RAPID CITY - The South Dakota Animal Industry Board says some cases of a bovine venereal disease have been confirmed in a Dewey County cattle herd.

Bovine trichomoniasis is transmitted between cows and bulls during breeding season. The disease can cause cows to spontaneously abort their calves and become infertile. The Rapid City Journal reports the discovery of the disease could be financially devastating to some cattle ranchers. Up to half of the cows in an infected herd could lose their calves.

Last year, North Dakota stiffened import rules in hopes of protecting cattle from the disease. An Iowa facility was quarantined after two bulls there tested positive, and more than 200 cases were detected in Missouri.

The disease typically is spread by infected bulls because the bulls don't show any symptoms.

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