The disease was confirmed on Aug. 15 by the United States Department of Agriculture’s National Veterinary Services Laboratory in Ames, Iowa. The herd that the bull originated from has been placed under quarantine for further epidemiological investigation.
Brucellosis, caused by the bacteria Brucella abortus, will primarily affect cattle by causing abortions, stillbirths, and weak calves and can also lead to reduced milk production and infertility. Symptoms include weight loss and swollen joints, but some infected cattle may not show signs of illness.
The surveillance program is set up to catch animals before they are shipped or mixed with other livestock herds. MDOL traces the affected animal back to the originating herd and tests other animals it may have been in contact with.
This is the 14th herd affected by brucellosis in the surveillance area of Montana since 2010, with the most recent in April 2023. The source of the current infection hasn’t been determined, but previous infections traced to wild elk.
“Through the work of DSA producers and local veterinarians, we continue to detect the disease early and prevent the export of a brucellosis infected animal to one of our trading partners,” said Peterson.
Jennifer Carrico can be reached at jennifer.carrico@dtn.com
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