Tuesday, October 26, 2021

Gas giants: Can we stop cows from emitting so much methane?

Myriam LEMETAYER
Tue, 26 October 2021

Gas giants: Can we stop cows from emitting so much methane?
 (AFP/Lou BENOIST)

That cow may look peaceful and harmless, munching on some grass in a verdant pasture.

But don't be fooled -- it is emitting methane, a particularly potent greenhouse gas contributing to runaway global climate change.

Agriculture is responsible for 12 percent of global man-made greenhouse gas emissions, much of it due to methane, the second most warming gas after carbon dioxide.


Methane is around 25 times more potent than carbon dioxide as a greenhouse gas over a 100-year period, but it stays in the atmosphere for only 12 years compared to centuries.

So drastically reducing methane emissions could have a major impact in mitigating the damage expected from global warming in the coming decades.

Agriculture and livestock farming generate around 40 percent of the methane related to human activities, the rest produced by the fossil fuel industry.

Much of that methane is produced by the digestive process in cows, which then burp the emissions out into the world.

Around 95 percent of the methane produced by cows come from their mouths or nostrils.

So how can we reduce the danger being belched out by cows across the world every day?



Who, me?: New tactics are being investigated to try to curb the methane emissions of cows

- Cows with masks -

US agricultural giant Cargill, partnering with British start-up ZELP (Zero Emissions Livestock Project), has developed a form of mask that covers cows' nostrils.

The device filters the methane, transforming it into carbon dioxide, which per molecule has a much less potent effect on global warming.

Ghislain Boucher, head of the ruminant team at Cargill's animal nutrition subsidiary Provimi, said the first results were "interesting".

"Methane emissions have been reduced by half," he told AFP.

However the device still needs to be tested in real-world conditions before it can be marketed late next year -- or even in 2023.

In the short term, Cargill is starting to market in northern Europe a calcium nitrate food additive, saying that 200 grammes daily would reduce cow methane emissions by 10 percent.

The additional cost is estimated to be "between 10 and 15 cents per cow per day," Boucher said at a breeding gathering in central France.


- Seaweed to the rescue? -


Adding red seaweed to cow feed has far more potential, according to a US study published earlier this year, which indicated it could reduce methane emissions by more than 80 percent.

If the results can be repeated, red seaweed would need to grown in vast quantities, preferably near farming areas, the researchers at University of California Davis said.

However a question looms over the issue: how will farmers react to paying more for such measures which do not add to their bottom line, unless they are reimbursed via some kind of carbon credit?

It is also uncertain how consumers will respond. For example, will Americans who prefer corn-fed beef be as partial to the seaweed-fed variety?

And perhaps the easiest way to reduce cow methane emissions is for the world to eat less beef and diary.

A report by the United Nations Environment Programme in May pointed out that technological measures have a "limited potential to address" methane emissions from the agriculture sector.

"Three behavioural changes, reducing food waste and loss, improving livestock management, and the adoption of healthy diets (vegetarian or with a lower meat and dairy content) could reduce methane emissions by 65-80 million tonnes a year over the next few decades," it said.

myl/ico/dl/rl

Orkney's seaweed-eating sheep offer hopes of greener farming

Issued on: 27/10/2021 -

The ultra-remote island of North Ronaldsay may boast only around 60 people -- but it is home to what scientists say could be a breakthrough in cutting planet-warming methane emissions -- seaweed for its distinctive sheep Adrian DENNIS AFP


North Ronaldsay (Orkney) (Royaume-Uni) (AFP)

On a tiny island in Scotland's far-flung Orkneys, thousands of sheep spend the winter munching on seaweed, a unique diet that scientists say offers hope for reducing planet-warming methane emissions.

Around 60 people share North Ronaldsay -- an island just over 3 miles (5 kilometres) long, ringed by rocky beaches and turquoise waters off the north coast of mainland Britain -- with the distinctive native sheep.

Boasting brown, beige or black wool, the animals are hemmed into its foreshore owing to a large system of stone walls -- called a sheep dyke -- built in the early 19th century to keep them away from fields and roads.

The island's crofters -- people who live and work on so-called croft agricultural land -- wanted to use every available space to grow crops and as pasture for cows.

The unintended result: in summer the sheep can nibble on grass, but by winter eating the plentiful seaweed is their only means of survival.

While some other mammals -- including Shetland ponies native to the neighbouring island chain, and red deer -- are known to snack on seaweed, scientists say that the North Ronaldsay sheep are unique worldwide for spending months eating only the marine plants.

Methane reduction

With the world facing a deepening climate emergency, they are increasingly seen by some as a case study that could lead to a breakthrough in methods for raising livestock, which is a major source of greenhouse gases.

Farm animals belch and fart methane gas which, though trivial sounding, is about 30 times more powerful than carbon dioxide at trapping heat in the atmosphere.

Given the vast scale of the global meat industry, the issue has become a major focus for climate scientists -- just as world leaders prepare to gather in the Scottish city Glasgow from Sunday for the crucial COP26 summit.

The seaweed diet of the Orkney sheep has an effect on their complex digestive system and appears to reduce the amount of methane produced.

"There's different components in the seaweed that actually interfere with the process (of) how methane is made," said Gordon McDougall, a researcher at The James Hutton Institute in Dundee in eastern Scotland who has been examining the sheep's diet for two decades.

Researchers at The University of California, Davis, published results in March showing that a "bit of seaweed in cattle feed could reduce methane emissions from beef cattle as much as 82 percent".

