Can California dairy farms become carbon neutral?

Can California dairy farms become carbon neutral?

There are several different greenhouse gases that contribute to increasing the Earth’s temperature. Carbon dioxide is mentioned most often in conversations about climate change because of how much we emit and how long it stays in the atmosphere. Methane comes second. Its atmospheric lifetime ranges from 10 to 20 years, much shorter than the lifetime of several thousand years of carbon dioxide. But when it comes to warming, methane gas is 50 to 80 times more potent than carbon dioxide. For this reason, scientists are looking for ways to limit the amount of methane we release. There are many sources of methane, some of which are natural such as when biomass decomposes in humid regions of the world. Others are man-made in places like oil refineries that often inject methane into the production of fossil fuels. Some are somehow a mixture of nature and humans. For example, cows. According to the USDA, there are over 9 million dairy cows in the United States. Each cow can produce, on average, 220 pounds of methane gas each year. This represents more than 25% of the country’s methane emissions. But it’s not the fault of the cows. They are known as ‘ruminants’, which means they have a complex four-chambered stomach. “The first stomach chamber they have is called the rumen,” said Dr. Frank Mitloehner, a scientist in the UC Davis Department of Animal Science. This rumen can expand to contain the volume of a standard bathtub. In the rumen, microbes help break down what cows eat. And their diet is quite harsh. This includes things like almond husks, straw, and cotton plant residues. The decomposition process releases methane as a byproduct. The cows then spit this methane and release it into the air. “Contrary to common belief, it doesn’t come out the back, it comes out the front,” Mitloehner said with a smile. However, manure is also a source of methane. The one that Californian farmers are trying to fill, literally, by covering their lagoons with manure. This trapped gas can then be turned into transportation fuel. But back to belching. The dairy herd housed at UC Davis works hard to reduce emissions. And all they have to do is eat. Mitloehner and his team tested different food additives that were shown to significantly reduce enteric or belched methane. These additives are often natural, being composed of different essential oils or algae. It only takes a little to be effective. An average adult dairy cow can eat 100 pounds of feed per day. But only one gram of additive is used and that little bit goes a long way. “On the dairy side, we saw reductions of about 10% in methane,” Mitloehner said. Other additives can reduce methane emissions by up to 50%. These additives work either by alerting the microbiome in the intestines of cows or by inhibiting methane as a byproduct of digestion. These reductions are measured using special power stations called head chambers. Cows eat, drink, digest and hang out in these head chambers during test cycles. As they belch, sensors attached to the head chambers measure methane concentrations. Mitloehner said it takes a bit of practice to get cows used to head chambers, but ultimately they aren’t stressed by their working environment. “They can see their peers. They can eat there, they can drink there and breathe normally,” Mitloehner said. The cows don’t know it, but their work is paying off. methane emissions by 25% Mitloehner said the technology exists to eventually help dairy farms become carbon negative, meaning they will actually help remove carbon from the air rather than create more. .a climate solution and the dairy and beef sectors can be part of it,” said Mitloehner. Feed additives are already widely used with cattle in Europe. Although not banned in the United States, it is not also not approved by the FDA as a method of reducing methane. Mitloehner said that would be the next big step in seeing these additives become more popular. “I think we should push to play that role because these reductions are s meaningful, they’re immediate, and they can really help us get the job done,” Mitloehner said.

There are several different greenhouse gases that contribute to increasing the Earth’s temperature. Carbon dioxide is mentioned most often in conversations about climate change because of how much we emit and how long it stays in the atmosphere.

Methane comes second. Its atmospheric lifetime ranges from 10 to 20 years, much shorter than the lifetime of several thousand years of carbon dioxide.

But when it comes to warming, methane gas is 50 to 80 times more potent than carbon dioxide. For this reason, scientists are looking for ways to limit the amount of methane we release.

There are many sources of methane, some of which are natural such as when biomass decomposes in humid regions of the world. Others are man-made in places like oil refineries that often inject methane into the production of fossil fuels.

Some are somehow a mixture of nature and humans. For example, cows.

According to the USDA, there are over 9 million dairy cows in the United States. Each cow can produce, on average, 220 pounds of methane gas each year. This represents more than 25% of the country’s methane emissions.

But it’s not the fault of the cows. They are known as ‘ruminants’, which means they have a complex four-chambered stomach.

“The first stomach chamber they have is called the rumen,” said Dr. Frank Mitloehner, a scientist in the UC Davis Department of Animal Science.

This rumen can expand to contain the volume of a standard bathtub. In the rumen, microbes help break down what cows eat.

And their diet is quite harsh. This includes things like almond husks, straw, and cotton plant residues. The decomposition process releases methane as a byproduct.

The cows then spit this methane and release it into the air.

“Contrary to popular belief, it’s not coming from the back, it’s coming from the front,” Mitloehner said with a smile.

However, manure is also a source of methane. The one that Californian farmers are trying to fill, literally, by covering their lagoons with manure. This trapped gas can then be turned into transportation fuel.

But back to belching.

The dairy herd housed at UC Davis works hard to reduce emissions. And all they have to do is eat.

Mitloehner and his team tested different food additives that were shown to significantly reduce enteric or belched methane. These additives are often natural, being composed of different essential oils or algae.

It only takes a little to be effective. An average adult dairy cow can eat 100 pounds of feed per day. But only one gram of additive is used and that little bit goes a long way.

“On the dairy side, we’ve seen reductions of around 10% in methane,” Mitloehner said.

Other additives can reduce methane emissions by up to 50%. These additives work either by alerting the microbiome in the intestines of cows or by inhibiting methane as a byproduct of digestion.

These reductions are measured using special power stations called head chambers. Cows eat, drink, digest and hang out in these head chambers during test cycles. As they belch, sensors attached to the head chambers measure methane concentrations.

Mitloehner said it takes a bit of training to get cows used to head chambers, but ultimately they aren’t stressed by their working environment.

“They can see their peers. They can eat there, they can drink there and breathe normally,” Mitloehner said.

The cows don’t know it, but their work is paying off. So far, California has already reduced its methane emissions by 25%.

Mitloehner said the technology exists to eventually help dairy farms become carbon negative, meaning they will actually help remove carbon from the air rather than create more.

“And that’s what really excites me. That a big reduction in methane can be part of a climate solution and the dairy and beef sectors can be part of that,” Mitloehner said.

Feed additives are already widely used in cattle in Europe. Although not banned in the United States, it is also not approved by the FDA as a method of reducing methane. Mitloehner said that would be the next big step in seeing these additives become more popular.

“I think we should encourage [dairy farmers] play that role because those reductions are significant, they’re immediate, and they can really help us get the job done,” Mitloehner said.

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