Milk goes green: Cows fed rbST reduce agriculture’s carbon hoofprint

ITHACA, N.Y. — Producing milk uses large quantities of land, energy and feed. But cows that receive a biotech product called rbST give more milk, easing natural resource pressure and reducing environmental impact, according to a Cornell study.

The carbon hoofprint is being reduced by a biotech product used on American farms for nearly 15 years called recombinant bovine somatotropin.

Savings

The Cornell-funded research found that giving rbST to 1 million cows would enable the same amount of milk to be produced using 157,000 fewer cows than in a non-supplemented population.

This would conserve 491,000 metric tons of corn, 158,000 metric tons of soybeans and reduce total feedstuffs by 2.3 million metric tons. Producers could reduce cropland use by 219,000 hectares and reduce soil erosion by 2.3 million tons annually.

Using rbST is equivalent to removing approximately 400,000 cars from the road or planting 300 million trees.

“Supplementing cows with rbST on an industrywide scale would improve sustainability and reduce the dairy industry’s contribution to water acidification, algal growth and global warming,” said Judith L. Capper, Cornell postdoctoral researcher and lead author of the research paper.

Impact

In 2007, there were 9.2 million cows in the United States.

For every 1 million cows supplemented with rbST, the world would see an environmental saving of 824 million kilograms of carbon dioxide, 41 million kilograms of methane and 96,000 kilograms of nitrous oxide.

This reduction in the carbon footprint is equivalent to removing approximately 400,000 cars from the road or planting 300 million trees, Capper wrote.

“Sustainability is important in agricultural production, with an emphasis placed upon meeting human food requirements while mitigating environmental impact,” said co-author and animal scientist Dale Bauman.

“This study demonstrates that use of rbST markedly improves the efficiency of milk production, mitigates environmental impact including greenhouse gas emissions and reduces natural resource requirements, such as fossil fuel, water and land use.”