Livestock is responsible for almost 15% of global greenhouse gas emissions. Most of that is in the form of methane that cattle release when they burp. Grazing cattle produce more methane than feedlot cattle or dairy cows because they eat more fiber from grass. There are 9 million dairy cows in the U.S. but more than 64 million beef cattle.
Beef cattle spend most of their lives grazing in pastures and producing methane. Controlling the food of pasture-raised cattle is difficult because they often graze far from ranches for extended periods of time. During the winter and during times when grass is scarce, ranchers supplement the diet of cattle.
A new study by researchers at the University of California – Davis has found that feeding grazing cattle a seaweed supplement in pellet form reduced their methane emissions by nearly 40% without affecting their health or weight. There have been previous studies that showed seaweed cut methane emissions by 82% in feedlot cattle and over 50% in dairy cows. But this is the first study to test the effects of seaweed on grazing beef cattle.
The seaweed pellets were made available to grazing cattle and they ate the supplement voluntarily. Compared to a group of cattle who didn’t receive the supplements, the seaweed eaters had a 40% reduction in methane emissions.
Other research studies to reduce methane emissions using feed additives have taken place in controlled environments with daily supplements. This method provides a way to make a seaweed supplement easily available to grazing animals. It could even be introduced through a lick block for cattle.
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Feeding Grazing Cattle Seaweed Cuts Methane Emissions by Almost 40%
Photo, posted February 18, 2016, courtesy of Beverly Moseley/NRCS via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio
