The Economical Value of Mycobacterium avium subsp paratuberculosis Fecal Shedding and Culling Due to Clinical Johne's Disease on Minnesota Dairy Farms

Abstract

Johne's disease (JD) is increasingly recognized as an important disease in dairy cattle in USA and throughout the world. The National Animal Health Monitoring System (NAHMS, 1996) has estimated that the annual cost to infected U.S. dairy operations is over $100 per cow in inventory, with higher costs of more than $200 per cow in inventory per year in herds with high infection levels. It is not only that these estimations were performed more than 10 years ago, they were based on serum ELISA test results, which is known to have less sensitivity than bacterial fecal culture and therefore can bias any prevalence estimation. The scientific literature provides limited information about the economical impact of Mycobacterium paratuberculosis (Map) fecal shedding in dairy cattle on lactation performance. Quantification of the monetary impact of Map fecal shedding or clinical JD on lactation performance is critical to participation by dairy cattle producers in JD control programs, because it enhances the relationship between stage of disease and economic loss. This information will allow dairy producers to make appropriate management decisions within their operations regarding implementation of control measures to decrease herd JD prevalence. The objective of this study was to evaluate the economical cost of Mycobacterium paratuberculosis (Map) fecal shedding prior to calving and of cows that were culled due to clinical Johne's disease (CCJD) during the subsequent lactation.