Methane is a potent greenhouse gas and a major contributor to climate change. About 70 percent of agricultural methane comes from enteric fermentation, chemical reactions that occur in the stomachs of cows and other grazing animals as they digest plants. Fortunately, studies have shown that adjusting cattle diets to include higher fat or more digestible ingredients, like algae, can make an impact in reducing these emissions. One 2015 study suggested that feeding cows seaweed could be potentially beneficial, but not until now has the theory been tested in real cattle populations.
A newly published study from the University of California, Davis put this theory to the test and found that using red seaweed as a feed supplement can successfully reduce both methane emissions and feed cost without sacrificing meat quality.
In their research, the scientists found that supplementing cattle diets with just 10 ounces of seaweed a day reduced methane emissions by 67 percent. They also found that the seaweed could be frozen for up to three years without sacrificing nutritional and emissions reduction benefits, making it as convenient as traditionally-stored feed.
One drawback noticed in the study was that milk cows fed the seaweed supplement did see reduced milk production, which would disincentivize dairy farmers from adopting the feed. On the other hand, steers who were fed the amended diet converted feed to body weight up to 20 percent more efficiently than conventionally-fed steers, which would greatly reduce input costs for cattle farmers to the tune of $40,320 to $87,320 per year.
Incorporating seaweed into cattle diets would be a relatively easy switch in the agricultural industry and one that we now see would have tremendous environmental advantages. Hopefully, this new research, which solidifies the benefits for both farmers and our world, will encourage farmers and feed producers to integrate seaweed supplementation in their operations.