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Oct 08, 2023

Colorado scientists delve into cattle intestines to cut greenhouse gas emissions

In many ways, the research pens at Colorado State University (CSU) are what you’d find on your standard cattle feedlot. There are cows, of course, plenty of mud, and the inevitable, nostril-turning stench of livestock.

But this feedlot at CSU's agricultural research and education center in Fort Collins doubles as a scientific laboratory. It's where researchers in the AgNext program - a specialized research group for sustainability in animal agriculture - are learning about the greenhouse gases cows produce as they stand around digesting food. The feedlot is tricked out with millions of dollars of equipment that allow scientists to track everything that goes into each cow, along with some of what comes out.

Specialized feed bins use radio-frequency identification (RFID) technology to track every ounce of corn consumed on a per cow basis. Another piece of equipment called the GreenFeed machine analyzes the gases cattle exhale. It's a bit like a high-tech gumball machine, dispensing tasty cow treats – alfalfa pellets – on a schedule, and at the beckoning of a smartphone app operated by researchers.

On a chilly afternoon in March, Colorado State University Animal Sciences Professor Sara Place demonstrated the technology, tapping a button on her phone. A high-pitched electronic chime sounded and the alfalfa pellets dropped into an opening at cow level, catching the attention of a big-eyed angus who moseyed up for a bite to eat.

"He's got his head stuck in the machine and he's chowing down a little bit of a snack," Place explained.

Despite common misconceptions about the perils of bovine flatulence, most methane comes out of the cow's front end in the form of enteric emissions. That means each time a cow gets a snack from the GreenFeed machine, Place has an opportunity to get information.

"The air gets pulled from around the animal's face, and whatever they're respiring out goes directly into the machine," Place said. "We can get real time methane emissions data from that."

Methane is a powerful greenhouse gas that has a warming power 80 times more potent than carbon dioxide in the first 20 years of emission. The animal agriculture industry, which includes all operations that raise animals for meat or dairy, produces more methane than any other human activity in the U.S.

Climate experts say we’re running out of time to prevent climate catastrophe. To avoid the worst of it, experts say it is imperative to cut greenhouse gas emissions dramatically before 2030. Environmental groups have ambitious goals to reduce agricultural methane emissions by 30 percent globally by the year 2030.

But when it comes to emissions from the livestock sector, the science is still just emerging, and it's not yet clear if the cuts will come in time—or how.

Place hopes to change that with her work in the research pens.

"We want to find solutions that can help mitigate those emissions to cut the climate impact of beef," Place said.

A tricky proposition

Reducing the climate footprint of beef is a complex problem. According to Kim Stackhouse Lawson, director of CSU's AgNext program, producing methane is just part of being a cow.

"They're biologically supposed to make methane," she said.

The gases are the byproduct of a complex fermentation process that happens inside a cow's largest stomach, called the rumen. Changing that equation involves tinkering with the complex microbiological ecosystem inside a living animal's stomach, which means there's still a lot we don't know.

For instance, there is still no experimental data on baseline emissions from the livestock industry.

"The data is not granular enough," Stackhouse Lawson said.

The best understanding of the cattle emissions picture comes from the Environmental Protection Agency's greenhouse gas emissions inventory, which derives its data from a model that uses emissions factors - essentially multipliers from a chart, so the data is based on equations rather than direct measurements from the animals themselves.

Stackhouse Lawson said the inventory does a decent job of estimating livestock emissions at the scale of the entire U.S. But for individual operations trying to account for the carbon footprint of their own herds, those numbers are too generalized to tell the full story.

"There's too much variability between animals, there's too much variability within region," she said.

Stackhouse Lawson's team is only now doing the work of developing more precise numbers. She cited surprising initial data from CSU's research pens that shows the quantities of methane cows produce can vary wildly from animal to animal, suggesting an entirely new frontier for the research.

"Is there a genetic component?" She wondered. "Would we select animals that have lower methane?"

The CSU team is also looking at other variables like feed additives that can cut emissions outright.

John Tauzel, senior director for global agriculture methane with the Environmental Defense Fund, explained successful additives "will change the biome of the cow's stomach to reduce the amount of methanogens—the organisms that create the methane." It's a solution he went on to describe as "really, really complex," because of the complicated structure of the livestock industry and the biological intricacies of cattle microbiomes.

That complex problem remains only partially solved, in part due to a lack of funding for the research. Tauzel pointed out that only 2 percent of federal funds that support research and development for climate adaptation and mitigation in agriculture go toward reducing enteric emissions.

"We need more investment in that space if we're going to meet the reductions in timeframes that we need," Tauzel said.

That investment is starting to come. Just last week, the team at AgNext announced it had received a $1 million Conservation Innovation grant from the US Department of Agriculture. The money will support continued research into emissions on the feedlot. It will also allow the researchers to expand their inquiry into cattle emissions to look at cows grazing in a pasture setting.

Stackhouse Lawson hopes more funding could be part of the next Farm Bill currently being negotiated in Congress.

Until more federal dollars start flowing, the research being done on cattle emissions is dependent on industry to fill the funding gap.

Industry's stake in reducing emissions

Five Rivers Cattle Feeding bills itself as the world's biggest cattle feeding operation. The Northern Colorado-based company runs 13 feedlots across six western states, with the capacity to fatten up to 900,000 head of cattle at any given time. A cow typically spends about six months on one of Five Rivers’ feedlots, during which time it can put on anywhere between 500 and 700 pounds.

"What we're all about is efficiency," said Vice President of Environmental Affairs and Sustainability Tom McDonald. "[We’re] getting cattle to perform at their best while they're at the feedlot."

Part of that commitment to cattle performance includes support for the ongoing work at CSU's research pens.

"The whole goal here is to learn what our greenhouse gas footprint is, and then how can we improve it?" McDonald said.

All of the emissions research animals at CSU are on loan from Five Rivers. The company also supplies the animals’ feed and has donated $600,000 worth of equipment to the cause, including the GreenFeed machines that collect and analyze cow exhalations.

McDonald said his company expects to recoup that sizeable investment and then some in the eventual efficiency gains made possible by the research.

Methane, after all, isn't just a greenhouse gas. "Methane is energy," McDonald said. "When energy is lost, that's a wasted resource."

CSU researcher Sarah Place said reducing methane emissions from cows could actually mean more beef to go around.

"[Methane] is basically feed calories the animal eats that actually get lost to the atmosphere," Place explained. That means the less methane a cow exhales as it digests, the more weight it puts on that ultimately becomes beef. In other words, a lower emitting cow is more efficient at converting corn feed to body mass than a higher emitting cow.

McDonald likened the company's interest in lowering cows’ methane emissions to any other sound business decision.

"When we upgrade equipment at the feed mill, we look for energy efficient equipment. We strive to reduce our energy usage in those areas," he said. "From a cattle performance standpoint, we utilize the tools available to help the cattle grow faster, gain faster."

A race against the climate time horizon

But for all the enthusiasm from the agriculture industry, the work at AgNext and a handful of related research facilities around the country is still young. Scientists are working to translate promising treatments from the pristine laboratory setting to actual, scalable applications in the feedlot.

"We've got a lot of exciting research that is underway," Stackhouse Lawson said. "But it's not ready yet."

That's a problem, according to Ben Lilliston, director of climate and rural strategies at the Institute for Agriculture and Trade Policy, a climate and agriculture think tank.

"[The technologies] are not proven yet," Lilliston said. "We need to have emissions reductions really quickly, like in the next seven years. Speculative technologies are… You know, it's not to say that they're not worth exploring, but [I] wouldn't rely on them as a real climate mitigation strategy."

Apart from the scarcity of feedlot-ready solutions, Lilliston points to factory farming itself – an industrial system hell-bent on continual growth - as the main culprit.

"Even if you're able to reduce emissions a small amount by some of these scientific advances, if you're going to continue to grow and expand the number of animals that are part of that system, then you're going to negate those gains," he said.

He thinks of the emerging technologies as a distraction from the bigger question that we’re not asking: how many beef and dairy cows do we need in this country? After all, a more immediate solution to the livestock methane conundrum is to have fewer cows.

"Reducing the cattle herd is the clearest way to reduce actual emissions," Lilliston said.

Of course, a smaller cattle herd would mean less meat and dairy on the market, which would impact consumers’ meal choices. It's a situation John Tauzel doesn't find feasible.

"For various reasons, whether that's social, whether that's economic, livestock products are going to continue to be part of a significant portion of the global diet for the foreseeable future," Tauzel said.

That's why he believes advancing research on livestock methane emissions is critical.

"If people choose to eat a hamburger, we want to make sure that when they eat that hamburger, it has the lowest methane footprint possible," Tauzel said.

As for Place, she wants to find solutions that simultaneously work for consumers, cattlemen and the climate.

"At the end of the day, we want to make sure we create practical solutions that can be adopted in the real world," Place said.

After all, people like their burgers. It just might be easier to alter the microbiome of an animal's gut than it is to change the cravings of a hungry planet. Copyright 2023 KUNC. To see more, visit KUNC.

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