Vet. Res. 38 (2007) 755-771
DOI: 10.1051/vetres:2007029

Effectiveness of simulated interventions in reducing the estimated prevalence of E. coli O157:H7 in lactating cows in dairy herds

Bouda Vosough Ahmadi^a, Klaas Frankena^b, Joanne Turner^c, Annet G.J. Velthuis^a, Henk Hogeveen^{a, d} and Ruud B.M. Huirne<sup>a

a</sup>  Business Economics Group, Wageningen University, Hollandseweg 1, 6706 KN Wageningen, The Netherlands
^b  Quantitative Veterinary Epidemiology Group, Wageningen Institute of Animal Science, Wageningen University, PO Box 338, 6700 AH Wageningen, The Netherlands
^c  Department of Veterinary Clinical Science and Animal Husbandry, The University of Liverpool, Leahurst, Neston, South Wirral CH64 7TE, United Kingdom
^d  Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, The Netherlands

(Received 5 December 2006; accepted 19 April 2007; published online 19 July 2007)

Abstract - A transmission model developed to investigate the dynamics of Escherichia coli O157:H7 bacteria in a typical Dutch dairy herd was used to assess the effectiveness of vaccination, diet modification, probiotics (colicin) and hygienic measures as to water troughs and bedding, when they are applied single or in combination, in reducing the prevalence of infected animals. The aim was to rank interventions based on their effectiveness in reducing the baseline prevalence of infected animals in the lactating group. The baseline prevalence of the lactating group and the within-herd prevalence were estimated by the model to be 5.02% and 13.96% respectively. The results show that all four interventions, if applied to all four animal groups or only to young stock, are the most effective and will reduce the baseline prevalence by 84% to 99%. In general, combinations of hygiene (applied in all groups) and one other intervention had the highest effectiveness in reducing prevalence in the lactating group. Vaccination and diet modification show a slightly higher effectiveness than colicin and hygiene.

Key words: Escherichia coli O157:H7 / on-farm intervention / dairy-beef herd / effectiveness

Corresponding author: Bouda.Vosough-Ahmadi@wur.nl

© INRA, EDP Sciences 2007