Research shows that feeding seaweed to cattle can significantly reduce methane emissions and improve feed efficiency, offering a sustainable solution for livestock farming.

With the focus on reducing methane gas production and other greenhouse gases, attention has been on cattle since methane is produced in the rumen by microbes that ferment feed and break it down into nutrients. Fermentation digestion also generates byproducts the cow’s body can’t utilize, such as carbon dioxide and hydrogen. Methane-producing microbes use these compounds to form methane, which the cow expels.

Research has shown that various types of seaweed can be fed to cattle, altering the chemical process in the rumen, reducing the amount of methane belched out. Many plant extracts have been tried, such as oregano, lemongrass, garlic, and various citrus products, with disappointing results. The trials in Australia looked at several species of seaweed because they produce many chemical compounds. In the original trial, one species stood out above all others in terms of reducing methane production–Asparagopsis taxiformis. After that study was published in 2014, livestock scientists began testing with live animals.

The first UC Davis trial was with dairy cattle, feeding seaweed for 30 days, with consistent results–about 50% reduction in methane–just feeding small amounts. In this study the seaweed was about 1% of the total dry-matter intake. The trials also showed that feeding seaweed made the animals more feed efficient. Methane is a waste product (from digestion breakdown), and this carbon-based molecule is no longer being released as waste.

Today, there is a global seaweed aquaculture industry. Some seaweed crops are large, such as seaweeds grown for sushi. There are huge farms for that, in Asia. There is a potential market for red seaweed for livestock feed. This is an exciting solution for the livestock industry, which is currently facing political efforts to restrict greenhouse gas production. It only takes a tiny amount of supplement to make a big difference. There are groups in Australia, New Zealand, Europe, Southeast Asia and the U.S. working on products.

There’s been improved health and well-being of the animals and their feed efficiency. This may help make the livestock industry be more sustainable and meet the demand for reduction of greenhouse gases.

Another study was completed four years ago at Thompson Rivers University in Kamloops, British Columbia. They did a 2-year trial with seaweed feeding red seaweed from the West Coast. This trial showed different types and amounts of bacteria in the rumen of cattle fed seaweed versus those that weren’t. Feed efficiency was improved, the animals gained more weight, and levels of fatty acids like CLA, omega 3, omega 6, etc. that provide health benefits of grass-fed beef were also changed.

Much of the research on seaweed in North America as a potential feed additive is with Asparagopsis taxiformis. This red seaweed is successful in methane reduction because of its high concentration of bromoform, a secondary metabolite that helps seaweed survive in stressful environments. When ingested by cattle, it can competitively inhibit an enzyme involved in methane production. This seaweed is not indigenous to our waters, however; it thrives in tropical and subtropical waters. Brown seaweeds don’t typically produce bromoform, but produce other secondary metabolites of interest including phlorotannins.

With results of this research and future feed trials, maybe agriculture and aquiculture can partner and find solutions to make this sector of agriculture more sustainable. Cattle and sheep eat seaweed if they have access to it. Farmers in Ancient Greece grazed cattle near beaches to eat seaweed that washed up, because of the productivity benefits, as did Icelandic farmers in the 18th century.

The first commercial sales of freeze-dried Asparagopsis were in 2022 and licenses granted to seven more companies in Australia, Sweden, USA and Canada, Asparagopsis can be harvested from a seaweed farm and freeze-dried to preserve bioactivity when packaged and transported. It can also be steeped in an edible oil, such as canola.

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SPRING LANDSCAPE MANAGEMENT

We are actually having real spring weather it appears. We are not going from late winter straight into summer. We are still in a drought, but spring is here so now we can straighten up and spruce up the home landscape.

We can start by getting rid of weeds. This long drought has led to an increase in weeds. We are seeing some new broadleaf weeds we didn’t have before. If you do not have many trees and shrubs in your landscape, then a weed-and-feed all in one product will probably work. If you do have trees and shrubs, then weed-and-feed products are not recommended. The weed part is actually an herbicide, and it can be detrimental to your yard trees and shrubs. It is recommended to control the weeds in the lawn prior to applying fertilizer. We don’t want to fertilize the weeds. There are some good post-emergent sprays that are labeled to use in the yard to continue to raise the mowing height. You do not want your turf grass to be short/scalped once we get into the hot summer temperatures.

After you have mowed a few times this spring then we can apply fertilizer. Select a granular fertilizer blend that has a 3-1-1 or 3-1-2 ratio of the three main ingredients nitrogen, phosphorus, and potassium. So, a blend similar to 15-5-5 or 15-5-10 is recommended. The amount of fertilizer to apply to your yard is based on nitrogen, the first number on the bag. If you purchase a 50lb bag of 15-5-5 fertilizer, there will be 75lbs of actual nitrogen in that bag. It is recommended to apply 1lb of nitrogen per 1,000sq ft. Most people over fertilize. Be sure to water in the fertilizer well to avoid burning the turfgrass with the fertilizer.