FRESNO, Calif. -- Investigators looking into California's first case of mad cow disease say they have tracked down at least one of her offspring in another state.
Since there is no live test for the disease also known as bovine spongiform encephalopathy, it was euthanized and brain samples were sent to the national laboratory. The test was negative, officials said Wednesday.
The USDA announced April 24 that the nation's fourth case of mad cow disease was discovered in the 10-year-old cow. It had been euthanized at a Tulare County dairy a week earlier and sent to the Baker Commodities rendering plant near the Central California town of Hanford, where random testing happened to be taking place that day.
That dairy and another associated with it are under quarantine, which is standard procedure. The USDA has declined to name the dairies or the state where the offspring was found.
USDA officials also said on Wednesday that within the last two years, the diseased cow gave birth to a stillborn calf. They did not say how that carcass was disposed.
Officials also are investigating the calf ranch where the diseased cow was raised before she was sold into dairy productions. Investigators said they have been unable to locate for testing the cattle that were raised with the one who developed mad cow disease.
Mad cow disease is a deadly affliction of the central nervous system that can be transmitted to humans who eat meat from infected cows. The incubation period is two to eight years.
Cows can contract the disease by eating rendered remains from other sick cattle, which are processed into protein supplements. It's no longer legal to feed cattle to cattle, but rendered cattle are fed to chickens, and chicken droppings and spilled feed are rendered back into cattle feed.
The FDA and the California Department of Food and Agriculture have been examining feed records at the affected dairy and have identified at least 10 suppliers.
The USDA tests 40,000 of the approximately 35 million cattle slaughtered annually for BSE. Baker Commodities is a voluntary participant in the testing program.
The <a href="http://articles.cnn.com/2003-12-23/us/mad.cow_1_mad-cow-disease-fatal-brain-wasting-disease-bse?_s=PM:US" target="_hplink">first confirmed case</a> of mad cow disease in the U.S. involved an animal from a farm in Mabton, Wash. The Holstein had been <a href="http://www.nytimes.com/2004/01/03/us/way-to-track-us-cattle-isn-t-ready-for-quick-use.html" target="_hplink">imported in 2001 from Alberta, Canada</a>, along with 70 other cows. The animal was a "downer," which means it was unable to walk when it reached the slaughterhouse, a condition that mandates automatic testing from the USDA. Following the determination of mad cow, the processor, Vern's Moses Lake Meats, voluntarily recalled 10,410 pounds of raw beef amid concerns that products might be tainted. These cows, pictured at Sunny Dene Ranch in Mabton, were quarantined in the following months during an investigation.
The second confirmed occurrence of the disease in the U.S. was linked to a farm in Texas, though it appears to be the country's first home-grown case. <em>The New York Times</em> reported that the animal was about 12 years old at the time of its death. It had spent the <a href="http://www.nytimes.com/2005/06/30/national/30cow.html?" target="_hplink">entirety of its life</a> on the same Lone State ranch until it was taken to pet food plant Champion Pet Food, Inc. in Waco, Texas, where it died in November of 2004. The animal was a "downer" which pet food outfits often take since the USDA prohibits such cows for human consumption. Testing for disease is still mandatory, and meat from the animal did not enter the food supply, thanks to safeguards. <em>Photo by Flickr user <a href="http://www.flickr.com/photos/mdenhoedt/4627140451/sizes/z/in/photostream/" target="_hplink">MdenHoedt</a>.</em>
A cow in Alabama was the third confirmed case of mad cow in the U.S. CBS reported that USDA head veterinarian John Clifford assured the public that meat from the animal <a href="http://www.cbsnews.com/2100-201_162-1396022.html" target="_hplink">had not entered the food supply for people or animals</a>. The animal was also a "downer," which led to it being euthanized and tested. <em> Photo by Flickr user <a href="http://www.flickr.com/photos/shan213/5293549136/sizes/l/in/photostream/" target="_hplink">Shan213</a>.</em>
Earlier this year, <a href="http://www.huffingtonpost.com/2012/02/09/marin-mad-cow-disease_n_1266959.html" target="_hplink">two reported cases</a> of mad cow-related illness in Marin County, Calif., one fatal, turned out <a href="http://www.nbcbayarea.com/news/health/Mad-Cow-Didnt-Kill-Marin-Woman-Officials-139057459.html" target="_hplink">not to be linked</a> to the disease. The scare, however, leaves Americans shaken.
The fourth confirmed case of the disease was <a href="http://www.huffingtonpost.com/2012/04/24/mad-cow-disease-california-usda_n_1449871.html?ref=food" target="_hplink">traced to a dairy cow</a> in central California.