Placeholder Image

字幕表 動画を再生する

  • 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.

We are hooked on meat.

字幕と単語

ワンタップで英和辞典検索 単語をクリックすると、意味が表示されます

B2 中上級

海藻が気候変動を遅らせる方法 (How Seaweed Could Slow Down Climate Change)

  • 153 11
    Silvia W. に公開 2021 年 01 月 14 日
動画の中の単語