David Beattie, another James Hutton Institute scientist, stressed there is huge interest in such innovation.

"There's a really big movement within the industry to try and cut out the carbon footprint that the industry as a whole has," he told AFP.

"I see seaweed playing a part in that."

Scale


This would not necessarily mean cows and sheep switching to a diet entirely comprised of seaweed like the North Ronaldsay sheep, but it could supplement their usual feed.

Seaweed is not available in large enough quantities to feed so many animals, McDougall noted, and taking away too much from the sea could also damage the environment and ecosystems.

But the marine plants -- good sources of minerals, vitamins and omega-3 fatty acids -- could partly replace soy, which is heavily used in animal feed but transported for thousands of miles and linked to deforestation.

Researchers still need to determine the types and quantities of seaweed which could be best suited to adding to feed.

"And then, can you scale that up to a level where you'd actually have an effect on the overall UK farming?" said McDougall.

The plump North Ronaldsay sheep, who chow down strands of seaweed as if they were spaghetti, are set to keep providing a useful case study.

© 2021 AFP

Kiwi boffins aim to clear the air on livestock emissions





Tucked away in rural New Zealand, a multi-million dollar research facility is working to slash the greenhouse gases released into the atmosphere by farm animals -- saving the world one belch at a time (AFP/Marty MELVILLE)

Neil SANDS
Tue, October 26, 2021

Tucked away in rural New Zealand, a multi-million dollar research facility is working to slash the greenhouse gases released into the atmosphere by farm animals -- saving the world one belch at a time.

Cattle and sheep are kept in perspex pens for two days per session as scientists carefully analyse every burp and fart that emerges from them at the New Zealand Agricultural Greenhouse Gas Research Centre.

"I never thought I'd make my living measuring the gas that comes out of animals' breath," the facility's director Harry Clark told AFP.


The UN says agricultural livestock accounts for 14.5 percent of all greenhouse gas emissions generated by human activity and the centre -- regarded as a world leader in livestock emissions research -- is hopeful it can play a key role in tackling the problem.

How authorities ended up funding the project to the tune of NZ$10 million (US$7.0 million) a year is a story of economic necessity and changing attitudes to climate change.

But it begins in the gut of ruminant livestock, which use microbes to partially digest their food by fermenting it in a compartment of their stomach before regurgitating it to be chewed as cud.

The process results in copious amounts of methane -- a gas that has more than 80 times the 'global warming potential' of carbon dioxide, across 20 years according to the UN Economic Commission.

There are estimated to be 1.5 billion cows on the planet, with each one capable of producing 500 litres (132 gallons) of the gas each day.

In addition, livestock urine produces nitrous oxide, another powerful climate pollutant.

- 'Tantalising' methane vaccine' -

New Zealand's farm-reliant economy means its proportion of agricultural emissions is much higher, accounting for around half of its greenhouse gases.

At Clark's centre in Palmerston North, the major focus is on livestock methane, which accounts for almost 36 percent of the country's total.

"New Zealand has a specific problem and it's imperative we give farmers the tools and technologies to reduce their emissions," Clark said.

The facility, which is vetted by an ethics committee, is exploring research that includes selective breeding programmes to develop bloodlines of animals that naturally produce less gas.

Sheep have been bred that produce 10 percent less methane than average and Clark said researchers were trying to produce similar results with cattle.

Other projects include putting emission-inhibiting additives in livestock feed and even developing a harness or mask with filters that capture methane before it leaves the animal's mouth.

But Clark said perhaps the most exciting prospect being developed in Palmerston North is a vaccine that reduces methane by targeting the microbes in the gut that produce the gas.

"It's tantalisingly close, in the sense that it works in the laboratory but it doesn't work in the animal yet," he said, adding such a vaccine could be easily administered to flocks and herds worldwide, with an immediate impact on global emissions.

It is a growing area of research globally: In the US, researchers are experimenting with probiotics for cattle, while in India, scientists are adding supplements to feed -- with the aim of reducing the amount of methane produced.

But critics warn this approach offers only short term benefits and "band-aid" solutions to major problems.

"Reducing methane output while breeding still more methane-producing animals ignores animal suffering, deforestation, and the increased risk of diseases -- including zoonotic viruses -- all associated with animal agriculture," said Aleesha Naxakis, spokesperson for People for the Ethical Treatment of Animals (PETA).

- Global shift -


New Zealand’s government has committed to reducing livestock methane 10 percent by 2030 and 24-47 percent by 2050, compared with 2017 levels.

But some have questioned why the lucrative agricultural sector is treated differently to the rest of the economy, which has been set a target of zero net emissions by 2050.

Monitoring website Climate Action Tracker rates New Zealand’s climate policies as "highly insufficient", citing the methane carve out as one of the main reasons.

"As we look toward COP26, unless governments take immediate steps to transition our global food system away from animals and towards plants, we’re setting fire to the only home we have," warned Naxakis.

Clark conceded 'getting rid of livestock, and eating more plant-based foods' would reduce agricultural emissions and make both people and the planet healthier, but said the situation was more complex.

He said pursuing such a major shift, rather than working to lower livestock emissions, would have significant economic and social consequences on the sector worldwide.

Clark added that the government's funding of research into livestock emissions was only partly to do with New Zealand's reliance on the sector.

"Sure there's an element of self interest, but there's a bit of altruism there as well," he said.

"If we can find solutions that are applicable elsewhere, that help tackle emissions in China, the US, or wherever, then New Zealand could make a major contribution, as a small nation, to the global effort to reduce emissions."

ns/hr/lto




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