Question
To ask the Secretary of State for Environment, Food and Rural Affairs what assessment she has made of the potential for reductions in greenhouse gas emissions from agriculture of alterations in the feedstuffs provided to livestock.
Answer
DEFRA has funded research to investigate the potential for reducing greenhouse gas emissions from livestock by dietary and nutritional control. These studies have showed that feeding ruminant livestock foods such as maize silage, naked oats and higher sugar grasses can reduce the amount of methane they produce.Research carried out by Reading University and the Institute of Biological, Environmental and Rural Sciences (IBERS), under projects commissioned by DEFRA in January 2005 and April 2007, showed that it is nutritionally possible to reduce nitrogen excretion from cattle and sheep and their methane emissions. For example: increasing the proportion of maize silage from 25 to 75% in a short-term trial was found to reduce methane emission per kg milk by 6%; high-sugar grasses could reduce an animal's methane emissions by 20% for every kilo of weight gain; naked oats could reduce methane emissions from sheep by 33%; and crushed rapeseed could reduce methane production from dairy cows by 20% per litre of milk produced. In the longer term, the benefits gained by changing animals' diets will need to be considered against other environmental impacts, as well as how practical or costly they are for the farming industry to implement.