The Montana Department of Livestock is investigating three cases of bovine tuberculosis with potential connections to Montana herds.
The three diagnoses, which don’t appear to be related, were found during routine inspections at out-of-state slaughterhouses over the past nine months. Infected herds are quarantined or removed from the market.
The Department of Livestock hasn’t confirmed infected herds in Montana but is trying to trace the positive tuberculosis results back to a source herd using brand inspections, sale records and other documentation.
"We have possibly 20 different herds we're working with in the state of Montana to find if they are a potential source to any one of these three cases found at slaughter," says State veterinarian Dr. Marty Zaluski.
Zaluski says the department has tested several thousand head already, with another thousand to 15-hundred to go. Several animals have been submitted to the state lab for further examination. He says a post-mortem tissue culture is the only way to concretely determine if an animal was infected.
While state and federal agencies foot the bill for the testing itself, Jay Bodner, executive vice president of the Montana Stockgrowers Association, says the investigation can be time-consuming for cattle producers.
"They have to test them and then they come back and read them three days later," Bodner says. "So it's somewhat arduous for the cattle producers, because they have to run these animals through twice."
Wally Congdon is the vice president of the Montana Cattlemen Association. He lauds the state’s disease testing program but worries gaps in enforcement and people failing to document their cattle puts producers at risk.
"The more you can do to encourage people to get testing done, to monitor, to make sure your neighbors are testing things that moved around, that people have brand inspections and health certificates," he says. "The more you do that, the better. This is a public education thing."
Cattle can transmit tuberculosis to humans and wildlife. About six cases of bovine tuberculosis are diagnosed each year in the U.S.
The Department of Livestock expects testing to continue through the summer and into early fall.