The use of epidemiology to enhance production animal research

The approach to understanding the impact of management and disease in production animal systems has evolved with the advent of both routine on-farm data collection and new analytic epidemiology techniques. Epidemiology provides a tool to describe the host–agent–environment triad and the impact of multiple variables on productivity and health recognized by production animal veterinarians in their day-to-day work. Field trials enable veterinarians to systematically test whether or not a new treatment improves the health of the animal populations in their geographic region and under their production systems. Hypothesis-specific coding techniques, such as hierarchical variables, are used in a systematic manner to understand well-defined biological phenomenon. Clustering at multiple levels has provided the challenges of measuring management changes in each level. Using random effects models allow us to determine the relative importance of each level on the dependent variable. As epidemiologists, we have taken advantage of analytic techniques used in other fields of science. Geo-spatial statistics has been used to understand the clustering and spread of diseases and more recently, to interpret the laboratory findings related to the introduction of an exotic strain of the influenza virus. Dr. Martin, through his work as a veterinary epidemiologist and that of people he has influenced, has been an international leader in promoting the optimal health and productivity of animal populations and of ensuring the safety of foods of animal origin and preventing animal-related disease in humans.