Construction and <i>in vivo</i> characterization of an infectious clone of porcine circovirus type 3 from southwestern China

characterization, facilitating future investigations into PCV3 pathogenesis and the development of effective control strategies in southwestern China.IMPORTANCEPorcine circovirus type 3 (PCV3) is widely prevalent in pig populations; however, its biological characteristics and pathogenic mechanisms remain incompletely understood. In this study, we generated a full-length infectious clone of a field-derived PCV3 strain. We demonstrated that the rescued virus faithfully reproduces critical aspects of natural infection, including robust replication, distinct tissue tropism, and cytokine dysregulation in piglets. These findings provide valuable experimental tools and novel insights into PCV3 pathogenesis, supporting enhanced disease control strategies and future vaccine development.