LANSING – It's been more than 10 years since the state was first faced the problem of bovine tuberculous, and it's managed to keep the threat from spreading from the northern Lower Peninsula.

“It's really a tough battle to keep up with this,” said Don Koivisto, director of the Michigan Department of Agriculture (MDA).

Bovine TB, caused by bacteria that attack an animal's respiratory system, is transmitted by contact. It has been found in cattle and wild deer in the state.

The problem in Michigan, according to John Tilden, MDA program manager for TB review and response, is that once it’s in the wildlife, it's hard to eliminate.

“We can test all livestock that have been potentially exposed. If it's found, we depopulate the herd and repopulate it with clean animals. It's harder to do that in the wild,” he said.

Koivisto said, testing is labor-intensive and time-consuming.

“Just as an example, we had one herd just recently test positive. Now we have to go back and see whether that person has sold any of their cattle to any other farmers in the area.”

“If they sold one cow to another farmer elsewhere, we have to retest all those cows at that other farm. If any test positive there, we have to test where he sold his cattle,” he said. That herd was located in Alcona County.

The key to fighting the problem, according to Tilden, has been a multi-agency partnership which has attacked TB on various levels.

“We've actually done pretty well” by coordinating with all the multiple agencies, he said.

The Legislature recently allocated an additional $1.6 million to MDA for testing and monitoring.

Koivisto said, “It was the only area in our entire budget that got any extra appropriations.”

Tilden said the funding is helping put in place stronger programs to prevent the disease from spreading.

“It will provide for us some additional assurances,” he said.

Part of the management strategy is radio frequency ID ear-tags for cattle before they leave a farm. Recently, the one-millionth tag was sold. The tags provide a faster way to keep track of animals for testing purposes.

There are currently three bovine TB zones in the state. The Upper Peninsula is designated a TB free zone. The counties of Alcona, Alpena, Antrim, Charlevoix, Cheboygan, Crawford, Emmet, Montmorency, Oscoda, Otsego and Presque Isle are marked as a modified accredited zone. The remaining Lower Peninsula counties make up a modified accredited advanced zone.

According to the MDA, movement across boundaries of these zones is considered a risk for spreading TB. That’s why the U.S. Department of Agriculture requires movement certificates for cattle in the state.

Koivisto said, “It’s important to keep the disease under control, as beef production could be quarantined even more.’ 

Over the last 10 years, the disease has infected 42 herds in the state. Michigan currently has 12,000 cattle farms with 18,000 herds comprised of 1.2 million cattle. It has also infected two privately owned deer herds and 525 free-ranging deer.