Is making seaweed silage a cost effective stock feed?

A recent AgriFutures Australia research project has found that the potential for Australian seaweed to revolutionise livestock feed is immense, however challenges related to sourcing and costs are currently hindering this potential.

The “Investigating the use of seaweed as silage in feed for ruminant livestock” project aimed to identify opportunities and challenges associated with incorporating seaweed as silage in the diets of ruminant livestock.

However, the research found that farmed seaweed is not a cost-effective option as a source of feedstock for silage or other agricultural purposes due to the high production costs and competition from other markets, notably nutraceuticals.

As beef and dairy producers increasingly use silage as a year-round supplement, the project sought to expand the future market for farmed seaweed within pasture-based livestock industries by cultivating new seaweed species suitable for silage feedstock.

This study has uncovered practical challenges that need to be addressed when considering seaweed as an agricultural input.

FOCUS Pty Ltd, Director, Dr Jane Stanley, explained how one of the researchers she had been working with had seen evidence that ensiling seaweed would make it more digestible for livestock.

Unfortunately, the practicality of producing seaweed on a commercial scale turned out to be more challenging than anticipated.

“We found that producing seaweed silage on a farm scale just wasn’t feasible. Farmers would need to source their own seaweed and prepare it for ensiling which proved to be a really labour-intensive process that just wasn’t practical,” Dr Stanley said.

The research also found that farmed seaweed is not a cost-effective option as a source of feedstock for silage or other agricultural purposes due to the high production costs and competition from other markets, notably nutraceuticals.

“Seaweed does have some potential for use in agriculture,” Dr Stanley explained, “though these uses need to compete with other products and cost-benefit analyses need to be undertaken to determine any additional co-benefits.”

The potential uses for seaweed were outlined in the “Practical use of seaweed as a farm input fact sheet”, which explored a number of options, from its potential as an alternative to synthetic fertilisers to acting as a methane suppressant in ruminant livestock.

Despite the challenges in seaweed farming, there was still the potential to utilise wild-harvested seaweed for agricultural purposes.

However, regulatory obstacles pose the main barrier to harvesting wild seaweed, something that Dr Stanley believed could be changed.

“Australia’s current regulations around managing seaweed are very hands-off,” explained Dr Stanley.

“These regulations restrict us from harvesting seaweed from where it is growing, as well as collecting it off the beach, which we call beach-wrack,” she said.

Abundant seaweed growth in the wild often results from pollution of waterways with nutrient run-off and it may be a beneficial intervention to harvest it. This is increasingly being realised overseas, and appropriate harvesting regimes are being established.

“While we know that seaweeds play a crucial role in water quality management and marine habitat preservation, it’s important that we strike a balance between conservation efforts and harnessing seaweed’s productive potential in agriculture,” she said.

“In some circumstances harvesting seaweed may actually help in restoring ecological health.”

Dr Stanley suggested that given the recent advancements in our understanding of seaweed’s potential in agriculture and the availability of high-quality information, it was time to reconsider Australian regulations. Her call to do so is outlined in the Seaweed Regulatory Reform Fact Sheet.

Senior Manager of Emerging Industries at AgriFutures Australia, Dr Olivia Reynolds, said that the industry implications of this research were far-reaching and valuable.

“Seaweeds play a crucial role in enhancing food security and providing high-quality nutrition. It is imperative to safeguard the ecological balance of seaweed cultivation habitats to prevent harm to living organisms,” Dr Reynolds said.

“This body of research emphasises practical ways for the industry to strike a balance between maintaining crucial marine habitats and productively using it in agriculture.

“Through initiatives like this, AgriFutures Australia remains committed to driving impactful research that will propel the industry forward.”

Dr Reynolds emphasised that collaborative efforts among researchers, policymakers, and industry stakeholders were essential to unlocking the full potential of seaweed in agriculture and overcoming current challenges.