Abstract
With increasing interest in feed based methane mitigation strategies, fueled by local legal directives aimed at methane production from the agricultural sector in California, identifying local sources of biological feed additives will be critical in keeping the implementation of these strategies affordable. In a recent study, the red alga Asparagopsis taxiformis stood out as the most effective species of seaweed to reduce methane production from enteric fermentation. Due to the potential differences in effectiveness based on the location from where A. taxiformis is collected and the financial burden of collection and transport, we tested the potential of A. taxiformis, as well as the brown seaweed Zonaria farlowii collected in the nearshore waters off Santa Catalina Island, CA, USA, for their ability to mitigate methane production during in-vitro rumen fermentation. At a dose rate of 5% dry matter (DM), A. taxiformis reduced methane production by 74% (p ≤ 0.01) and Z. farlowii reduced methane production by 11% (p ≤ 0.04) after 48 hours and 24 hours of in-vitro rumen fermentation respectively. The methane reducing effect of A. taxiformis and Z. farlowii described here make these local macroalgae promising candidates for biotic methane mitigation strategies in the largest milk producing state in the US. To determine their real potential as methane mitigating feed supplements in the dairy industry, their effect in-vivo requires investigation.
Footnotes
Conflict of interest: The authors declare to have no conflict of interest.
Funding: Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s). This work was supported through funds from the College of Agricultural and Environmental Sciences at the University of California, Davis, by Elm Innovations and by the Hellman Foundation. Maddelyn C. Harden was supported by ARPA-E (Contract# 1726-1513) and Sergey V. Nuzhdin was supported by a Wyatt Foundation gift.
cgbrooke{at}ucdavis.edu, bmroque{at}ucdavis.edu, nnajafi{at}ucdavis.edu, mdcgonzalez{at}ucdavis.edu, apfefferlen{at}ucdavis.edu, vndeanda{at}ucdavis.edu, dginsbur{at}usc.edu, mharden{at}usc.edu, snuzhdin{at}usc.edu, jsalwen{at}standford.edu, ekebreab{at}ucdavis.edu, mhess{at}ucdavis.edu