Abstract: Pig disease has always been the main factor restricting the development of pig breeding industry in China, especially the increasingly complex epidemic situation of pig disease in recent years. The continuous emergence of African classical swine fever, porcine circovirus type 3 (PCV3) and other new diseases has not only seriously restricted the development of pig and animal husbandry in China, but also caused a serious blow. At the same time, it also accelerated the pace of transformation and upgrading of pig farms in China, and put forward higher requirements for biological safety and feeding management of modern pig farms. Since the outbreak of PCV3 in domestic pig farms in 2016, it has spread to many provinces and regions in China, becoming a new epidemic disease seriously threatening China's pig industry. PCV3 infection not only damaged the health of pigs, but also greatly increased the risk of infection of other pathogenic microorganisms. At present, there is no effective vaccine to prevent and control PCV3, causing serious economic losses to pig farms. This paper briefly summarized the etiological characteristics, epidemiological characteristics, clinical symptoms and prevention and control measures of PCV3, so as to provide reference for the prevention of epidemic transmission and basic research of PCV3.

Key words: PCV3, new epidemic diseases, pig disease prevention and control, preventive measure