By
updated 5/18/2012 3:28:19 PM ET 2012-05-18T19:28:19

Officials have lifted quarantines on two Central California dairies linked to a case of mad cow disease, after investigators found the illness didn't come from cattle feed.

  1. Don't miss these Health stories
    1. Splash News
      More women opting for preventive mastectomy - but should they be?

      Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

    2. Larry Page's damaged vocal cords: Treatment comes with trade-offs
    3. Report questioning salt guidelines riles heart experts
    4. CDC: 2012 was deadliest year for West Nile in US
    5. What stresses moms most? Themselves, survey says

Tests performed by the World Organization for Animal Health confirmed what U.S. labs had found: The diseased cow had a form of the illness involving a spontaneous mutation of a protein gene that hasn't caused illness in humans.

The cases of mad cow reported across Great Britain in the 1990s were caused by cattle being fed protein supplements made from the spinal columns and brains of diseased cows. That practice has since been banned.

The case in Tulare County was discovered through random testing.

Officials have not released the names of the affected dairies, which had been shuttered since April 24.

Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Discuss:

Discussion comments

,

Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments