A Devastating Outbreak of Malignant Catarrhal Fever in a Bison Feedlot

• DOI: 10.1177/104063870601800120
• Publication Date: 2011-05-12T20:26:52Z
• Authors: Hong Li; Naomi S. Taus; Cevin Jones; Brian Murphy; James F. Evermann; Timothy B. Crawford
• Keywords: Feedlot; Bison bison

In early 2003, an outbreak of malignant catarrhal fever (MCF) occurred in a bison feedlot southern Idaho. The resulted 51.2% (n = 825) mortality rate among bison, which had been exposed to sheep for 19 days. Diagnosis was made by detection ovine herpesvirus 2 (sheep-associated MCF virus) DNA tissues or peripheral blood polymerase chain reaction (PCR), and histological examination tissue lesions. Peak losses between 41 55 days postmean exposure time (PME), reached maximum head per day. No known cases were observed the 177 that arrived lot 3 1/2 weeks after departure sheep. Of several thousand beef cattle during outbreak, only single case identified. This illustrates devastating impact virus can have on under certain conditions, high threat posed adolescent lambs susceptible species, significantly greater susceptibility than MCF, lack horizontal transmission from clinically affected herdmates.