Researchers from Victoria’s Department of Primary Industries (DPI) have discovered an eco-friendly way to use the by-products of winemaking to improve the quality and quantity of milk production.
Scientists have found that supplementing the cows’ feed with the stems, seeds and skins from wine grapes reduced their emissions by 20 per cent, increased milk production by five per cent and increased the healthy fatty acids in their milk when green feed was not available.
The cut to emissions is thought to represent the largest reduction of its kind ever attained through the use of a feed supplement.
The scientists supplemented the diet of dairy cows with five kilos of dried grape marc over 37 days and compared the results with other animals fed conventional fodder. They then measured the cows’ milk yields, milk composition and methane emissions.
DPI scientist Dr Peter Moate says the researchers were stunned by the results.
“We now know that supplementing a dairy cows’ diet with dried grape marc increases the healthy fatty acids in milk by more than six times that of standard autumn fodder.
These particular fatty acids are extremely potent in their ability to benefit heart health and are also known to help fight cancer, diabetes and arthritis.” ”
On top of the cuts to emissions and the potential health benefits for milk drinkers, the discovery could provide tangible benefits for the wine industry.
There are currently around 200,000 tonnes of grape marc produced in Australia every year making it a readily available product for dairy farmer though there are limits to the movement of grape marc because of quarantine restrictions to prevent the spread of the grapevine pest phylloxera.
The Victorian dairy industry produces more than 85 per cent of Australia’s dairy exports. In 2010-11, Victoria produced 5.91 billion litres of raw milk from a dairy herd of around one million cows.
Peter Moate says the use of grape marc together with other methane reducing feeds could result in a reduction in methane emissions of up to 20,000 tonnes per year – the equivalent of taking about 200,000 cars off the road.