Epidemiologic approach to solving beef herd production or disease problems

Diagnosis of production or disease problems on a herd basis is often more challenging than diagnosis of individual animal disease. In herd diagnostics, the influence of environmental factors and interactions between individuals must be considered in addition to individual animals. While the identification of etiologic factors is the definitive diagnosis needed to correct individual animal health problems, identification of the conditions that allow expression of the etiologic factors is necessary to solve herd problems. The steps and objectives of individual animal and herd diagnostics are compared in Table 1. Control of disease at the herd level is widely believed to be more financially beneficial to livestock producers than treatment of individual ill animals. A knowledge base of veterinary medicine, epidemiologic methods, and modern animal husbandry is essential for successful herd diagnostics.