CHEYENNE, Wyoming (AP) -- Last month, rancher Jerry Jensen watched as his family's herd was hauled away in five large cattle trucks to be slaughtered.
"It wasn't the best," he recalled. "I mean, you see four generations (of family ranching) go down the road, and it wasn't our fault."
It wasn't mad-cow disease, either.
Wyoming is battling a much older livestock ailment, one that a long and costly campaign had virtually eliminated in American cattle: Brucellosis.
But twice in the past two months, livestock herds in the state have tested positive for the illness, which ran rampant across the United States in the middle decades of the 20th century.
In cattle, brucellosis can cause abortions, weak calves and sterility. In people, who may contract it by drinking unpasteurized milk or handling tissue from infected cows, the disease is known as undulant or Malta fever. In rare, untreated cases, death can result.
Within a few weeks, the federal government is expected to strip Wyoming of its "brucellosis-free" status, meaning many of the state's 1.2 million cattle will be subject to stringent testing requirements.
Veterinary costs of drawing blood run from $3 to $6 per cow, and additional expenses to ranchers could range from up to $10 per head for injuries and stress to livestock and wear and tear on equipment. Stressed cattle lose weight and don't bring as much money. Even market prices for healthy Wyoming beef may fall because of the stigma.
California, Colorado, Nebraska and South Dakota have already imposed testing restrictions on imports of Wyoming cattle since the discovery December 2 of the first infected herd, belonging to the Donald Jensen family near Boulder, Wyoming, about 100 miles south of Yellowstone National Park. The second discovery was January 20 in a feedlot near Worland in north-central Wyoming, although those infected cows initially came from the Jensen herd.
Brucellosis has been known since 1843, originally as abortion disease, later as Bang's disease for the Danish veterinarian who isolated the organism. Besides cattle, carriers include elk, bison, swine, sheep and other animals.
"It is a bad bug," said Terry Kreeger, a state veterinary researcher. "It hides from you. It's very difficult to treat and it doesn't respond well to vaccinations."
A combination of inoculation, testing and killing sick animals reduced the number of infected herds from 124,000 in 1952 to 15 in 1998. In 2003, only three newly infected herds were diagnosed -- two in Texas and the Jensen herd in Wyoming.
The Agriculture Department estimates that brucellosis cost America's cattle ranchers $400 million a year in 1952; today, losses attributable to the disease are estimated at less than $1 million.
Jensen and other ranchers are not surprised by the latest discovery, especially when many infected elk and bison roam in and near Yellowstone National Park. The infection in Yellowstone is cited by the state of Montana as justification for killing bison that wander out of the park into Montana cattle country.
An investigation continues into the cause of the Wyoming infection, but a herd of elk that gathers at a state winter feeding ground near the Jensen ranch is suspected.
Jensen said environmentalists are preventing wildlife officials from killing elk that have the disease.
"I'm just getting sick and tired of the damn game and everything superseding the cattle industry," he said. "There can be a common medium where everything can still have their place, but the cattlemen are outnumbered."
Joel Bousman, another Boulder rancher, said livestock producers have been worried for years that a cow would contract the disease from elk.
"We've understood that this is a time bomb waiting to go off," he said. "This problem will never go away until it's addressed as to the source."
But State Veterinarian Jim Logan said the issue becomes mired in state-federal wildlife management squabbles, and the possibility that conservationists would litigate against killing infected elk.
Cleon Kimberling, an extension veterinarian at Colorado State University, said better identification methods to trace origins of ill cattle would help stem outbreaks of bovine diseases.
"It's coming, but it has been slow," he said. "I've contended for years if we had had a good identification program, we would have eradicated brucellosis 30 years ago."