Novel Strategies for enteric methane abatement

Summary

The effectiveness of dietary nitrate inclusion and of elimination on rumen protozoa to achieve reduced enteric methane emissions from ruminants was assessed. Dietary nitrate is a highly effective abatement technology, reducing methane emissions in proportion to the dose added.
It can safely be delivered in processed feeds and in lick-blocks at levels which deliver quantifiable emissions reduction. Ruminal nitrate reduction is extremely rapid and emission levels return to normal within 3h of nitrate feeding. Providing nitrate in pelleted feeds and in lick blocks both reduced methane production, warranting its development as a CFI methodology. Methane yield of cattle without rumen protozoa did not differ from that of untreated cattle, but protozoa-free cattle were 30kg heavier than untreated counterparts by completion of the study. Bioactive compounds from a range of chemical families were assessed for antiprotozoal action in the laboratory. The lead compound showed no efficacy in sheep.