A recent study published in the peer-reviewed journal Animal Feed Science and Technology has revealed that feeding cattle whole Asparagopsis armata seaweed is significantly more effective in reducing methane emissions than using bromoform, its isolated bioactive component. Conducted in vitro, the research was funded by CH4 Global, a grower of Asparagopsis, and highlights a promising avenue for mitigating the environmental impact of livestock farming.
The study compared the methane reduction potential of whole Asparagopsis armata seaweed to that of pure bromoform in rumen fluid sourced from Holstein cows. The results were striking: when included at just 0.5% of the diet, whole Asparagopsis led to a remarkable 95.6% reduction in methane emissions, whereas an equivalent dose of bromoform alone achieved only a 59.6% reduction. This discrepancy suggests that the whole seaweed contains additional bioactive compounds that enhance its methane-busting capabilities, contributing to about 40% of the observed reduction beyond what bromoform alone could achieve.
The implications of these findings are significant for the livestock industry, particularly given the urgent need to address methane emissions, a potent greenhouse gas generated not only from manure decomposition but also from the digestive processes of ruminants. Methane is produced in the rumen, where complex carbohydrates are broken down by microbes, leading to gas production that is converted into methane by methanogens.
While some companies are focused on extracting bromoform from seaweed or synthesizing it chemically, the study’s authors argue that these methods are less effective than using the whole seaweed. They emphasize that natural products are more likely to gain acceptance among consumers compared to synthetic alternatives. Furthermore, at the recommended inclusion levels of Asparagopsis biomass, bromoform levels in animal products are undetectable, ensuring both animal health and product quality.
Despite the promising results, scaling the cultivation of Asparagopsis seaweed presents its own challenges. Startups in the livestock methane reduction arena are exploring various strategies, including vaccines, breeding programs for lower methane-producing animals, and genetic editing of rumen microbes. For instance, Number8 Bio, a Sydney-based startup, has pivoted from producing bromoform via microbial fermentation to focusing on synthetic chemistry, arguing that low cost and high efficacy are paramount in this market.
Conversely, Dr. Colin South, CEO of ArkeaBio, believes that developing a vaccine could represent the most efficient and scalable solution for methane mitigation. He points out that the logistics of producing and distributing millions of tons of seaweed would be a complex and time-consuming endeavor compared to the relatively straightforward process of manufacturing vaccines.
Dr. Steve Meller, CEO of CH4 Global, views the study’s results as validation of his firm’s approach. He asserts that the findings not only support the performance advantage of whole Asparagopsis over synthetic compounds but also highlight the cost-effectiveness of their product, Methane Tamer. By utilizing whole seaweed, they can achieve superior methane reduction with a lower dosage, making it an economically viable option for farmers.
As the agricultural sector grapples with the challenge of reducing methane emissions, the study underscores the potential of whole Asparagopsis armata seaweed as a natural feed supplement. It opens the door to more sustainable livestock farming practices, while also posing questions about the feasibility of scaling up seaweed production in the face of competing technological solutions.