May 20, 2009 -- As new fuel efficiency standards for cars make news in the United States, scientists in Canada are already developing more fuel-efficient, and more polite, cattle.

The research promises to lower costs to farmers by reducing the amount of feed needed for raising cattle. It could also help the environment by reducing the number of methane released into the atmosphere, where it is a climate-warming greenhouse gas.

"Ruminants produce a lot of methane; three cows equal one [mid-sized] car" in terms of global warming potential, said John Basarab, an agricultural research scientist for the Alberta government.

"In Alberta alone there are more than six million cows, and in the U.S., there are over 100 million," he said. That's a lot of methane.

The man behind the effort is Stephen Moore, a agriculture research scientist from the University of Alberta. Moore is greening cattle in two ways, by modifying the food cows eat, and by modifying the cattle themselves.

By selectively breeding cows that are more fuel-efficient, Moore has created a line of cattle that produce 25 percent less methane than the average bovine.

But breeding is old school. Genetically engineering cattle to produce less methane could produce even more fuel-efficient animals. In preliminary genetic studies, Moore and his colleagues have identified 20 areas of the bovine genome that influence methane emissions.

The genetic engineering process is fairly complex, since it isn't the cows themselves that produce the methane. The bacteria that live in a special organ, the rumen, produce the greenhouse gas after breaking down cellulose in the grass, hay, oats, grain and ash in cattle feed. Those 20 relevant areas of the bovine genome, which contain an unknown number of actual genes, regulate the immune system, which keeps in check the bacteria that live in the rumen.

"Methane is produced by bacteria, and we can breed animals that produce less methane, so there is obviously a link between the two," said Moore. "The animal is very good at controlling what lives inside it."

It's not just about the engine, however. The fuel also helps determine how much methane is emitted. Moore's research correlating feed with methane emissions is still preliminary, but he is trying to create cow feed that reduces methane but is still affordable to farmers. His initial results are detailed in a new study in the Journal of Animal Science.

In general, cows that eat high-cellulose diets like grass and hay produce more methane than those on a diet high in grain. Adding supplements like fish oil to the grain reduces cow burps, but can be expensive. A one-diet-fits-all approach won't work; a variety of feeds are necessary depending on the needs of the cow.

"We know we can reduce methane emission from diet," said Morre, admitting, "it's a complicated system."

The incentive for farmers to use low-emission cattle is two-fold. First, fuel-efficient cattle will reduce the amount of money farmers spend on feed.

The "icing on the cake," according to Basarab, is that farmers who reduce their carbon dioxide equivalency (CO2e) credits can then sell them to companies who emit greenhouse gases under Alberta's greenhouse gas cap-and-trade system.

"Alberta has a big oil industry, which would be buying the carbon credits," said Moore. "Right now we are validating the technology so that farmers can sell their carbon credits. They could use the extra money."