Mad Cow

When the cows went mad, UC Davis was there to help

By Pat Bailey
UC Davis News Service

Within the first day that the disease was discovered and publicly announced, UC Davis experts were giving advice nationally on mad cow disease.

When the United States' first case of mad cow disease shocked the nation just days before 2003 drew to a close, UC Davis faculty members were quickly sought out by news media to help the public better understand this mysterious fatal disease.

Is it safe to eat beef? Can you kill the disease by cooking the meat? How will the nation's agricultural industry and international trade be affected? These were just a few of the questions that peppered UC Davis veterinarians, food scientists, animal scientists and economists. Within a week, UC Davis faculty members were quoted by newspaper, television and radio reporters from New York to Taiwan.

By mid-January, the mad cow story had lost its fire and had moved to the back pages of newspapers. But the U.S. Department of Agriculture continued its methodical search for the 81 cows that had come to the United States from Canada along with the Washington state cow infected with bovine spongiform encephalopathy (BSE), also known as mad cow disease.

And at UC Davis, the California Animal Health and Food Safety laboratory, operated by the School of Veterinary Medicine for the state of California, continued to play a vital, frontline role in surveillance for mad cow disease.

Each year, the lab, which is funded by the California Department of Food and Agriculture, conducts diagnostic tests on surveillance tissue samples from approximately 10,000 sheep and 500 deer. Lab scientists look for two diseases similar to BSE: scrapie in sheep and chronic wasting disease in deer. Approximately 70 cows with neurologic disorders are examined annually for evidence of mad cow disease, which is caused misshapen proteins called prions.

Prions--the misfolded proteins--cause disease by triggering a slow-developing chain reaction of similar protein mutations, which eventually cause debilitating neurological symptoms and death.

Alex Ardans, director of the UC Davis-based lab, suspects that the lab will be called upon to increase its testing for mad cow disease.
"Ireland tests 5,000 to 8,000 head every day," he told The Sacramento Bee. "We could do the same in this country. It would take different technology, but it could be done."

While the Davis lab and affiliated labs in Fresno, Turlock, San Bernardino and Tulare lead California in the surveillance effort, one UC Davis veterinary scientist has developed a new livestock-feed test, which could be important in preventing mad cow disease.

Jim Cullor is a veterinary pathologist and director of UC Davis' Veterinary Medical Teaching and Research Center in Tulare, the nation's No. 1 dairy-producing county in the nation. Cullor has collaborated with staff and students to develop a quick, DNA-analysis procedure for detecting proteins from ruminants--cattle, sheep, goats, and deer--in livestock feed.

Scientists believe that cattle feed processed from scrapie-infected sheep caused the mad cow disease outbreak in the United Kingdom during the late 1980s. Consequently, meat, bone and blood products from mammals are now banned from use in feed for all food-producing animals. The university has filed a patent application on the new test, which will provide a powerful tool for detecting when animal protein has been illicitly added to livestock feed.

While cautioning consumers to avoid high-risk food products like cattle brains and other neurological tissue (where the BSE-causing prions are most likely to be found) most UC Davis researchers agree that the United States' food supply remains safe. Tighter regulations over the meat industry will likely come for reasons that are both practical and political, they say.

Jerry Gillespie says the public needs to weigh in on the broader issue of food sources.

Jerry Gillespie, director of the Western Institute for Food Safety and Security at UC Davis, is a veterinary pathologist who was raised on a cattle ranch and continues to manage his family's operation. Gillespie suggests that increased safeguards, including the recent ban on using "downer" or disabled cattle for food, a proposed comprehensive system for tracing each cow and mandatory testing of each animal for BSE at the point of slaughter, are in the best interest of both consumers and industry.

If there is a silver lining to the mad cow cloud that hovered over the United States this winter, it is perhaps that consumers were forced to consider the source and safety of the food they eat, he says.

"The public needs to weigh in," Gillespie told a Newsday reporter from New York. "One of the things I hope will come from this is that people will be engaged in looking at the broader issue of food and where it comes from."

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