102. doi: 10.1093/jas/skae315.
Two experiments were conducted to determine the potential for the essential oil blend Agolin Ruminant L (Agolin) to reduce enteric methane (CH4) emissions from beef cattle when delivered via drinking water. Experiment 1 evaluated aqueous solutions of Agolin (50 mg/L) and a nonprotein nitrogen and mineral solution (uPRO ORANGE [uPRO]; 1.7 mL/L) individually and in combination, where Agolin was added to concentrated uPRO at 3%, 4.5%, and 6% Agolin (w/w) prior to dilution with water at 1.7 mL/L, for a total of 5 treatments. These were incubated for 48 h with a medium-quality Rhodes grass (Chloris gayana) hay substrate, with gas production, CH4 concentration in gas, and digestibility measured in vitro. In experiment 2, Droughtmaster steers (n = 24) were fed a basal diet of Rhodes grass hay and were allocated to 1 of 3 water treatments (n = 8 per treatment) supplemented with either uPRO (2.27 mL uPRO/L water), or 1 of 2 inclusion rates of Agolin in combination with uPRO (2.27 mL uPRO and 6 µL Agolin/L water or 2.27 mL uPRO and 24 µL Agolin/L water) with enteric CH4 emissions, feed and water intake, and live-weight gain (LWG) measured over 56 d. In experiment 1, the inclusion of Agolin in uPRO at 6% (w/w) resulted in a reduction in CH4 production (15.8%; P = 0.003) and the proportion of CH4 in the gas produced (24.5%; P < 0.001). In experiment 2, steers consuming the lower quantity of Agolin via drinking water had a 16.4% (P = 0.0027) reduction in CH4 production over the experiment, declining from 140 g/d during week 1 to 117 g/d in week 8. This inclusion rate of Agolin in the drinking water also resulted in a 25 g (17.6%) CH4/d decrease in emissions by steers compared to control steers (P = 0.0205). However, no significant differences in CH4 yield (g CH4/kg dry matter intake), or CH4 intensity (g CH4/kg LWG) by steers were observed between treatments. These results demonstrated that Agolin reduces CH4 emissions when mixed in an aqueous solution under in vitro and in vivo conditions, providing a potential method to reduce enteric CH4 emissions from cattle in extensive production systems.
进行了两项实验，以确定在饮用水中添加 Agolin Ruminant L（Agolin）精油混合物是否可以减少肉牛的肠道甲烷（CH4）排放。实验 1 评估了 Agolin（50mg/L）和非蛋白氮和矿物质溶液（uPRO ORANGE [uPRO]；1.7mL/L）的水溶液，单独和组合使用，Agolin 以 3%、4.5%和 6%（w/w）的比例添加到浓缩 uPRO 中，然后用水稀释至 1.7mL/L，共 5 种处理。将这些混合物与中等质量的罗兹草（Chloris gayana）干草底物一起在 48 小时内孵育，测量体外产气量、气体中 CH4 浓度和消化率。在实验 2 中，将抗旱牛（Droughtmaster）（n=24）喂食罗兹草干草的基础日粮，并将其分配到 3 种水治疗组（每组 8 头）之一，其中添加 uPRO（2.27mL uPRO/L 水）或 Agolin 与 uPRO 的 2 种添加率之一（2.27mL uPRO 和 6µL Agolin/L 水或 2.27mL uPRO 和 24µL Agolin/L 水），测量肠道 CH4 排放、饲料和水摄入量以及活体增重（LWG），共 56 天。在实验 1 中，在 uPRO 中添加 6%（w/w）的 Agolin 导致 CH4 产量降低（15.8%；P=0.003）和产生的气体中 CH4 比例降低（24.5%；P<0.001）。在实验 2 中，通过饮用水摄入较低量 Agolin 的牛在实验过程中 CH4 产量减少了 16.4%（P=0.0027），从第 1 周的 140g/d 下降到第 8 周的 117g/d。与对照牛相比，这种饮水水中的 Agolin 添加率也使牛的 CH4 排放量减少了 25g（17.6%）（P=0.0205）。然而，牛之间的 CH4 产量（g CH4/kg 干物质摄入量）或 CH4 强度（g CH4/kg LWG）没有观察到处理之间的差异。这些结果表明，Agolin 在体外和体内条件下混合在水溶液中可减少 CH4 排放，为减少集约生产系统中牛的肠道 CH4 排放提供了一种潜在方法。
