Biosecurity on dairy operations: Hazards and risks

The objective here was to present a model for considering biosecurity relat ed to infectious diseases on US dairy operations using a risk assessment fr amework. With the example of an important dairy cattle pathogen (Mycobacter ium paratuberculosis), I followed risk assessment steps to characterize ris ks related to the use of certain management practices and possible risk red uction within an infectious disease biosecurity program. Biosecurity practi ces focus on the prevention of introduction of these pathogens to the dairy , and estimates of the risks associated with introduction of different sour ces of cattle are presented. In addition, biosecurity practices also limit the transmission of these pathogens within an infected dairy operation, esp ecially those focused on sick cow management, calving area management, and manure management. Recent information from the National Animal Health Monit oring System (NAHMS) Dairy 96 Study indicates that many of these practices have not been adopted on US dairy operations, indicating both risk of disea se and opportunity for animal health improvement.