Fonterra is partnering with Sea Forest to see if using seaweed in stockfeed can reduce emissions from commercial dairy herds.
The trial will use Asparagopsis, a seaweed grown naturally in Australia and New Zealand, as a feed supplement during the coming season.
In laboratory testing led by CSIRO, seaweed has shown the potential to reduce emissions from cows by more than 80 per cent.
Fonterra Australia sustainability manager Jack Holden said helping farmers reduce methane emissions was a priority for Fonterra.
"Early testing shows the potential for these emissions to be reduced by incorporating natural seaweed into cows' diets, so we are keen to see if those test results can be replicated in dairy herds at scale," he said.
Mr Holden said the trial would start with one farm in Tasmania and, if successful, expand to a small number of additional farms.
"Part of the reason for the trial is to better understand the impact on milk production, if any, and we look forward to seeing the results," he said.
"The trial will be tightly controlled to ensure the cows and their milk are safe."
There would be no cost to farmers participating in the trial.
"Like any trial, the unit cost will continually decrease if the trial is successful," Mr Holden said.
"We want this innovation to be widely adopted, so we know we need to make it cost-effective for farmers."
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