Clustering of Fatal Fibrinous Pneumonia (shipping Fever) in Feedlot Calves within Transport Trucks and Feedlot Pens

Mortality due to fibrinous pneumonia (shipping fever) can be a significant problem in beef feedlots. Determining whether the disease clusters within specific management groups is an important step towards understanding the epidemiology of the disease and planning preventive strategies. There is anecdotal evidence for the existence of, in the vernacular of feedlot personnel, "wreck pens" or "wreck trucks". These terms refer to pens of calves or transport truckloads of calves where cases of fatal fibrinous pneumonia (FFP) apparently cluster. But these apparent clusters might be no more than coincidental concentrations of FFP cases selected from a truly random distribution of cases throughout the feedlot. The pattern of FFP must be examined critically to distinguish between these two possibilities. The primary objective of the present study was to determine if FFP cases were distributed randomly across the population of auction market-derived calves entering a large commercial feedlot in SW Alberta from 1985-1988 inclusive.