MDA addresses latest bovine TB case
WILSON TOWNSHIP – A week after the Michigan Department of Agriculture announced the discovery of the 55th bovine TB-positive herd, an audience gathered inside the Wilson Township Hall Thursday to hear an MDA official explain what happens next.
Currently, the Alpena County farm is going through what’s known as a test-and-remove process, MDA TB Eradication Program Director Rick Smith said. It’s under quarantine until it passes a certain number of tests in the next few months, then another after a six-month wait. If all the cattle pass this last test, the farm is considered clear. The MDA also is running a trace investigation, checking any herds that might have bought an animal from this farm, or sold one to it.
In the past, cattle were more likely to be removed from an infected farm, Smith said. The United States Department of Agriculture favored this, but farmers want to keep valuable animals. The MDA pushed the USDA to go with test-and-remove. Formerly, the USDA was very reluctant to allow them until a recent massive outbreak in California.
Several audience members asked questions throughout the meeting. Some were concerned about the financial impacts the eradication program can have on a farmer, as well as the efficacy of tests. Smith said current preliminary tests are about 85 percent accurate, although lab tests and necropsies on suspected animals are nearly certain to confirm if an animal is infected.
By Smith’s calculations, roughly half of the farms that have become infected have gotten out of the business afterward, a statistic he called unfortunate.
The current herd’s animals were discovered during annual testing, Smith said. It’s the herd’s first positive test, and nine suspects were initially found. After being taken in for necropsies, culture tests and checks for TB DNA, two infections were confirmed.
While initial tests aren’t perfect, the state has to do something, Smith said. Northeast Michigan was one of the worst-hit areas in the nation in the early 1900s, when herds were devastated by the disease. The state was declared TB-free in 1979, but cattle had passed it along to deer. Many formerly didn’t believe the animals to be a possible reservior for the disease.
The MDA is now looking at voles, raccoons and opossums as well, Smith said. Voles are especially susceptible to the disease, and curious cows could possibly lick dead animals. Finding a single dead vole in acres of land would be nearly impossible. Pigs also carry and spread the disease.
“If we get a feral swine problem in a TB area, we’re going to look back at the good old days when deer were the problem,” he said.
In response to an audience member’s comments about the state ignoring the deer problem, Smith said he doesn’t believe hunters want to help control the disease by thinning the herd.
“There are 700,000 hunters in this state, and they don’t give a rip about this disease,” he said.
State Rep. Peter Pettalia, R-Presque Isle, was in the audience, and voiced his disagreement. Many hunters are concerned about TB in whitetail deer, he said.
“Quite a few of us legislators are concerned as well,” he said.
After Smith pointed out Pettalia’s own remarks about the need to control the deer factor, Pettalia agreed there needs to be more legislators on board. Smith later added people seem to be exhausted by the problem, with one farmer telling him he’s too busy to shoot deer.
The MDA is pushing its wildlife mitigation programs, especially in an area the Department of Natural Resources calls Deer Management Unit 452, Smith said. Statewide, 44 percent of infected cattle herds were found there. This area encompasses the four corners of Alcona, Alpena, Montmorency and Oscoda counties, with most of it falling inside Alpena and Alcona counties. Of the 17 TB-positive deer slain by hunters in 2011, 14 were from this area.
This summer, Smith wrote a letter to 80 farms in DMU 452, pointing out the risk of raising cattle in the area. While the plans aren’t mandatory if a farm has never had an infected cow, some farmers are taking a proactive approach and adopting them anyway. On Jan. 3, Smith said farms that do can more easily sell calves up to two months old.
Smith also stressed that TB is a “nasty bug.” It’s slow growing, and thrives in cold, dark and damp environments. It can persist in swampy soil for as long as a year, and indefinitely in an oxygen-free environment. Some animals can carry the disease without showing symptoms or reacting to tests.
Jordan Travis can be reached via email at firstname.lastname@example.org or by phone at 358-5688.