From Civil Eats:
Research suggests that adding red seaweed to cattle feed makes then burp 60 percent less. Now, some scientists are seeking to do it at scale.
Over the past few months, graduate students and researchers at California’s Moss Landing Marine Laboratories have scoured coastal waters, collecting seaweed in the hopes of finding a native species that could help gassy cows.
Cows belch—a lot. And their burps (as well as those of other ruminants) make them the top polluters of methane, a greenhouse gas that is 30 times more potent than carbon dioxide. As pressure to reduce heat-trapping gases in the atmosphere mounts, an increasing body of research has shown that seaweed added to cattle feed could dramatically reduce livestock’s impact.
The challenge: where will the enormous supply of seaweed—enough to impact millions of cows—come from? And at what cost?
Most scientists have focused on one red seaweed species—asparagopsis taxiformis—which thrives in tropical and sub-tropical climates. While asparagopsis can be found in Southern California, its habitat in the U.S. is relatively small since it’s a warm-water species. There are also concerns about it being invasive.
The hope is that a native seaweed alternative can be found to allow for sustainable cultivation in California. Simultaneously, researchers are studying the local asparagopsis strains, to better understand their life cycle and how they could be safely cultivated at a large scale in on-land tanks or off the California coast.
Currently, the asparagopsis used for research is imported from Australia, Asia, and Europe. It is not cultivated or sold anywhere, so divers must be hired to pick it in the wild, making it expensive. If it were grown at scale for cattle to reduce emissions, it would cost less; most seaweed grown on ocean farms around the world is already quite cost-efficient.
“If we’re going to use seaweed to feed cows and do it on an impactful scale, there’s an interest in local sources, so we’re not sticking it on a boat, burning a bunch of fuel and bringing it to California,” said Jen Smith, an associate professor at the University of California, San Diego, who studies asparagopsis native to the state. “We’re interested in growing it here.”
Cows’ Gassy Problem
Cows are, literally, a massive contributor to global warming. According to the Food and Agriculture Organization of the United Nations, the world has 1.468 billion head of cattle (compare that with 7.7 billion humans), with Brazil, India, China, and the U.S. raising the most cattle. As of January 2019, the U.S. had nearly 32 million beef cattle and just over 9 million dairy cows. (Calves don’t emit much methane because they are fed milk, or milk replacer, and have not yet developed a rumen.)
It’s no wonder the livestock sector contributes 14.5 percent of global greenhouse gas emissions—more than the entire global transportation sector. And when it comes to methane gas, livestock’s contribution is much bigger: 44 percent. Most of the methane produced by cows is a by-product of their digestion, known as enteric fermentation, a process during which microbes in the cow’s digestive tract decompose and ferment food. A smaller percentage of the methane comes from cows’ manure.
Manure digesters, large tanks that capture the methane biogas from manure and convert it into electricity, can curb some of these emissions. But there’s no way to collect cows’ burps into a tank. Researchers have tried to solve the problem for years by feeding cows things like oregano, tea leaves, citrus extract, and garlic. They also came up with a synthetic material called 3-nitrooxypropanol, or 3NOP. While some of these solutions show promise, their reductions in methane are modest. .......MUCH MORE
It's been a half-decade since we've posted on this stuff but since it's back in the news here are some prior posts:
April 2014
The White House Is Searching for the NextGen Futurecow (MOO)
February 2009
Farmers Relax (a Little) After Cow Tax Scare
July 2007
Cows that burp less seen helping in climate fight
There are more, if interested use the 'search blog' box upper left.
For what it's worth the citrus garlic cows sound like they could be yummy.
