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Researcher Says Selective Cattle Breeding Is Good For The Planet

Dave Young
/
Flickr, Creative Commons

The days of guess work in breeding dairy cattle are gone. Today's DNA sequencing means more productive cows and less pollution.

Breeding cattle through artificial insemination began in the 1940s. Farmers bred cows with bulls who fathered fertile, healthy and robust daughters. Today animal breeders choose mates based on their DNA.

“And what that has effectively has done is enabled us to dramatically reduce the size of the dairy herd in the United States,” says Alison Van Eenennaam, an animal geneticist at UC Davis. “So we used to have somewhere roundabouts 25 million dairy cows in the United States, and we're down to nine [million] now.”

She says selective breeding is good for the planet because fewer dairy cows are releasing methane – a harmful green house gas.

"It’s actually reduced the environmental footprint of a glass of milk by two-thirds relative to the 1950s," she says.

Mapping the cow genome was completed in 2009. Van Eenennaam says teasing out which genes contribute to specific traits will continue to help animal breeders improve the dairy industry's productivity.