Move to cut methane emissions by changing cows' diet  · More
digestible feedstuff reduces production of gas · Farmers could
switch to different grass varieties  Burping cows and sheep are
being targeted by UK scientists to help bring down Britain's
soaring levels of greenhouse gas pollution. Experts at the
Institute of Grassland and Environmental Research in Aberystwyth
say the diet of farmed animals can be changed to make them
produce less methane, a more potent global warming gas than
carbon dioxide. Farmed ruminant animals are thought to be
responsible for up to a quarter of "man-made" methane emissions
worldwide though, contrary to common belief, most gas emerges
from their front, not rear, ends.  Mike Abberton, a scientist at
the institute, said farmers could help tackle climate change by
growing grass varieties bred to have high sugar levels, white
clover and birdsfoot trefoil, a leafy legume, for their animals
to eat. The altered diet changes the way that bacteria in the
stomachs of the animals break d