Tuberculosis (TB) and Johne’s Disease are two bovine health issues that cattle ranchers should be aware of, according to Montana’s State Veterinarian Marty Zaluski. Zaluski was addressing ranchers during the Montana Farm Bureau Summer Conference in Fairmont Hot Springs. The Summer Conference, held June 6-8, is a time when Farm Bureau advisory committees meet to discuss issues and policy.
TB was diagnosed in a South Dakota cattle herd earlier in 2017. “TB is a zoonotic disease, which means it can be transmitted to humans, which is why the U.S. Department of Agriculture has a TB as well as a brucellosis eradication program,” noted Zaluski. “TB can be devastating to cattle ranchers, and results in long-term quarantine, numerous rounds of testing and if tests are positive, depopulation of a herd.”
Because cattle from the TB herd were purchased at a sale and brought to Montana, and the herd was in northwestern South Dakota, the Montana State veterinarian became involved. Zaluski explained to the group how the department traced and tested the animals originating from the infected herd. He noted that brands and ear tags play a large role in traceabilty.
As for symptoms, Zaluski admitted it’s difficult to detect TB in cattle. “TB is not what you think of when an animal is not doing well. You find it once the animal is slaughtered and lesions are detected in the post mortem.” An animal with TB is removed from the food chain.
On the other hand, Johne’s Disease can be managed, resulting in mild to moderate production losses. “Johne’s Diseases causes fatal diarrhea in cows three years or older,” Zaluski said. “Cows get infected in the first six months of their life, whether it’s transmitted by their mother in utero or in manure. You can’t test for this disease until the animal starts showing symptoms. The cow will be in very poor condition with an almost continual steam of diarrhea.”
Out of the 12,700 cattle producers in Montana, 127 different owners had cows that tested positive for the disease. “There is a higher instance in dairy herds than in beef herds,” explained Zaluski. Although it’s not reason for panic, Zaluski said cattle ranchers should put Johne’s on their radar. “Use good biosecurity and when you purchase cattle, ask about their testing history.”