Guy Trafford is following the latest developments on controlling livestock methane, but remembers the DCD 'breakthrough' which stumbled on consumer perception rather than actual risk. He counsels leaving no stone unturned

Reading the recent Angus Kebbell article, one in particular associated comment brought me to reminisce over past ‘breakthroughs’ and notably the one around DCD’s and reducing nitrate flows through the soils and resulting benefits to the environment.

At the time ‘we’ could see no downsides and plenty of benefits. However, perhaps we were a little hasty in these assumptions.

After some applications DCD’s were detected in both milk and waterways, not to any great degree and not associated with any measurable harm but measurable is one thing, perceptions are another.

So, for a lack any minimum standards and some overseas political involvement and the resulting negative perceptions, the product was withdrawn from the market (2013). Only now does it seem to be having a resurgence although in what seems to be a more ‘milder’ form judging by the reduced benefits it is able to achieve.

Angus’s article focused upon a potentially new breakthrough on preventing methane emissions from ruminant by inserting a bolus which would reduce the activity of methanogens in the rumen and the resulting expelling of methane.

Current management techniques of reducing methane emissions involve genetics, some animals just emit less and this can give gains of around 1.75% per year, good but patience required and grazing efficiencies, where if an animal is kept healthy and fed well it will achieve killable weights faster and therefore spend less time on the planet in the case of the finishing animal, produce more offspring or produce more milk and have less methane per kg/litre of product.

Potentially also if more efficient animals are carried then less are required to produce the same amount of product. This tends not to be the response of most farmers as they are trying to utilise all grass grown.

Grain-fed animals also have slightly lower methane emissions than grass-fed as it is a more concentrated feed.

Other issues come into play here about farming to our competitive advantages. All of these approaches do not impact upon the methanogens in the rumen. The other approaches which involve the animals ingesting ‘products’ be they seaweed or other yet to be seen products, reduce the outputs of the methanogens. My layman’s understanding of the impact of reducing methanogens has been it helps to improve the feed efficiency of the animal as energy, best described in a UC Davis article.

This early work revealed that 4–10% of the energy in livestock feed never even made it to a ruminant’s stomach. That portion of feed was basically wasted in the rumen, the part of the animal’s digestive system that comes right after the esophagus.

The rumen is essentially a gigantic fermentation vat where anaerobic microbes break down cellulose from plant cell walls, a process that forms propionate and other volatile fatty acids that serve as ruminants’ primary energy source. These microbes include archaea that combine hydrogen and CO2 - two by-​products of the rumen’s fermentation - to form the methane that flows from ruminants’ mouths. “It’s constant,” says Ermias Kebreab, a sustainable agriculture scientist at the University of California, Davis. “They’re burping all the time.”

By consuming hydrogen, the methanogenic archaea indirectly decrease production of propionate and, in turn, the production of milk and meat.

The article (as does Angus’s) provides quite a degree of optimism to the future with the “Scientific’ approach with up to 80% reductions being achieved in controlled settings.

Putting things into and on animals has been happening for generations and with the correct safeguards (like withholding periods etc.) and there has been no negative issues found. These interventions have targeted a range of organisms that can have often quite large negative impacts upon the animal’s health. These range from intestinal worms to fly-strike and even facial eczema, all which can have very nasty impacts upon animals. Some could argue that as with methane all these ills could be controlled without man made interventions i.e. by gene selection etc. However, done naturally these make quite slow progress and perceptions of GM selection mean that is not on the near radar for the moment.

So back to the methanogen interventions, I couldn’t find any information that covered whether reducing methane from the animals gut would have any negative effects upon the animal, although I can’t help wondering why evolution put the system in place in the first case if it ‘only’ creates inefficiencies to the digestive system.

Also if seaweeds and the like are what the intervention products are made from, then they are unlikely to be a source of future problems. However, going back to the DCD experience, developers need to make sure they leave no rocks unturned in searching for impacts, good and bad and then convey that to all. Nipping flawed perceptions in the bud, we have learnt over the last couple of years, is far more effective than trying to regain lost ground after flawed ideas (if they indeed are) have been spread.

And finally, here is a link to an Australian guide book for rural communities providing 30 tips for being a valued contributor; tips, tricks and advice for building strong country committees. It provides handy 101-level advice on how young people can contribute to show societies, rural boards, and agricultural committees in a new handbook available online. Not for everyone but may be useful.