BOZEMAN — Brucellosis is probably not a word cattle ranchers want to hear — but it’s been on many minds lately. A case of brucellosis was recently confirmed in Gallatin County, marking Montana’s second case in 2025. The earlier case this year was in Beaverhead County.
Buck Buchanan may not be a rancher, but he knows cattle. Buchanan has served as a deputy brand inspector in Montana since 2013, spending much of his time in the field.
“Oh, probably at least a couple times a week,” Buchanan said.
That work has brought him into contact with a lot of ranchers.
Behind the scenes: Montana's livestock surveillance program detected another brucellosis case, showing how early detection protects our ranchers and food system
“I’ve inspected cattle in Broadwater County, Jefferson County, Park County, Madison County and Gallatin County — so probably at least 30 different producers,” he said.
Buchanan works closely with brucellosis testing, ensuring buyers that animals are free of the disease. Hearing about the recent confirmed case hit hard.
“It’s devastating to the entire beef industry here in the state of Montana. We want to have a brucellosis-free status,” Buchanan said.
Tahnee Szymanski, the state veterinarian with the Montana Department of Livestock, explained why the disease is such a concern.
“Brucellosis is a bacterial disease primarily of cattle. It can also affect wildlife, particularly elk and bison. And it’s also a zoonotic disease — so it’s capable of causing infections in people,” Szymanski said.
I asked whether the Gallatin County case poses a risk to people buying local meat. Szymanski reassured residents.
“No food safety concerns are associated with brucellosis detections. There could be a concern if somebody was consuming raw milk. Pasteurization will inactivate brucellosis,” she said.
While the risk to humans is low, the disease can be far more damaging to cattle.
“Brucellosis, if left unchecked in a herd, can cause abortions, stillbirths and weak calves. It can have a pretty devastating effect on a producer’s herd,” Szymanski said.
Thanks to the Department of Livestock’s surveillance program, established in 2010, many herds in certain areas are tested annually — which is how this case was detected.
“We’ve had 15 herds in roughly 16 years of the program, so we average about one herd per year,” Szymanski said.
She also noted that there is a vaccine called RB51, which was used on the cattle in this case. Most cattle testing positive over the years were also vaccinated.
“It is not 100 percent effective. What it does, however, is reduce the risk of those animals aborting,” Szymanski said.
While privacy rules prevent her from identifying the specific animal involved, Szymanski said the infected animal was euthanized. The herd is under quarantine as officials investigate movement history, testing history, neighboring herds and other factors.
“In this case, there is no risk of this animal having spread it to any adjacent cattle herds. So that’s a win for the program and finding it early,” she said.
It’s a program Buchanan and many ranchers value — especially after a scare like this.
“I don’t think it raises concerns. I think it makes people more cautious — and probably pretty happy that veterinarians and people involved in the livestock industry take it so seriously,” Buchanan said.
