Boundaries among nations are now diminishing gradually by convenient international transportation and interaction and advanced technology. Although Taiwan is an island, many important infectious diseases may be introduced to Taiwan through smuggling. Besides, Taiwan is now a member of WTO, animals and their products will be traded freely. Therefore, the risk of disease invasion increases tremendously and jeopardizes our public health. Actually, numerous infectious diseases have been introduced to Taiwan during the past decades. For our sustainable operation of animal industry, we propose to apply clinical pathology, histopathology, immunochemistry, electron microscopy, epidemiology, etiological identification, etc. for disease diagnosis and to provide veterinary services to farmers, practicians and authorities to take necessary preventive approaches.