Submitted to: American Association of Veterinary Laboratory Diagnosticians
Publication Type: Abstract Only
Publication Acceptance Date: 11/1/2001
Publication Date: N/A
Technical Abstract: The study describes the epidemiology of a large outbreak of MCF in multiple premises in Saskatchewan following exposure of bison to sheep at an auction. The data showed that bison exposed to sheep for one day at a bison sale experienced a mortality rate of 26.4% due to MCF over the following 6 months. The epidemiological pattern strongly suggested that brief contact with sheep was responsible for transmission of OvHV-2 and the subsequent outbreak of MCF. None of 1010 in-contact bison on the purchasers' premises developed MCF during the study period. This indicates that bison-to-bison transmission of OvHV-2 plays a negligible role in the natural epidemiology of MCF in this species. The incubation period for MCF in bison following natural exposure to sheep was 50 - 117 days. However, surviving bison will be monitored for at least one more year to determine whether subsequent MCF mortalities occur. Commercial bison must be strictly segregated from sheep at all points of the production cycle, including auction marts, in order to reduce losses due to MCF and the possibility of tort actions under the duty-of-care provision in Canadian law.