FEEDING dairy cows oilseeds or feeds high in fat substantially curbs emissions of a powerful greenhouse gas, according to new research by the Department of Primary Industries (DPI).
Scientists from DPI Ellinbank found that for every 1 percent increase in dietary fat, methane emissions were reduced by 3.5 percent.
DPI Dairy Nutrition Scientist, Dr Peter Moate said the research also found that adding the extra fats did not restrict feed intake, milk production or fat and protein yields.
“All this research plugs a knowledge gap in that our scientists have determined how much we can expect to cut methane emissions when cows are fed oilseeds or fatty feed supplements.”
Dr Moate said the researchers at Ellinbank fed dairy cows supplements of either crushed wheat, cold-pressed canola, hominy meal or a blend of hominy meal and cold-pressed canola (all high-fat).
The cows were housed in respiration chambers and their daily methane emissions measured.
A typical dairy cow produces 400-500 grams of methane a day. Scientists are concentrating on methane because it has global warming potential 21 times greater than carbon dioxide.
“In a carbon-constrained world, if pricing structures change or emissions targets become mandatory, dairy farmers will be forearmed with information they can use to reduce methane emissions from their cattle,” Dr Moate said.
The nutrition research at DPI Ellinbank is part of a range of research programs funded by DPI to reduce greenhouse gas emissions and develop adaptation strategies for food and fibre producers.