Positive brucellosis cultures confirmed in Park County cattle herd

Cheyenne – The Wyoming State Veterinarian has been notified that cultures for brucellosis are positive on cattle from one Park County cattle herd.
Results were received the afternoon of Nov. 9 from both the National Veterinary Services Laboratory (NVSL) in Ames, Iowa and the Wyoming State Veterinary Laboratory (WSVL) in Laramie. Brucella abortus Biovar 1 was isolated from milk and tissue cultures from one of the cows found with a reactor titer to blood tests conducted at WSVL on Oct. 25.
USDA-APHIS designated the herd from which the reactor cows originated as “Brucellosis affected” on Nov. 9.
Three cows that originated from a herd within Wyoming’s Designated Surveillance Area (DSA) were positive to blood tests at a Wyoming livestock auction market. Specified cattle from the DSA are required to be tested within 30 days prior to change of ownership or movement from counties within the DSA. The herd was quarantined on Oct. 26.
Whole herd testing was conducted on the “affected” herd on Oct. 27, and one additional reactor animal was identified. Samples from the reactor cattle were collected and taken to WSV and NVSL for comprehensive diagnostics, which rendered the notice of culture positive results.
The Wyoming Livestock Board (WLSB) has quarantined 11 additional herds that have had contact or commingled with the affected herd during the past year. Testing on those herds began on Oct. 27. As of Nov. 9, the WLSB had tested approximately 1,800 head of cattle from eight contact herds and all results are negative. Four additional contact herds with approximately 1,700 total head of cattle are scheduled for testing by Nov. 15.
The testing is being conducted as a cooperative effort between herd owners, WLSB personnel and USDA-APHIS personnel. Epidemiologic interviews with herd owners are ongoing and quarantine herd plans will be developed with each herd owner associated with the case. Epidemiologic tracing will be conducted in the upcoming weeks by WLSB and APHIS personnel.
“Finding brucellosis in our DSA is not an unexpected event,” says Jim Logan, Wyoming’s State Veterinarian. “We have a reservoir of brucellosis in wildlife in northwest Wyoming that occasionally will spill over into cattle. Our producers do a good job of mitigating their risks and trying to prevent brucellosis in their cattle herds. This situation illustrates the value and effectiveness of our surveillance program in Wyoming. We have found this case before the disease spread to other areas and are dealing with it appropriately.”
Logan would like to thank all the producers and veterinarians in the area for their cooperation and congeniality in a very difficult situation. “We expect to complete the initial stages of this response by the end of November with follow-up testing to occur in the ensuing months.”
For further information contact Wyoming State Veterinarian Jim Logan at 307-857-4140 or Wyoming Assistant State Veterinarian Bob Meyer at 307-777-6443.