Feeding cattle seaweed reduces their greenhouse gas emissions 82% | Hacker News Reader

Feeding cattle seaweed reduces their greenhouse gas emissions 82%

phys.org

34 pointsWaitWaitWha9 comments

Here in New Zealand we have a lot of cows, with cow farms replacing sheep farms over the past two decades.

The government and our largest dairy co-operative have been looking into seaweed for a while now and it looks like production of seaweed cow feed is about to get underway:

https://www.rnz.co.nz/national/programmes/ninetonoon/audio/2...

Wow, thanks for the link! One of the interesting bits:

“Salmon is an example and you are restricted on the basis of the nitrogen output of those fish. If seaweed, asparagopsis in this case, is planted downstream, one of the foods it likes to eat is nitrogen."

Aren't people concerned about the fact that if you feed cows seaweed it can inhibit an enzyme in the cow's digestive system that produces methane? Sure, there'll be less methane but the cow also won't be digesting its food correctly.

Why assume it is harmful to their digestion? If I can eat beans without getting the discomfort of gas, I probably eat more beans. Article indicates they grow to healthy weight, the beef/dairy doesn't taste different. Sounds like they designed the bovine version of GasX.

That's science. Sounds like good work. Hopefully they can overcome the seaweed cultivation obstacle mentioned.

Do the cows like seaweed? Serious question, if they are starving and nothing else is available I guess they will eat it, much like I would also eat things I wouldn't normally eat if I were starving, but is it ok to feed them stuff that only serves our purpose (if thats really the case)?

Cows like grain mostly since it's pretty easy energy. It's kind of like how we think of candy. But mostly they eat what's called silage. Silage is grass and hay which is primarily cellulose and a bit of chlorophyll.

If a cow doesn't like something it won't eat it unless it is all you feed it. They are pretty deft at picking around stuff they don't like. (They do this when grazing too) As I understand it, the seaweed is just a supplement added to the silage and they voluntarily eat it when it's supplied.

Cows aren't picky eaters. There was once a case where one was caught eating a python. But again, they are all unique individuals just like people. Some like stuff that others don't. Some get neurotic and eat rocks and dirt. I'm sure there are a quite a few cows that don't like seaweed but eat it anyways just for something to do.

https://www.abc.net.au/news/2020-10-28/cow-eating-snake-phot...

The cow farts are just a single issue with raising them for consumption. The bigger issue is a very poor calorie conversion. We have to use a lot more energy in food production when we consume beef rather than consuming the plant inputs directly

The article addresses this wrt land that is suitable for crops versus land that can only support grazing. It isn't zero-sum, so you can't assume we could "consum[e] the plant inputs directly."

Alternatively, we could just stop breeding and eating cows. We'd also then free up a lot of land for other purposes, including rewilding, and have a lot more food to feed people.

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