Scientists are breeding a herd of cows that produce lower-fat milk after the chance discovery of a natural gene mutation in one animal.
Milk from the cows is also high in health-boosting omega-3 fatty acids and makes butter that spreads as easily as margarine even when chilled, the New Zealand-based biotechnology company Vialactia said Monday.
Scientists discovered a cow, later named Marge by researchers, carrying the mutant gene in a dairy herd they were testing in 2001, Vialactia chief scientist Russell Snell said.
Vialactia, a subsidiary of the Fonterra Cooperative Group, one of the world's largest milk companies, bought the cow for $218 (300 New Zealand dollars) and moved it to a research site.
While she looked like any other Friesian cow, testing revealed that Marge's milk contained about 1 percent fat, compared with about 3.5 percent for whole milk. Fonterra said that products made from the milk "maintain the positive taste with other desirable benefits," and Snell said the milk contained normal levels of protein.
Offspring from the cow also produce low-fat milk, showing that the genetic trait is dominant, Snell said.
Scientists have yet to isolate the exact chemical pathway responsible for the naturally produced low-fat milk, Snell said.
"Every now and then nature throws up these sorts of things, and it was simply a case of us being in the right place at the right time," he said.
A research report on the genetic twist is due to appear in the British journal Chemistry & Industry. The company expects the first commercial herd of cows supplying natural low-fat milk and spreadable butter for the market by 2011.
This report includes information from The Associated Press and MSNBC.com.