The role of seaweed as a potential dietary supplementation for enteric methane mitigation in ruminants: Challenges and opportunities

Abstract

Seaweeds are macroalgae, which can be of many different morphologies, sizes, colors, and chemical profiles. They include brown, red, and green seaweeds. Brown seaweeds have been more investigated and exploited in comparison to other seaweed types for their use in animal feeding studies due to their large sizes and ease of harvesting. Recent in vitro and in vivo studies suggest that plant secondary compound-containing seaweeds (e.g., halogenated compounds, phlorotannins, etc.) have the potential to mitigate enteric methane (CH 4 ) emissions from ruminants when added to the diets of beef and dairy cattle. Red seaweeds including Asparagopsis spp. are rich in crude protein and halogenated compounds compared to brown and green seaweeds. When halogenated-containing red seaweeds are used as the active ingredient in ruminant diets, bromoform concentration can be used as an indicator of anti-methanogenic properties. Phlorotannin-containing brown seaweed has also the potential to decrease CH 4 production. However, numerous studies examined the possible anti-methanogenic effects of marine seaweeds with inconsistent results. This work reviews existing data associated with seaweeds and in vitro and in vivo rumen fermentation, animal performance, and enteric CH 4 emissions in ruminants. Increased understanding of the seaweed supplementation related to rumen fermentation and its effect on animal performance and CH 4 emissions in ruminants may lead to novel strategies aimed at reducing greenhouse gas emissions while improving animal productivity.

Chemical composition of brown and red algae from Kelapa Beach, Tuban, East Java and their potential as ruminant feed

“…The crude protein of brown algae (12.28 and 12.57%) is higher than red algae (8.55-11.72%). This result is different as reported by Min et al [15], red seaweed contained the highest amount of crude protein (18-38%) than brown and green algae. This condition is due to the different species, habitats, and the harvesting time of the algae.…”

“…The same result was reported by some researchers that the crude protein of Laminaria Sp. around 9.8-16.6% DM basis [15], Padina australis at 13.39% w/w [17], Eucheuma cottonii at 9.76% dry weight [18], and Gracilaria Sp. at 9.36% dry weight [19].…”

Image-Based Analysis and Quantification of Biofouling in Cultures of the Red Alga Asparagopsis taxiformis

“…The red algal genus Asparagopsis when fed in small quantities has been shown to be highly effective at reducing methane emissions associated with enteric fermentation (up to 90%). Results have been consistent both in vitro and in live ruminant trials (Kinley et al 2016(Kinley et al , 2020Roque et al 2021;Min et al 2021), yielding no apparent trade-offs in product quality, animal production or any negative environmental effects (Glasson et al 2022). However, to date, the Asparagopsis used in these trials has been primarily wild-harvested and as such it is not commercially available (Nin-Pratt et al 2022).…”

Fermentación ruminal in vitro y producción de AGVS, metano y bióxido de carbono con la inclusión de extractos de plantas del semidesierto zacatecano.

“…Las algas marinas, también conocidas como macroalgas, incluyendo las marrones (Phaeophyta), rojas (Rhodophyta) y (Rhodophyta) y verdes (Chlorophyta), se han convertido en aditivos alimentarios preferibles por sus propiedades antimetanogénicas (Vijn et al, 2020;Roque et al, 2021). Varios estudios in vitro de suplementos de algas marinas mostraron una correlación negativa con la generación de metano especialmente con Asparagopsis taxiformis (Abbott et al, 2020;Maia, 2016;Min et al, 2021) y sus compañeras Asparagopsis sppreduce la emisión de metano in vivo del 50% a más del 80% en el ganado lechero (Roque et al, 2019;Li Bañuelos-Valenzuela y Delgadillo-Ruiz et al, 2016). Los prebióticos como el quitosano, la inulina y los productos de levadura también pueden limitar las emisiones de metano entérico modificando la estructura de la comunidad bacteriana del rumen (Tong et al, 2020;Seankamsorn et al, 2020).…”