This study [1] does indeed not reference N2O. So this make me suspicious: The garlic study [2], states: "Garlic contains allicin, diallylsulide, dialyldisulfid

This study [1] does indeed not reference N2O. So this make me suspicious: The garlic study [2], states: "Garlic contains allicin, diallylsulide, dialyldisulfide and allyl mercaptan, which affect rumen methanogens, decreasing rumen CH4 and acetate production and increasing rumen propionate and butyrate production (Busquet et al., 2005)." Allicin is not referenced in the sea-weed study. One would have to study the exact mechanism [3], to be conclusive. [1]: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0085289 https://journals.plos.org/plosone/article?id=10.1371/journal... [2]: http://www.thecattlesite.com/articles/2858/effect-of-garlic-oil-on-methane-production-in-lactating-buffalo/ http://www.thecattlesite.com/articles/2858/effect-of-garlic-... [3]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4714447/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4714447/