Damage control tactics have been widely applied to control organisms that are detrimental to agriculture. Due to natural selection, the targeted organisms will inevitably become less susceptible and in time develop resistance to these control tactics. Resistance development is a widespread problem and has had large adverse consequences for agricultural productivity and even for human health. My dissertation investigates damage control input decisions in agricultural production which have important implications for biological resistance management. The dissertation consists of three essays on the consequences of and management approaches to decisions regarding an infection control input in livestock and a pest control input in crop production. Essay One presents a decision model of a farmer's disease management decision problem under uncertainty. In response to the concerns about antibiotic resistance development, prescriptions are now required in the USA for medically important antibiotic use in animals. We investigate determinants of farmers' demand for tests, veterinary services, and antibiotics and how they will change in light of increasing oversight. We show that although the prescription requirement (PR) may reduce farmer therapeutic antibiotic use it may not achieve the social optimum. PR may cause knock-on distortions in test and service markets such as excessive demand for veterinary services. Essay Two develops on the work in Essay One. PR places stewardship of antibiotics susceptibility largely into the hands of veterinarians. We investigate how effectively veterinarians manage information when making diagnostic and antibiotic treatment decisions. In a survey sent to veterinarians in practice across the United States, we asked for probabilistic assessments in stylized disease diagnosis settings. Combining the findings that information management biases exist in diagnosis decisions and that diagnosis affects treatment choices, we conclude that the veterinary oversight requirement as an approach to relying on veterinarians for promoting judicious antibiotic use may fail to manage on-farm antibiotic consumption efficiently. Training programs for veterinarians to improve their information management capabilities may complement the veterinary oversight requirement. Essay Three investigates the impact of Bt corn adoption on substituting out applied insecticide use as well as the seed trait's environmental and health implications in the United States. Bt resistance management policies have expanded across countries over years, aiming at conserving the effectiveness of Bt crops. However, optimal regulation of Bt crops should also consider the external benefits of Bt crops when compared to other control tactics. Therefore it is important to justify and evaluate externalities associated with Bt crops. Using a panel dataset, we investigate how Bt corn can affect insecticide use by adopters and non-adopters over years in a generalized difference-in-difference framework. We found insecticide use reduction among both adopters and non-adopters as a result of Bt adoption.
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