Harnessing Macroalgae from South Sulawesi: An In Vitro Approach to Enhancing Ruminant Efficiency and Methane Mitigation

Author : A. Natsir

Abstract :The livestock sector faces a dual challenge: enhancing ruminant productivity while mitigating methane (CH₄) emissions, a key contributor to climate change. This in vitro study evaluates the potential of seven macroalgae species from South Sulawesi, Indonesia, as feed additives to improve microbial efficiency and reduce CH₄ production in ruminants. The species assessed include four cultivated macroalgae (Eucheuma cottonii, Eucheuma denticulatum, Caulerpa sp., Gracilaria sp.) and three non-cultivated species (Halimynea sp., Caulerpa sp., Sargassum sp.), tested at inclusion levels of 0%, 5%, 10%, and 15%. A significant interaction between macroalgae type and inclusion level was observed, affecting microbial protein synthesis, bacterial and protozoal populations, and CH₄ emissions (p < 0.05). Saponin-rich species, particularly Caulerpa sp. (cultivated and non-cultivated) and Eucheuma denticulatum, demonstrated the greatest efficacy, enhancing microbial protein synthesis and bacterial populations while reducing protozoal activity and CH₄ emissions at 10%–15% inclusion levels. In contrast, tannin-rich species such as Sargassum sp. showed limited impact on CH₄ mitigation, underscoring the complex role of bioactive compounds in modulating rumen microbial dynamics. These findings highlight the promise of South Sulawesi’s macroalgae as a sustainable strategy for improving livestock productivity and minimizing environmental impacts. Future research should focus on optimizing the use of saponin-rich macroalgae and exploring synergistic effects among species to support global sustainability goals.

Keywords :Macroalgae, Feed Additives, Methane Mitigation, South Sulawesi, Saponins and tannis, In Vitro.

Conference Name :International Conference on Environment Science and Engineering (ICESE-25)

Conference Place Bristol, UK

Conference Date 24th Feb 2025