Photo: Photos by Gabrielle Lurie / The Chronicle
DAVIS – The biggest issue in the fight against global warming may not be whether humans can feed on fossil fuels, but whether farmers can control their incessantly burping cows ,
Researchers at UC Davis said last week that they may have found a superfood that will reduce the amount of methane when they burp, what they do a lot and collect a huge amount of greenhouse gas into the atmosphere.  The solution, said Ermias Kebreab, Professor of Animal Sciences at UC Davis, is a touch of seaweed mixed with molasses and stirred in the feed. Sea algae inhibit an enzyme that contributes to methane production in the gut
"We have seen a dramatic fall in methane emissions, well over 30 percent … by feeding about 1 percent of the food as seaweed," Kebreab said from the dairy cattle shed UC Davis, where he and his colleagues have tested the marine delicacy on 12 Holstein cows over the past month and a half. "This could help California dairy farmers meet new methane emissions standards and sustainably produce the dairy products we need to feed the world."
Californian lawmakers have recently passed regulations requiring dairy farmers and other producers to cut methane emissions by 40 percent by 2030. This requires controls over which substances spew out the 1.8 million dairy cows in the state when belching.
Photo: Gabrielle Lurie / The Chronicle
These cows regularly receive feed for the UC Davis study.
These cows regularly receive food for the UC Davis study.
"Since the methane emissions of many dairies come from the animal itself, nutrition can play a major role in finding solutions," said Kebreab.
The early-stage methane study is the first in the world to be conducted with dairy cows, but it could have far-reaching consequences in California, one of the most stringent emissions standards in the United States.  Scientists have found that about 8 percent of the greenhouse gases in the atmosphere come from agriculture, and at least 30 percent of the total agriculture comes from methane released from cattle. Contrary to popular belief, most of the gases that escape from the cows do not come from the rear.
"That's a big misunderstanding, with about 95 percent coming out through the mouth or nostrils, like the front end of the cow," Kebreab said, adding that fertilizer is the source of most of the remaining methane.
Kebreab's team is planning a six-month trial on oxen starting next month, but the first results on the cows were pleasantly surprising, he said. He could not state the exact methane reduction percentages – these will be released in June – but he said, "It's really outrageous, really unusual, to see this kind of effect on an animal."
The hope is that studies on the next five years will have no negative impact on cows, their milk or, in the case of beef cattle, on their meat. Researchers will also examine whether kelp infusions help reduce methane emissions in cow dung.
Photo: Gabrielle Lurie / The Chronicle
UC Davis Professor Ermias Kebreab keeps the seaweed-infused food he is studying to reduce the amount of methane in beef bulls.
UC Davis Professor Ermias Kebreab keeps the algae-infused …
The idea of testing algae came from Australia, where laboratory technicians discovered that a 2% algae mixture could reduce methane emissions by 99%. The laboratory tests conducted in 2016 showed that the most effective seagrass species was Asparagopsis taxiformis, which is considered invasive in many places.
The kelp called Armata was also effective – and it may possibly be grown in California – so Kebreab and his team have decided to test it on living animals first.
The algae are freeze-dried and shipped from Australia. The molasses is used to mask the odor and make the food taste better.
The problem is that there is not enough kelp naturally used in livestock feed. Several fish farms in California are now trying to grow the species commercially, but Kebreab said it would take at least five years for seagrass-infused food to be commercially available.
During the study, Kebreab and his assistant Breanne Roque have separated the cows into three quads. One group received feed with 1 percent algae, the second group got half a percent and the rest of the animals did not eat algae. The cows were shot during a two-week feeding regimen with an intermediate, one-week kelp cure.
The measurements were made during the four daily feedings using a Breathalyzer-type device that measured the methane in cow breath during the meal.
Kebreab's team will release the preliminary results in late June and will begin additional testing with additional cattle later in the summer.
Peter Fimrite is an associate of the San Francisco Chronicle. E-mail: [email protected] Twitter: @pfimrite