Seaweed Might Help Cows Go Green

16:25 minutes

a cow laying down in a hay-filled page staring at the camera
This steer at UC Davis was fed a small amount of seaweed that resulted in a dramatic drop in methane emissions. Credit: Breanna Roque/UC Davis

When it comes to the bodies of humans and animals, there are a few functions that we’re usually discouraged from talking about. Specifically, the ones that involve releasing gas. (Yep, burps and farts.) But if you’re a cow, there’s a lot of scientific work that goes into analyzing what’s coming out in the gas you release. That’s because the cattle industry is one of the largest producers of methane gas, a huge contributor to global warming.

Some scientists are experimenting with feeding cows new things, to try to limit their methane output from the inside. New research shows a very promising result: By feeding beef cattle just a few ounces of dried seaweed per day, methane emissions from the cows went down as much as 82 percent.

Ira talks to the lead author of that paper, Ermias Kebreab, associate dean and professor of animal science at the University of California, Davis about how seaweed inhibits methane production in cows. They’re also joined by Albert Straus, founder and CEO of Straus Family Creamery in Marshall, California, who will be testing the seaweed diet on his cows this summer.

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Segment Guests

Albert Straus

Albert Straus is founder and CEO of the Straus Family Creamery in Marshall, California.

Ermias Kebreab

Ermias Kebreab is an associate dean and professor of Animal Science at the University of California, Davis in Davis, California.

Segment Transcript

IRA FLATOW: This is Science Friday. I’m Ira Flatow. When it comes to our bodies, there are a few bodily functions, well, let’s say that we’re usually discouraged from talking about, like releasing gas with a burp, or a gas that comes out of the other end, you know what I mean. But if you’re a cow, there’s a lot of scientific work that goes into analyzing what’s coming out in the gas you release. That’s because the cattle industry is one of the largest producers of methane gas, a huge contributor to global warming.

While some people are leaning away from beef, trying to limit their carbon footprint, the industry isn’t going away any time soon. So what if we could feed cows something that seriously decreases the amount of methane they release? Joining me today is a researcher who’s looking into this very question. Dr. Ermias Kebreab, Associate Dean and Professor of Animal Science at the University of California in Davis. Welcome to Science Friday.

ERMIAS KEBREAB: Thank you for having me, Ira.

IRA FLATOW: You’re welcome. Now, I know in your research, you’re feeding cattle something that they would never come across in nature, right?

ERMIAS KEBREAB: This particular seaweed, yes, you’re right. But cows actually and ruminants, sometimes, they do forage on seaweed, if they are close to a seashore.

IRA FLATOW: So seaweed you’re giving them as part of their main diet?

ERMIAS KEBREAB: Not really. We’re giving them very little amount of seaweed, so maybe between 1 to 3 ounces of seaweed added to their normal diet. So we will not change their diet at all. We just put a little bit of seaweed into that diet.

IRA FLATOW: And you found that putting seaweed in cows’ diets cuts methane emissions by how much?

ERMIAS KEBREAB: We found it to cut emissions up to 80% or even a little bit more than 80%.

IRA FLATOW: Wait a minute, I’m trying to absorb that. You’re putting a tiny bit of seaweed in their diet, but you’re cutting emissions by 80%?

ERMIAS KEBREAB: That’s exactly right. Yes, by putting a little bit of seaweed to their diet without changing the diet whatsoever, we have seen a reduction of methane emissions by up to 80%, and sometimes even more than that.

IRA FLATOW: And how do you explain that?

ERMIAS KEBREAB: The explanation is that the seaweed that we are using has active ingredients that would block or inhibit some of the enzymes that are required by the microbes in the gut of the animal. So the gas is actually being produced by the microbes in the gut of the animal, and those microbes require certain steps to make methane. So they make methane from hydrogen that’s released by other microbes when they are fermenting food and fiber.

And so the process takes them into this using a certain specific enzyme to convert hydrogen and carbon dioxide into methane. And what the seaweed is doing is that through these active ingredients, halogenistic compounds, it inhibits that last step of converting into methane, so it will not go into that last step. So what we will see is that hydrogen would be released instead of methane.

IRA FLATOW: Is there something about a cow’s digestive system that makes this happen?

ERMIAS KEBREAB: Yes, exactly. I mean the cow is a special animal and the animal that really utilizes things that we cannot eat, like grass and hay and all that. And the reason it does that is because it’s working with thousands of different type of microbes in its gut to help it break down particularly cellulose. And during that process is when all these gases are released, and other microbes have evolved to take advantage of that. The fact that there is a lot of hydrogen and carbon dioxide within the rumen, and so they use that, and they grow their cells, and the byproduct of that is they produce methane, as well.

IRA FLATOW: This is all so amazing. How long did it take to see this change in the methane emissions? Was it right away? Did it take some time?

