|Cook, Kimberly - Kim|
Submitted to: Kentucky Dairy Conference
Publication Type: Proceedings
Publication Acceptance Date: 3/1/2005
Publication Date: 3/1/2005
Citation: Britt, J., Pike, A., Cook, K.L. The Western Kentucky University Johne’s Eradication Project. pgs 25-30
Interpretive Summary: Mycobacterium avium subsp paratuberculosis (MAP) is the causative agent of Johne’s disease in cattle. MAP has become the focus of unwanted attention due to its increased prevalence and the economic impact resulting from decreased milk production and the need to replace culled animals. MAP awareness has also risen due to its possible association with Crohn’s disease in humans. Johne’s disease has been detected on the agricultural research farm at Western Kentucky University, and although eradication plans have been in place for the past 4 years, there has been no reduction in the number of clinical cases. Additionally, MAP has been identified and quantified in environments frequented by cattle (alleyways, free stall barns, etc). These results suggest that the chance for environmental infection from contaminated pastures may be higher than previously thought. There is now a cooperative effort underway to attempt to eradicate the disease through optimization of best management practices and determination of site-sources of the organism.
Technical Abstract: The goal of the Western Kentucky University (WKU) Johne’s Eradication Project is rapid eradication by testing, culling and controlling new infections. The WKU dairy herd has been in existence since 1922. The herd has consisted of Holsteins, Jerseys, and Brown Swiss with several donated animals or groups of animals being added. It is believed that the first Johne’s disease was diagnosed in the middle of the 1980’s with yearly testing initiated about 1985. The new Johne’s eradication plan is based on total isolation of young animals until 2 years of age. Calves go directly from the birthing pen to hutches and are isolated from older cows until three weeks prior to their first due date, twice-yearly ELISA testing, twice-yearly fecal cultures and once yearly testing of all young stock has also been added to the surveillance program. A cooperative effort between WKU, the Breathitt Veterinary Center and the USDA-ARS research site is being initiated to evaluate on-site incidence and environmental sources of the Johne’s causative agent (Mycobacterium avium subsp paratuberculosis). Results suggest that the eradication plan used the past 4 years has not reduced the culling for clinical and test positive organisms. New data suggest that the chance for environmental infection from contaminated pasture may be higher than previously thought. This data affirms the presence of MAP in the environment. The revised approach planned at WKU is to maximize the efforts of reducing the chance of infection of the newborn by more intense segregation of newborns and all replacement females from older animals until 2 years of age.