In the Clinical Biochemistry Unit, we research the pathophysiology of diseases using biochemical and physiological methods, and develop new methods for diagnosis and prevention of various diseases. In Japan, production diseases (metabolic diseases, digestive organ disorders, and breeding disorders) and opportunistic infectious diseases (diarrhea, pneumonia) account for a large ratio of diseases in livestock. The etiology of these diseases include various factors (environment, nutrition, stress) and are not easy for treatment. Insufficient management of individual animals could lead the increase of disease in farm. Therefore, it is necessary for prevention of these diseases to monitor health condition continuously and early detection of diseases. We are developing sensitive blood markers which can provide the information of physiological condition of affected animals for proper treatment. The new health care system using wearable sensing techniques are also developed in our laboratory: a wireless temperature sensor which could monitor the body temperature continuously and detect fever caused by infection. A wireless rumen sensor which could detect the pH, temperature and motility of rumen noninvasively and detect digestive organs diseases. These techniques are expected to minimalize not only the economic loss in the livestock industry but also the use of drugs and feed additives. In addition, we accept trainees from prefectural animal hygiene service centers and provide the information about production diseases and their diagnosis methods using website.