ERMIAS KEBREAB: That’s the surprising part, is that, as soon as we put it in, within a day we could see that change. As soon as we put it in, the next day we measured the emissions. And we can see already quite a huge drop. So it works pretty quickly.

IRA FLATOW: Wow, the next day. And the study you were doing, the study is in beef cattle. Does adding seaweed in the cows’ diet change how, for example, they taste?

ERMIAS KEBREAB: Actually we did that work. We actually had about 112 people to taste the meat that was prepared from animals that were given the seaweed, and those that were not given the seaweed. And they could not detect any difference in terms of the taste, the juiciness, or anything like that. So we did this with people tasting the meat or steak.

But also we looked at proximate analysis, which is looking at what is in the meat. And so we did a scientific analysis of the components of the meat, and we did not see any significant difference as well.

IRA FLATOW: Interesting. So much for the academic study. I want to bring along someone who is a dairy farmer whose cows will enter a seaweed trial this summer, Albert Straus, founder and CEO of Straus Family Creamery in Marshall, California. Welcome to Science Friday.

ALBERT STRAUS: Thank you, Ira.

IRA FLATOW: Albert, why are you volunteering your cows for this experiment?

ALBERT STRAUS: So I have an organic dairy farm. We were the first certified organic dairy and creamery west of the Mississippi River, and first 100% certified organic creamery in the United States. Our mission is to sustain family farms by producing 100% high-quality organic food, dairy products, and help revitalize rural communities through education advocacy everywhere. So my goal is to have an economic viable farming model that is good for the planet, good for the environment, and, at the same time, producing high quality organic food for the local community.

So, when I heard that red seaweed was a potential solution to methane emissions from the cows, I was very excited. I gave a goal three years ago to my sustainability director to be carbon neutral on my farm by the end of 2021, and expand it to the other farms that supply us by the end of the decade, the other 11 farms. And it’s made up of four things. One is we have a methane digester. It takes the manure from the cows and captures the methane and makes all electricity for the farm. And we’re actually collaborating with BMW to take advantage of selling the carbon credits for that.

Second part is that we have the first dairy to have a carbon farm plan, which is using compost and using animals to graze. And it’s been shown that we can sequester carbon back into the soil from the atmosphere. It’s recognized internationally as one of the only ways to reverse climate change rather than reduce it. And then the third part was the red seaweed. Almost half of the methane that’s emitted by cows comes from their belches, not their farts.

And so that was the third part of my goal, is if we could feed this low amount of red seaweed to the cows, that would be a very exciting part of it. And then the fourth thing is to where we’ve converted our vehicles on the farm to be electric. Our truck to feed the cows is electric and is powered by the cows that it feeds.

So this fit very nicely into that model. And we’ve been collaborating with Ermias and his team. And we want to be the first commercial trial in the United States for this.

IRA FLATOW: So you want to be a pioneer in sustainable farming. I mean, seems like you’re already on that pathway.

ALBERT STRAUS: Yeah. We’ve tried to create a model of farming that’s sustainable economically, environmentally, and produce a high quality of food in a local and regional model that other communities can replicate throughout the United States and throughout the world.

IRA FLATOW: Have you fed your cows interesting things like this before?

ALBERT STRAUS: I’ve fed all kinds of interesting things over the years. I have tried tofu waste livestock feed that’s organic. Sake waste, cocoa bean hulls, I’ve done a lot of different things, because for dairy cows most of the feed is, as bad a reputation as they have, they take a lot of the waste products and convert it into milk, into protein. And so, well, the interesting thing is, for organic cows, they have to feed on pasture as much as they can and get most of their feed from pasture, during the growing season.

But by feeding this forage, they’re actually producing more methane, because the bacteria that digest the grasses also give out methane.

IRA FLATOW: Seaweed’s quite slimy and stringy. I guess you’re not plopping seaweed into their bowls. You’re turning the seaweed first into little pellets and then feeding it to your cows, basically.

ALBERT STRAUS: Yeah, I think it’s freeze dried, and so it’s a powder that will mix into their feed.

IRA FLATOW: Do you know where the source of your seaweed comes from? Does it come from, say, kelp beds in California or other seaweed beds in California?

ALBERT STRAUS: No, I think it’s subtropical. And I think this initial batch came from the Azores. They are trying to grow it in Southern California as well as Hawaii. So I think they’re trying to create a commercialization of the seaweed, so we can expand it rapidly.

IRA FLATOW: Ermias, is there more research that has to be done to make better seaweed, or you’re pretty happy with the product that you’ve got now?

ERMIAS KEBREAB: Oh, no. There is actually some research that’s going on right now at the University of California, San Diego, where they’re looking at what type of seaweed, or sort of the variety of seaweed, and the potential to make even better quality of the active ingredients, could then be grown and can be used as well. So there is a lot of research that’s going on to try to make sure that we get the right amount of seaweed. So one thing that we have to remember is that, when feeding seaweed, we try to give them as little as possible. Too much seaweed, the palatability might be compromised.

