Reducing the carbon footprint. Environmentalists tell us we should be doing everything we can to lower the amount of greenhouse gases and other pollutants being released into the atmosphere.

But what if someone said you could reduce the carbon footprint of your farm by planting more Bt cotton or corn or by using some other technology such as recombinant bovine somatotropin in dairy cows?

Scientists at Cornell University have released a study showing that increasing milk production by another 10 pounds per cow with the product can do wonders for reducing the carbon footprint of dairy herds. “The popular belief is that agriculture accounts for about 16 percent of greenhouse gas emissions,” said Jude Capper, a post-doctoral research associate at Cornell. “The figure is actually closer to 6 percent and dairy accounts for about 11 percent of that total.”

Capper, a speaker at the World Dairy Expo in Madison, Wis., showed a magazine cover of cows standing in a creek to illustrate how far dairy farmers have come on environmental issues. “That's a nice bucolic scene,” she says. “But if you did that today you would get hammered by EPA.”

The industry could be faced with similar problems in the future because of methane gas emissions and nitrogen leaching from cows and cow manure. (Capper, a native of Great Britain, pronounces the word me-thane with a long e.)

Increasing the productivity of cows with products such as rbST or Posilac could reduce the carbon footprint by continuing to lower the number of cows required to feed a growing world population.

Dairy cow numbers have been coming down as productivity has increased. In 1944, 25.6 million dairy cows were required to provide 117 billion pounds of milk. In 2007, 9.2 million cows produced 186 billion pounds of milk.

Another 10 pounds of milk would reduce the industry's carbon footprint by about 9 percent, says Capper. If 1 million cows produced an extra 10 pounds of milk per day, dairy farmers would need 2.5 million tons less feed per year and 540,000 less acres of cropland.

“We would save enough electricity to power 15,000 households, generate enough heat for 16,000 households and enough water to supply 10,000 households per year,” said Capper. “In all, we would lower greenhouse gas emissions by 1.9 million metric tons.”

To bring the numbers down to the local level, a herd of 150 cows that produced another 10 pounds would require 245 fewer tons of feed, 53 fewer acres of farmland and 132,000 fewer gallons of water. “It would mean the equivalent of removing 38 cars from the road,” she said. “Or it would be the same as planting 28,000 trees.”

Consumer advocates/environmentalists have opposed rbST in the past. It will be interesting to see how they react when they begin to hear how much of a reduction in the carbon footprint can be achieved through the use of the technology.