Department of Animal Science, The Pennsylvania State University, University Park 16802.
Department of Animal Science, The Pennsylvania State University, University Park 16802.
J Dairy Sci. 2022 Oct;105(10):8543-8557. doi: 10.3168/jds.2021-21398. Epub 2022 Jul 19.
Intensive research in the past decade has resulted in a better understanding of factors driving enteric methane (CH) emissions in ruminants. Meta-analyses of large databases, developed through the GLOBAL NETWORK project, have identified successful strategies for mitigation of CH emissions. Methane inhibitors, alternative electron sinks, vegetable oils and oilseeds, and tanniferous forages are among the recommended strategies for mitigating CH emissions from dairy and beef cattle and small ruminants. These strategies were also effective in decreasing CH emissions yield and intensity. However, a higher inclusion rate of oils may negatively affect feed intake, rumen function, and animal performance, specifically milk components in dairy cows. In the case of nitrates (electron sinks), concerns with animal health may be impeding their adoption in practice, and potential emission trade-offs have to be considered. Tannins and tanniferous forages may have a negative effect on nutrient digestibility, and more research is needed to confirm their effects on overall animal performance in long-term experiments with high-producing animals. A meta-analysis of studies with dairy cows fed the CH inhibitor 3-nitrooxypropanol (3-NOP) at the Pennsylvania State University showed (1) a consistent 28 to 32% decrease in daily CH emissions or emissions yield and intensity; (2) no effect on dry matter intake, milk production, body weight, or body weight change, and a slight increase in milk fat concentration and yield (0.19 percentage units and 90 g/d, respectively); 3-NOP also appears to increase milk urea nitrogen concentration; (3) an exponential decrease in the mitigation effect of the inhibitor with increasing its dose (from 40 to 200 mg/kg of feed dry matter, corresponding to 3-NOP intake of 1 to 4.8 g/cow per day); and (4) a potential decrease in the efficacy of 3-NOP over time, which needs to be further investigated in long-term, full-lactation or multiple-lactation studies. The red macroalga Asparagopsis taxiformis has a strong CH mitigation effect, but studies are needed to determine its feasibility, long-term efficacy, and effects on animal production and health. We concluded that widespread adoption of mitigation strategies with proven effectiveness by the livestock industries will depend on cost, government policies and incentives, and willingness of consumers to pay a higher price for animal products with decreased carbon footprint.
在过去的十年中,人们对驱动反刍动物肠道甲烷(CH)排放的因素进行了深入研究,因此对其有了更好的理解。通过“全球网络”项目开发的大型数据库的荟萃分析已经确定了减少 CH 排放的成功策略。甲烷抑制剂、替代电子受体、植物油和油籽以及富含单宁的饲料是减少奶牛和肉牛以及小反刍动物 CH 排放的推荐策略。这些策略也能有效降低 CH 排放的产量和强度。然而,较高的油用量可能会对饲料采食量、瘤胃功能和动物生产性能产生负面影响,特别是对奶牛的牛奶成分。对于硝酸盐(电子受体),人们对动物健康的担忧可能会阻碍其在实践中的应用,并且需要考虑潜在的排放权衡。单宁和富含单宁的饲料可能会对养分消化率产生负面影响,因此需要进行更多的研究以确认它们在高产动物的长期试验中对动物整体生产性能的影响。宾夕法尼亚州立大学对饲喂 CH 抑制剂 3-硝基氧基丙醇(3-NOP)的奶牛进行的研究的荟萃分析表明:(1)每日 CH 排放量或排放量和强度持续减少 28%至 32%;(2)对干物质采食量、牛奶产量、体重或体重变化没有影响,并且牛奶脂肪浓度和产量略有增加(分别为 0.19 个百分点和 90 克/天);3-NOP 似乎还增加了牛奶尿素氮浓度;(3)随着抑制剂剂量的增加(从 40 至 200 毫克/千克饲料干物质,相当于 3-NOP 每天摄入量为 1 至 4.8 克/头),抑制剂的缓解效果呈指数下降;(4)随着时间的推移,3-NOP 的功效可能会降低,这需要在长期、全泌乳期或多次泌乳期研究中进一步调查。红藻龙须菜具有很强的 CH 减排效果,但需要研究确定其可行性、长期效果以及对动物生产和健康的影响。我们得出的结论是,畜牧业广泛采用经证实有效的减排策略将取决于成本、政府政策和激励措施,以及消费者是否愿意为具有较低碳足迹的动物产品支付更高的价格。