CHEYENNE - A western Wyoming rancher whose cattle herd tested positive for brucellosis has begun planning for a yearlong series of tests to clear his herd of its infected status, a state livestock official said Wednesday.

State Veterinarian Walter Cook said the Daniel-area rancher indicated in a Tuesday meeting that he is opting against slaughtering the herd.

Wyoming will lose its federal brucellosis-free status if the rancher - whose identity is protected by state law - decides not to slaughter the herd by Aug. 29.

"He's moving forward as if he's going to test his way out of this," Cook said. "He may change his mind at some point in the future, but that's his decision right now. He wants to start down that road."

Brucellosis, a bacterial infection passed among cattle, bison and elk, can cause animals to suffer weight loss, infertility, lameness and abortions.

If Wyoming loses its brucellosis-free status - as Montana did last month - testing would be required for all Wyoming cattle before they were sold or moved across the state line.

Wyoming has been classified as brucellosis-free since September 2006, after losing the status in 2004. The disease reappeared last month when two cows from the Daniel herd tested positive for the infection at a sale barn.

The discovery prompted an investigation by state and federal livestock officials to determine whether the disease had infected any other Wyoming herds. Wyoming will lose its federal brucellosis-free status if a second infected herd is discovered within two years.

State livestock officials say investigators are the process of testing 13 herds that could have had contact with the infected herd.

Two of those herds tested negative for the disease last week. A third rancher opted this week to spay his herd of 750 cattle rather than test them for brucellosis, said Jim Logan, assistant state veterinarian. By having the animals spayed, the rancher eliminated the possibility that the cattle could transmit brucellosis.

For the Daniel rancher with the infected herd, located about 100 miles southeast of Yellowstone National Park, the government's testing program includes five tests over the next 12 to 13 months. The 29 cattle that tested positive for brucellosis during last month's initial testing have already been removed from the herd. The herd will remain under quarantine until it's slaughtered or proven to be free of the disease.

The first test in the five-test series is scheduled for next week, Cook said. For the herd to be cleared of its brucellosis status, the entire herd would have to test negative during each of five tests. A positive test at any point would restart the process.

NEWS TRACKER

Last we knew: Two herds tested clean for brucellosis after coming into contact with an infected herd near Daniel.

The latest: A Daniel-area rancher is considering a yearlong series of tests to clear his herd of its infected status.

What's next: Wyoming will lose its brucellosis-free status if the rancher decides not to slaughter the animals by Aug. 29.