| CHICAGO, June 30
CHICAGO, June 30 Using bovine growth hormones
to boost milk production could help the dairy industry
significantly reduce its impact on the environment, U.S.
researchers said on Monday.
They said supplementing 1 million cows with the growth
hormone recombinant bovine somatotropin or rbST would have the
same effect as removing about 400,000 cars from the road or
planting 300 million trees.
"That's a pretty substantial impact," said Dale Bauman of
Cornell University, whose research appears in the journal
Proceedings of the National Academy of Sciences.
While it has been approved for sale by the U.S. Food and
Drug Administration since 1993, the hormone has been banned in
Japan, Australia, Canada and parts of Europe. Opponents say it
can have harmful effects on both the cows and humans who drink
Many U.S. grocery chains in the United States have switched
to milk suppliers that do not use the synthetic hormone, and
Wal-Mart Stores Inc said in March its private label brand of
milk would be sourced from suppliers that do not use growth
Cornell University paid for the study, done with the help
of Roger Cady of Monsanto Co (MON.N), maker of the bovine
growth hormone Posilac.
The study focused on environmental, not safety, issues.
FEWER COWS, LESS FEED
The research suggests that, if used on a large scale,
bovine growth hormones could reduce the number of cows needed
to produce milk, cutting demand for corn and soybeans and
reducing greenhouse gas emissions by decreasing the amount of
manure they produce.
Decomposing manure produces methane, a greenhouse gas.
Scientists say controlling methane emissions from animals would
help address climate change.
"All food production has an environmental impact, but many
people don't realize that," Bauman said by telephone.
Bauman and colleagues used computer models to calculate the
impact that greater use of growth hormones might have. They
figured using the hormones would let 843,000 cows produce the
same amount of milk now produced by 1 million.
That would save 491,000 tonnes of corn, 158,000 tonnes of
soybeans, and total feed would be reduced by 2.3 million
tonnes. The change would allow farmers to reduce the amount of
cropland needed by 540,000 acres (219,000 hectares) and reduce
soil erosion by 2.3 million tonnes a year, they said.
And it would reduce carbon dioxide emissions by 1.8 billion
pounds (824 million kg), methane emissions by 90 million pounds
(41 million kg), and nitrous oxide emissions by 210,000 pounds
Michael Hansen, a senior scientist with Consumers Union,
said the study is based on a "false notion" that you can
produce the same quantity of milk with less feed.
Hansen said Monsanto in the late 1980s sought to make a
label claim that the product increased feed efficiency, but the
FDA said the company did not provide enough evidence for that
(Editing by Patricia Zengerle)