So to try to make sure that we’re giving them as little as possible, so they don’t even notice that it is there, then we need to find a better quality of seaweed. So that work is going on right now. And hopefully we will find seaweed that is potent enough, so that when we give it to the cows and steers, it will be one or two ounces or even less than that.

IRA FLATOW: One or two ounces, Albert, that’s like you don’t even know it’s there, I guess, when you’re feeding a cow.

ALBERT STRAUS: Right. We feed a vitamin-mineral supplement to the cows. So this would replace part of that supplement. And so it’s a very little part of their feed. But it’ll be blended in with the rest of the feed, so it’s evenly dispersed throughout their feed that they eat every day.

IRA FLATOW: Are there other farmers, who you know, who are watching what you’re doing and waiting to see the results?

ALBERT STRAUS: My farm has kind of been the trial spot to prove organic farming. People thought I was crazy when I went organic. But now 85% of the dairies in our two counties are certified organic. I have a methane digester that was one of the first ones in California.

So a lot of these trials that I do are to prove to other farmers that it’s a viable solution to a problem. I know the farmers want to do a good job and want to be in a positive light and create a healthy food for the community.

IRA FLATOW: This is Science Friday from WNYC Studios, talking to Dr. Ermias Kebreab, Associate Dean and Professor of Animal Science at the University of California in Davis, Albert Straus, founder and CEO of the Straus Family Creamery in Marshall, California. I know you’re a farmer who clearly, clearly cares a lot about sustainability and being a good steward of the land. I know that listening to you now.

But what do you think it will take for other cattle and dairy farmers to take action on the methane emissions of their cows? I mean, I imagine there is an economic, right, a large economic question here, can I make money doing this? And what’s the answer to that?

ALBERT STRAUS: I think that California, as well as nationally and internationally, we’re addressing climate change and really trying to make a solution. In California, we have a law to reduce our methane emissions by 40% by 2030. And part of the solution is the dairy industry and the livestock industry. So there’s a kind of a carrot and a stick. I think we’re trying to show that you can economically feed this. It won’t have any detrimental effect.

Hopefully it will have only a positive effect, and that other farms, by adding it into their feed rations, that it will be a positive solution. And so I think as we work collaboratively to address climate change, this is really one of the main solutions that we have, and really can highlight agriculture as being a positive part of our society, and a needed part of our society.

ERMIAS KEBREAB: That there are two ways in which farmers can make money out of this. One is what we saw, was that there was an improvement in efficiency. There was about a 20% improvement in efficiency, which means that you would need less amount of money to get the same gain. And so that would basically reduce the cost of the farmer to feed the animals. And the second way, what Albert alluded to, is to claim carbon credit.

And one of the things that we are doing actually now, with the help of the California Dairy Research Foundation, is to come up with a protocol. So you need to have a protocol to be able to show that, when you reduce carbon, how much carbon you’re reducing in what you’re doing, and all that needs a protocol. And that’s what we’re doing right now to try to develop this protocol, so that farmers can take credit, not just with seaweed but any type of mitigation that reduces methane emissions, enteric methane emissions, they can take advantage of that.

IRA FLATOW: Is there another additive, I’m going to call it, besides seaweed, that you’re looking at?

ERMIAS KEBREAB: Oh, yeah. So we are looking at several different types of feed additives. We’ve looked at an additive called Mootral that reduces emissions by about 23% or so. We’ve looked at a new additive that we just finished. So I don’t have the results yet, but we just finished looking at a new additive. And we’ve done an analysis of an additive that a lot of experiments have been conducted. And we’ve seen the 3NLP, or it’s called Bovaer, reduces methane emissions by up to 30% as well.

IRA FLATOW: Albert, are you going to be able to see an 80% reduction in methane? Are you able to measure it in your cows when you feed them the seaweed?

ALBERT STRAUS: So the trial that we will be doing this summer will have a measuring device that measures the belches from the cows and it analyzes it. So we’ll be able to get that data.

IRA FLATOW: And when will you begin giving your cattle seaweed?

ALBERT STRAUS: We’re hoping to do it after the pasture season in July or August this year.

IRA FLATOW: Well, maybe we’ll check back with you, see how it’s going.

ALBERT STRAUS: That’d be terrific.

IRA FLATOW: Thank you both, gentlemen, for taking time to talk with us. I wish both of you good luck, because this is the kind of thing that we’d love to hear about, where you are able to come up with new ideas and hopefully make global climate change something we can live with. Dr. Ermias Kebreab is Associate Dean and Professor of Animal Science, University of California in Davis, Albert Straus, founder and CEO of Straus Family Creamery in Marshall, California, thanks again. Thank you both for joining us today.

ERMIAS KEBREAB: Thank you for having us.

ALBERT STRAUS: Thank you, Ira.

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