Sublette Cattle Reveal More Brucellosis

by Joy Ufford

In a second round of blood tests performed July 25 on the Sublette County cattle herd infected with brucellosis, seven new head of previously vaccinated cattle tested “seropositive” in the Daniel-area purebred and commercial Black Angus herd.

“It has seven new reactors,” said Wyoming State VetWalt Cook of the herd discovered to have some brucellosis-infected cattle more than a month ago.

The red flag was raised at a Wyoming sale barn in early June when two of 11 vaccinated adult cows on consignment tested seropositive for the disease and later, culture-positive in necropsies. In the first round of tests after the herd was quarantined in June, results showed 27 more animals tested seropositive from more than 650 head. Those have been kept in quarantine.

“Three are strong positives, four weak positives, but I am classifying them all as reactors as I am sure they are the real thing,” Cook said.

Monday, Assistant State Vet Jim Logan said he couldn’t tell exactly from preliminary data what age the new positives are or whether they are in the producer’s commercial or purebred herd.

“Gauging from the tube numbers it looks like there were cattle in several of the groups/herd units that are positives,” he said. “I don’t know for sure on the ages, but again gauging from the tube numbers I would say that there are some from various ages. It also appears that there may be some commercials and some purebreds involved, but again I am not certain of that without seeing the actual test charts. We tested about 330 head.”

Removal of the newest “reactors” takes place this week, Logan confirmed.

“The next step is removal of the reactor cattle which I believe will happen (Tuesday) as those cattle will be sent to slaughter after being ‘reactor’ tagged, B branded and the appropriate permits issued so they can be moved.”

Logan explained the basic process for movement of brucellosis-infected cattle; the producer is himself selling the positives this week. USDA’s Animal Plant Health and Inspection Services (APHIS) recently stated it would not compensate the rancher if he chose to quarantine and “test out” his cattle until no more reactors are found rather than “depopulating” or slaughtering his entire herd now.

“Reactor cattle would typically not go through a sale barn but are generally sent direct to slaughter through a private treaty sale,” Logan said.

“They have to be permitted on a Veterinary Services Form 127 which essentially is a quarantine movement permit. They also have to have a permit issued from the state of destination.”

The silver “reactor” tag has “brucellosis reactor” stamped on it and as in the old days, the cattle also get a “B” brand, for brucellosis, but instead of on the jaw it is now placed on the left hip near the tail head, Logan said.

He emphasized the slaughtered beef from reactor cattle is safe to consume.

“Brucellosis-suspect and reactor cattle have been sold to slaughter and used for human consumption for hundreds of years,” he stated. “The meat is safe and is NOT a public health threat.”

Another contact herd is spaying its breeding-age heifers this week instead of undergoing blood tests, Logan said.

“The herd that is spaying this week is a different one than before,” he added. “I think they were going to spay about 250 head.”

Logan also said no additional contact herds of the 14 identified have been tested yet except the two tested several weeks ago and a previous herd that also spayed its heifers.

“We will test the remainder of the herds upon return from summer pasture.” State Vet Walt Cook reported earlier this month APHIS had approved his office’s request for a 60-day extension to test contact herds, giving the state until Oct. 31 to complete the task.

“We are ‘required’ to complete testing of all contact herds within 60 days from the date the herd was officially declared affected with brucellosis,” Cook said several weeks ago.

“This happened on June 30...Without an extension, the deadline for both would be Aug. 29... We have until Oct. 31 to complete the testing with no risk to our status but the affected herd must be depopulated by Aug. 29 or we lose ‘free’ status.”

The infected herd will be tested once again Aug. 25-26, just several days before that deadline when the producer must make a final decision – if he depopulates the entire herd he can be compensated by APHIS for animals’ fair-market value. The depopulation would keep Wyoming’s “brucellosis free” status unless another herd revealed reactors within two years. If the rancher chooses to test out instead, his herd remain under quarantine until no more cattle test seropositive in future blood tests, and any positives will also be shipped immediately for slaughter. Last Thursday, Cook said the rancher is till “leaning against slaughtering the herd” and opting instead for a yearlong testing program until the remainder is brucellosis-free.

Numerous Sublette cattle ranchers, in the meantime, share concerns their own cattle might be stricken with the contagious disease, which causes some ungulates to abort their calves.

All of this producer’s eligible cattle were vaccinated with RB-51 – as are all sexually intact cows and heifers in Sublette County. RB-51 replaced the older Strain 19 because that vaccine caused false-positive readings; it is considered by many to be ineffective at preventing transmission of brucellosis to vaccinated cattle.