Bridger Vet received this notice from Tahnee Szymanski at the Montana Department of Livestock (MDOL).

Earlier this week, we received notice that 2 out of 5 bulls tested from a Yellowstone County herd were positive for trichomoniasis. The bulls were tested prior to leasing the bulls to another producer. The affected herd was placed under quarantine and an epidemiological investigation was initiated. This is Montana’s first reported case of trich since December 2013.

As a reminder, Yellowstone county (along with Big Horn, Glacier, and Pondera Counties) has enhanced surveillance requirements for trichomoniasis that include testing prior to movement out of the county; or any change of ownership or transfer of animals. Based on initial interviews with the veterinarian and the herd owner, it is suspected that trich has been a present in the herd over the last several breeding seasons. The use of artificial insemination with natural service only used for cleanup likely masked some of the reproductive effects associated with the disease.

The affected producer intends to sell all remaining non-virgin bulls, including the two positive bulls, along with a small group of open females. The remainder of the herd will be subject to movement restrictions until all animals are considered to be low risk for potential spread of trich (>120 days bred or >120 days removed from bulls). MDOL will be notifying all exposed/adjacent herds and will require a single negative test of all potentially exposed bulls. At this time, it looks like only a small handful of herds will be affected by the investigation. Should the scope or size of the investigation change significantly, MDOL will require a single, negative test of all potentially exposed bulls. Should the scope or size of the investigation change significantly, we will provide additional updates.