An enriched fermented seaweed additive which reduces methane emissions by more than 10% in cattle and sheep has recently been developed by Teagasc researchers.
The additive can be used in a pasture-based system without negative effects on feed intake, the environment, animals, or farmer and food safety, Teagasc said.
The methane-reducing feed additive, with “minimal effects” on farm preparation, has been tested using rumen simulation technique (RUSITEC) systems, and in beef and sheep.
Seaweed feed additive
As part of the SeaSolutions project between European and Canadian partners, Teagasc researchers developed a number of different ingredients from several native seaweeds.
The project aims to develop novel, science-based, and implementable approaches to reduce methane emissions from sheep, cattle and dairy cows through seaweed feed additives.
Over 70 seaweeds were tested in trials with seaweed and seaweed-derived ingredients as part of this research, which resulted in the development of about 10 ingredients from the sea.
Of those, two seaweed-derived ingredients showed a 36% reduction in methane and methane-producing bacteria in-vitro, using the rumen simulation model at Teagasc.
Cattle and sheep trials
Trials with indoor sheep and cattle, which were fed a fermented Irish seaweed at 2-4% of the total dry matter intake of the animal for a three-to-four month period, yielded a 10-11% reduction in methane.
“The ingredient is naturally derived and it produces a methane-reduction effect comparable to some other products that are out there currently that are synthetic.”
This is according to senior research officer at the Teagasc Ashtown Food Research Centre and coordinator for the SeaSolutions consortium, Dr. Maria Hayes.
Teagasc researchers are currently developing a bolus-feeding type product using a seaweed extract which is being trialled in the in-vitro system, according to Dr. Hayes.
“To maybe administer the product to younger animals and maybe affect the ruminant at an earlier stage, and assess whether our ingredient can have a long-term effect,” she added.
In terms of a grass-based system, Dr. Hayes said that the development of a water-soluble extract using the methane-reducing technology might be an option for outdoor grazing systems.
The same seaweed feed additive which resulted in methane reductions in sheep and cattle was trailled in a dairy system by SeaSolutions project partners in Sweden, she added.
While Teagasc has carried out trials with dairy cows outdoors using a different seaweed, the researchers would like to trial the additive used in Sweden based on a positive result.
Further research
The developed seaweed ingredient may also have other health benefits for cows, sheep, and cattle which the Teagasc researchers hope to explore further.
“This provides an additional benefit to methane reduction in terms of animal health that existing products for methane reduction do not have,” Dr. Hayes said.
A patent is currently in place on the product, she added. Research funding has been provided by the Department of Agriculture, Food and the Marine (DAFM) as part of the SeaSolutions project.