California reports three cases of bovine tuberculosis

MERCED -- Bovine tuberculosis is on the rise in California, so people need to be sensible about what they eat -- or they could catch the deadly disease.

Because bovine TB has been found in three herds in the state, California cattlemen and dairy farmers have some extra tests to do before shipping cattle across state lines. And lovers of raw milk need to make sure their milk is coming from a raw milk dairy that has been inspected for the disease.

Before the positive cattle showed up, California was classified as TB-free, and cattle could be shipped anywhere in the country.

But now that the state has found examples of the disease, all cattle that are shipped across state lines must be tested for TB before shipping.

Merced County's dairy industry is valued at more than $1 billion, while cattle and calves are the county's fourth-largest farm commodity, valued at approximately $240 million, according to the 2007 Merced County Crop Report.

Steve Lyle, director of public affairs for the California Department of Food and Agriculture, said there's only a small threat of a person catching tuberculosis from milk or meat.

"Pasteurizing milk gets rid of the disease," Lyle said. And TB is kept out of beef by the U.S. Department Agriculture. All meat that's butchered is inspected at the plant. The two raw milk dairies that operate in the state are also routinely inspected, Lyle said. People who drink raw milk not inspected can be exposed to the disease, as can workers on dairies or feedlots.

In cattle, the disease moves slowly. Symptoms include a decline in general health, a cough, production loss, rough hair coat, chronic weight loss and fevers. Lyle said all cattle are susceptible to getting TB, but about 90 percent of cattle that are infected show no signs at all. However, those cattle can still shed the disease to other cattle.

If TB isn't stopped in a herd, the disease can also infect deer, elk, bison and other warm-blooded species, Lyle said.

The first of the recent cases of bovine TB found in California was in December 2007. Since then, more than 145 herds and 180,000 cattle been tested, and seven head were found to be infected.

"We need to stop the disease because we don't want this to spread through a big herd," Lyle said. "It will spread wildly if you give it a chance."

When the disease is found in a cow, the animal is destroyed. "Sometimes cattle owners will choose to destroy their entire herd to make sure TB hasn't spread," Lyle said.

Karen Overstreet, a fourth-generation beef cattle rancher in Merced County, said that although her family has sent cattle to Colorado in the past, that may change now.

"When we've shipped before, we had to have a health certificate," Overstreet said. "Most likely we wouldn't try to sell out of state now."

Reporter Carol Reiter can be reached at (209) 385-2486 or