A diagnostic strategy to determine the Shiga toxin-producing Escherichia coli 0157 status of pens of feedlot cattle

Authors

David R. Smith, University of Nebraska - LincolnFollow
J.T. Gray, University of Nebraska - Lincoln
Rodney A. Moxley, University of Nebraska - LincolnFollow
S.M. Younts-Dahl, University of Nebraska - Lincoln
M.P. Blackford, University of Nebraska - Lincoln
S. Hinkley, University of Nebraska - Lincoln
L.L. Hungerford, University of Nebraska - Lincoln
C.T. Milton, University of Nebraska - Lincoln
Terry J. Klopfenstein, University of Nebraska - LincolnFollow

Document Type

Article

Date of this Version

10-1-2003

Comments

Published in Epidemiol. Infect. (2004), 132, 297-302. Copyright 2003 Cambridge University Press. Used by permission.

Abstract

Although cattle are reservoirs, no validated method exists to monitor Shiga toxin-producing Escherichia coli 0157 (STEC 0157) on farms. In 29 Midwestern United States feedlot pens we compared culturing feces from the individual cattle to: (1) culturing rope devices that cattle rub or chew; and (2) culturing a composite of fecal pats. Eighty-six per cent (68-96 %) of pens were classified correctly using rope devices to detect pens with at least 16 % of the cattle shedding STEC 0 157 [sensitivity = 82 % (57-96 %); specificity = 92 % (62-100 %)]. Ninety per cent of pens (73-98 %) were classified correctly using composite feces to detect pens with at least 37 % of the cattle shedding STEC 0157 [sensitivity = 86 % (42-100 %); specificity = 91 % (71-99 %)]. Ranking pens into three risk levels based on parallel interpretation of the pen-test results correlated (Spearman's r=0.76, P<0.0001) with the pen's prevalence. This strategy could identify pens of cattle posing a higher risk to food safety.