AUSTRALIAN animal nutritionists have found that dietary seaweed could offer a means of dramatically cutting the problematically large amount of greenhouse gas emitted by livestock farming around the world, while also boosting its productivity.

The researchers, at James Cook University in Queensland, Australia, had been building on the experience of a Canadian farmer, who discovered that cattle eating wind-blown seaweed were not just healthier than others, but enjoyed a longer mating cycle too. It has emerged that these effects were a product of better nutrient utilisation due to changes in how cattle and sheep gut microbes were digesting fodder.

Following promising laboratory results in 2015, the researchers have been trialling feed rations containing a small amount of dried seaweed of the species Asparagopsis taxiformis, which releases the compound bromoform, which in turn disrupts the enzymes used by the gut microbes that produce methane gas as waste during digestion.

The results have been startling, with just 2% seaweed content added to feed cutting methane emissions by as much as 99% in some animals, alongside consistent results of 50% to 70% reduction recorded in sheep over a 72-day period.

With livestock responsible for 44% of all human-caused methane – which has 36 times the global warming potential of CO2 – the discovery raises the possibility of an economic and practical way to vastly improve the green credentials of dairy and red meat.

Scots Tory MSP, John Scott, commented that the Scottish Government should, at the earliest opportunity, commission research to build on the Australian evidence and explore its applicability to Scottish livestock farming.

"If methane emissions can be reduced by 70% by the addition of a small portion of dried seaweed to cattle and sheep diets, this could allow Scottish farming to play a still more significant role in achieving Scotland's carbon reduction targets," said Mr Scott.

"Further examination of this idea needs to be carried out urgently by ScotGov and our research institutions."