September 5, 2008 - Canadian scientists announce a discovery that paves the way for diagnostic testing of live cattle, rather than postmortem.
September 13, 2008 - An Alabama research study shows that mad cow disease can sometimes be caused by genetic mutations.
March 10, 2009 - An anti-malaria drug known as quinacrine, which had reportedly shown promise against mad cow disease, is found to have no affect on the disease according to a British medical study.
March 14, 2009 - U.S. government permanently bans the slaughter of cows too sick or weak to stand on their own, seeking to further minimize the contraction of mad cow disease.
March 28, 2009 - Mad cow research pathologist Antonio Ruiz Villaescusa of Spain dies from mad cow disease.
April 24, 2012 - The USDA confirms the fourth case of BSE, found in a dairy cow from central California. The announcement maintains that the cow was never presented for slaughter for human consumption and poses no risk.
May 2, 2012 (update for April 24, 2012) - The California Department of Food and Agriculture (CDFA) identifies the two offspring born to the positive cow in the last two years. One was stillborn. The other was sampled for BSE. The test results were negative.