A bit of seaweed in cattle feed could reduce methane emissions from beef cattle as much as 82 percent, according to new findings from researchers at the University of California, Davis. The results, published today in the journal PLOS ONE, could pave the way for the sustainable production of livestock throughout the world.
“We now have sound evidence that seaweed in cattle diet is effective at reducing greenhouse gases and that the efficacy does not diminish over time,”
Over the course of five months last summer, Kebreab and Roque added scant amounts of seaweed to the diet of 21 beef cattle and tracked their weight gain and methane emissions. Cattle that consumed doses of about 80 grams (3 ounces) of seaweed gained as much weight as their herd mates while burping out 82 percent less methane into the atmosphere. Kebreab and Roque are building on their earlier work with dairy cattle, which was the world’s first experiment reported that used seaweed in cattle.
Results from a taste-test panel found no differences in the flavor of the beef from seaweed-fed steers compared with a control group. Similar tests with dairy cattle showed that seaweed had no impact on the taste of milk.
Also, scientists are studying ways to farm the type of seaweed—Asparagopsis taxiformis—that Kebreab’s team used in the tests. There is not enough of it in the wild for broad application.
Another challenge: How do ranchers provide seaweed supplements to grazing cattle on the open range? That’s the subject of Kebreab’s next study.
Also, do the bovines eat the seaweed happily or do they need to be force fed it?