How Seaweed Could Slow Down Climate Change

We are hooked on meat. We chop, slice, and sink our teeth into it, it’s rooted in our genes and culture, and globally speaking, appetites are on the rise. The average amount of meat consumed per person has nearly doubled in the past 50 years. And this demand is putting an incredible amount of pressure on the world’s resources. Is there a way to feed everyone and help the
planet at the same time? Scientists think they might have found something in a new supplement plucked from the ocean. Here at UC Davis’s Beef Barn, a team of
scientists and students are mixing together molasses and a special kind of seaweed. They’ll sprinkle it over the cow’s meals, like a nutritional boost. We’re using for low dose about a quarter of
a percent. In our high dose is half a percent. It may not seem like much, but this dash of
seaweed is part of a new diet that could help curb greenhouse gas emissions in cows. Livestock are responsible for about 14 and
a half percent of the greenhouse gas emissions. And cattle are far and away the biggest contributors. Usually when you hear about methane from cattle
you think about cow farts and it’s actually the complete opposite. Methane from cattle mostly comes from the burps. But methane does not stay too long in the atmosphere, it actually gets destroyed in about ten to twelve years. However, it does have a global warming potential and traps heat within our atmosphere at about 28 times greater than carbon dioxide. But the world’s 1.5 billion cows really
can’t help themselves, it’s in their biology. A majority of the methane that comes from the animal itself is actually through enteric fermentation. There’s microbial populations within their
stomach and these microbial populations are actually degrading the feed and producing byproducts that the cows either absorb into nutrients, or other microbes actually ingest them and create other byproducts. Methane is one of these byproducts. Greenhouse gas emissions are very much related
to the quality of diet, the more forage, the more fiber, you get proportionately more methane emissions. And that’s why this seaweed, Asparagopsis, is so intriguing to an international community of scientists. It was first found in Australia. Some of this Asparagopsis was introduced into a Petri dish with the bacteria from the cow guts. They could actually prevent methane from being
produced. It struck me that this is something that could
also work quite well in real animals. Asparagopsis has an active ingredient called
bromoform. It basically acts as an inhibitor to an enzyme that’s required by the microbes to convert hydrogen into methane. It disrupts that process so that methane is not formed. Once the cows finish their dinner, the team will calculate their emissions to see if the seaweed is doing the trick. We use a machine called green feed. When an animal walks in it reads their ear
tag, it drops down feed, and they get to stay there and eat feed. Usually they barrel in there, but these young
steers were a bit camera shy. The machine will take their sample of the
breath and will then automatically analyze it. You can actually monitor it in real time. And their first study with dairy cows netted
some promising results. What we saw was a reduction of up to
60 percent when we feed 1 percent of seaweed to the cows. What we’ve seen so far is the amount of methane
that can be reduced is proportional to the amount of bromoform that the seaweed contains. This second study with beef steers will be
looking into the overall health of the animal. These animals will be eating seaweed for approximately 200 days. We’ll be able to capture that, if there’s any long term benefits to feeding seaweed. If it increases any weight gain, we’ll be able to see that as well. And another big question on everyone’s mind: we will have taste panels. They will tell us if they can pick up differences in meat quality from steers that have been fed seaweed and those that were not fed seaweed. So while they’re trying to understand how Asparagopsis will affect cow health and wellbeing, we’re trying to understand how to influence Asparagopsis’ health and wellbeing. Dr. Jennifer Smith is a marine biologist at
UC San Diego Scripps Institution of Oceanography. She’s working with the UC Davis team to
see how we can cultivate seaweed responsibly, so this potential solution doesn’t
become a whole new problem. Asparagopsis taxiformis is incredibly beautiful red seaweed. It produces a lot of really unique chemical
compounds, and some of these chemical compounds have been found to be really valuable. Just because we find that it could, potentially,
mitigate methane production in cows doesn’t mean that tomorrow we’re ready to mass produce Asparagopsis. I knew, given the complexity of this seaweed’s life cycle, that it was gonna take a bit of research. When you look at Asparagopsis growing in the wild, you often see these large, pink, feathery, iridescent, beautiful plants, and that is
one of the stages of Asparagopsis that eventually grow into another phase, and that phase looks a little bit like a pink cotton ball. It’s a filamentous, very delicate phase. To date, nobody has really completed the life cycle of Asparagopsis in cultivation. In my laboratory at Scripps, we’re manipulating things like light, temperature, and nutrient concentrations to explore growth rates and
chemical composition of the tissue. If you can alter light or temperature and
you can get a doubling of growth, that’s going to be really important for thinking about scaling up cultivation. Like the UC Davis team, this research
project is at very early stages. There’s so much to be done, and it’s such
an exciting time. Ultimately, what we need to know is how fast can we grow Asparagopsis, how much space do we need, how much resources do we need, how can we scale this to make it viable as a supplement on a global scale. We don’t want to have a cultivation facility
that requires a ton of electricity and power in order to grow the seaweed, because we’re trying to, ultimately, reduce greenhouse gas emissions and reduce our carbon footprint. There’s hope that if this proves out, all
cows around the world could have this supplement added to their diets. It’d be a small tweak with big ramifications. I think every sector, including the animal agriculture sector, needs to find ways to reduce their overall greenhouse gas emissions. We have to be working towards a more sustainable system. It could be complementary to other things that would help in reducing emissions. And so if feeding seaweed at a cost effective way that doesn’t negatively affect these animals, I think it’s a viable way for us to actually meet those standards. For more science documentaries, check out this one right here. Don’t forget to subscribe and keep coming back to Seeker for more videos.