A southwestern North Dakota beef cattle herd is being tested for bovine tuberculosis after a cow with a TB lesion was found at a Minnesota meat processing plant, but the TB-free status the state has enjoyed for 32 years is not in any immediate jeopardy.

Even if other animals in the herd are found to have bovine TB, North Dakota's TB-free status would not be threatened unless another herd was found with TB within two years, State Veterinarian Susan Keller said Friday.

Under federal guidelines, "one incident does not affect your status," she said.

The cow with the lesion was found during a routine inspection at a processing plant in Long Prairie, Minn., a couple of weeks ago. The cow was traced back to the southwestern North Dakota herd, which officials have not identified.

Keller said there always is the potential of a faulty test or a mix-up in the cow identification so the state wants to verify it.

"We want to be very careful that we actually have the right herd. National guidelines say you go to the herd and test it," she said.

The testing is being done by the state Board of Animal Health and the National Veterinary Services Laboratory in Ames, Iowa, the same lab that confirmed the diagnosis in the cow with bovine TB. Results of the herd tests will not be known for several weeks, Keller said.

The investigation also is looking into where the TB cow originated - whether it was raised on the farm from birth, bought somewhere else or whether it is the offspring of an animal bought somewhere else, Keller said.

The last time a North Dakota herd tested positive for bovine TB was in 1999 in Morton County. "We put that herd down and that was the end of that case," Keller said.

If the southwestern herd is found to have bovine TB, it could be destroyed or put under quarantine. If nothing is found, further testing might be done months later as a safeguard, Keller said.

North Dakota's Board of Animal Health is preparing to decide at its next meeting on Dec. 17 whether to lift import restrictions on Minnesota cattle that were put in place in February in a case involving bovine TB.

Officials have been gathering details about the neighboring state's "split state status" for bovine TB, which was granted by the federal Agriculture Department in early October. It lessens testing requirements for all cattle producers in Minnesota except those in parts of four northwestern counties where the disease has been found in cattle and deer.

North Dakota officials have long worried about the spread of bovine TB into the northeastern part of the state. The Game and Fish Department increased the number of available deer licenses in that region and held a special seven-day doe season in two hunting units to reduce deer numbers as a precaution.

Despite the focus on the northeastern part of the state, mainly due to wildlife, Keller said, the tests in the southwest are not surprising because cattle are loaded up every day and moved around the country.

"There's multiple cases being tested in multiple states," Keller said.

The Board of Animal Health earlier this year expanded restrictions on imports of California and New Mexico livestock, in response to confirmed cases of bovine TB in those states.