大型海藻作为饲料添加剂实现反刍动物肠道甲烷减排的潜力与挑战

doi:10.1016/j.jia.2024.09.036

摘要/Abstract

摘要：

降低反刍动物肠道甲烷排放是应对气候变化的重要举措之一。自研究人员首次发现大型藻类具备降低肠道甲烷排放的潜力以来，使用大型海藻作为一种新型饲料添加剂来抑制反刍动物肠道甲烷排放在近些年得到了全球广泛关注。由于含有相对较高浓度的三溴甲烷，Asparagopsis taxiformis（紫衫状海门冬）成为首选的目标物种。三溴甲烷作为一种卤代甲烷结构类似物，能够特异性地抑制瘤胃产甲烷菌中辅酶M甲基转移酶的活性，从而阻断甲烷生成。但是需要注意的是，三溴甲烷也是一种潜在的有毒物质和消耗臭氧层的大气污染物。当前的研究重点集中在饲喂富含三溴甲烷的海藻对反刍动物肠道甲烷减排效果、生产性能和安全性的影响，以及大规模海藻种植对大气环境的影响。未来在开发海藻作为甲烷减排产品时，需要关注那些具备甲烷减排能力但同时三溴甲烷含量低的物种，例如Bonnemaisonia hamifera、Dictyota bartayresii和Cystoseira trinodis。此外，海藻中富含多种生物活性物质，这些活性物质通常具有抗菌、抗炎等生理特性，但关于这些生物活性物质在甲烷减排中的效果研究仍然缺乏。因此，需要进一步深入研究以鉴定出更多潜在功能的生物活性化合物。作为一个新的研究热点，海藻想要被开发为成熟的反刍动物饲料添加剂产品仍面临一些挑战和亟需解决的问题，例如重金属（碘和溴）和三溴甲烷在乳制品和肉制品中的残留问题，以及海藻种植、收获、保存和加工等产业链问题。综上，尽管部分海藻已经表现出很好的甲烷减排效果，但其作为商业饲料添加剂的应用仍受到安全性、成本、政策激励和法律法规等因素的影响。

Abstract:

Cutting farming-related methane emissions from ruminants is critical in the battle against climate change. Since scientists initially investigated the potential of marine macroalgae to reduce methane emissions, using seaweeds as an anti-methanogenic feed additive has become prevailing in recent years. Asparagopsis taxiformis is the preferred species because it contains a relatively higher concentration of bromoform. As a type of halogenated methane analogue, bromoform contained in A. taxiformis can specifically inhibit the activity of coenzyme M methyltransferase, thereby blocking the ruminal methanogenesis. However, bromoform is a potential toxin and ozone-depleting substance. In response, current research focuses on the effects of bromoform-enriched seaweed supplementation on ruminant productivity and safety, as well as the impact of large-scale cultivation of seaweeds on the atmospheric environment. The current research on seaweed still needs to be improved, especially in developing more species with low bromoform content, such as Bonnemaisonia hamifera, Dictyota bartayresii, and Cystoseira trinodis. Otherwise, seaweed is rich in bioactive substances and exhibits antibacterial, anti-inflammatory, and other physiological properties, but research on the role of these bioactive compounds in methane emissions is lacking. It is worthy of deeper investigation to identify more potential bioactive compounds. As a new focus of attention, seaweed has attracted the interest of many scientists. Nevertheless, seaweed still faces some challenges as a feed additive to ruminants, such as the residues of heavy metals (iodine and bromine) and bromoform in milk or meat, as well as the establishment of a supply chain for seaweed cultivation, preservation, and processing. We have concluded that the methane-reducing efficacy of seaweed is indisputable. However, its application as a commercial feed additive is still influenced by factors such as safety, costs, policy incentives, and regulations.

Key words: seaweed , Asparagopsis taxiformis , bromoform , methane emission , ruminant

. 大型海藻作为饲料添加剂实现反刍动物肠道甲烷减排的潜力与挑战[J]. Journal of Integrative Agriculture, 2025, 24(4): 1327-1341.

Yunlong Liu, Mi Zhou, Qiyu Diao, Tao Ma, Yan Tu. Seaweed as a feed additive to mitigate enteric methane emissions in ruminants: Opportunities and challenges[J]. Journal of Integrative Agriculture, 2025, 24(4): 1327-1341.

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