An economic model for on-farm decision support of management to prevent infectious disease introduction into dairy farms.
A more-closed farming system can be a good starting point for eradication of infectious diseases from within a herd. The economic implications of a more-closed farming system will not always be obvious to farmers. The management decisions are related to different parts of the farm and are farm-specific. To support these decisions, a model was developed of the economic consequences of a more-closed system (a simple static and deterministic design was used). The risk factors in the model were based solely on bovine herpesvirus type 1 (BHV1) but losses due to introduction of BVDV, L. hardjo, and S. dublin were added to the model. The model was verified and partly validated and a sensitivity analysis was done. The cost to one 55-cow dairy farm that refrained from purchasing cattle, provided protective clothing to professional visitors and a temporary employee, and built and maintained a double fence around 6 ha of land to prevent over-the-fence contacts was Dfl. 4495 over 5 years. The probability of disease introduction was decreased by 74%. The prevented losses for disease introduction amounted to Dfl. 7033 over 5 years (net benefits of Dfl. 2538 over 5 years).A more-closed system would be still beneficial when a sanitary barrier was used instead of just protective clothing, when the probability of introduction of infectious diseases was decreased, and when odds ratios in the model were replaced by more-conservative relative risks. The benefits became negative when a farm had to build and maintain a double fence around 12 ha instead of 6 ha, when the probability of introduction of all diseases was decreased by 50%, and when the estimations were based solely on BHV1.
van Schaik
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Farm Management Group, Wageningen University, Hollandseweg 1, 6706 KN, Wageningen, The Netherlands. gv25@cornell.edu
Nielen
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M
Dijkhuizen
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AA
D000822:Animal Husbandry; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology*; D003612:Dairying / Q000191:economics*; D003661:Decision Support Techniques; D005260:Female; D006566:Herpesviridae Infections / Q000453:epidemiology / Q000662:veterinary*; D007242:Herpesvirus 1, Bovine; D018803:Models, Economic; D009426:Netherlands