UC Davis discovered a way to reduce methane emissions from cattle
By AARYA GUPTA — science@theaggie.org
An article published by the University of California Office of the President deemed UC Davis’ research on the effects of feeding cattle seaweed on greenhouse gas emissions as one of the top 10 research stories of 2021.
Professor and Sesnon Endowed Chair of the Animal Science Department Ermias Kebreab and graduate student Breanna Roque published the results of their study in March 2021 in the PLOS One Journal.
“We have been working on methane reduction [for] two decades already,” Kebreab said via email. “The renewed interest in climate change gave us the opportunity to continue in this line of work. Livestock contributes [a] considerable amount of methane so we wanted to find [a] solution for reduction.”
According to an article published by UC Davis, the number one source of greenhouse gases emitted from the agriculture sector is cattle. In particular, one cow can emit 220 pounds of methane each year. In comparison to carbon dioxide, methane is 28 times more potent.
“The state of [California] has a mandate to reduce methane emissions by 40 percent by 2030,” Kebreab said. “As a public university, UC Davis is charged with finding solutions to our stakeholders and to our state in general. So it is important that UC Davis find solutions to help farmers reduce their carbon footprint.”
Kebreab and Roque’s experiment followed a completely randomized design, and collected data from 21 Angus-Hereford cross beef steers, which were all randomly assigned to three different treatment groups.
“The main take-away is that by using such a small amount of seaweed[,] we can reduce emissions by over 80 percent, which is the first time such reductions were observed in livestock,” Kebreab said.
After feeding the beef cattle seaweed, researchers concluded that cattle that consumed approximately 80 grams of seaweed emitted 82% less methane into the atmosphere, while gaining the same amount of weight as other cattle in their herd, according to the article.
“It is incredible to learn about how UC Davis is researching ways to reduce greenhouse gas emissions and discovering novel sustainable practices to improve the livestock industry overall,” third-year animal science major Azra Mahic said.
These results pave the way for a more sustainable production of beef and dairy products. Kebreab and Roque’s study also uncovered that seaweed had no effects on the taste of beef or milk.
“The main greenhouse gas from cattle is methane so by reducing methane from livestock we can have [a] much more environmentally sustainable production system,” Kebreab said.
Similarly, third-year design major Emma Smith said she was intrigued by the applications of seaweed in animal sciences after learning about seaweed farming as a sustainable crop in her classes at UC Davis. Smith is also minoring climate science and policy and sustainability in the built environment.
“It is really exciting to hear that researchers here at UC Davis are using the superpower of seaweed to contribute to more sustainable practices when it comes to cattle,” Smith said. “Not only is seaweed an important carbon sink, but it is super exciting to hear that it can reduce methane emissions from cows.”
Written by: Aarya Gupta — science@theaggie.org
