PCV2-SD/2008 Strain Isolation and Piglet Euthanasia

The PCV2-SD/2008 strain (GenBank accession number: GQ174519) used in this study was isolated and identified by Laboratory of Animal Infectious Diseases at Hebei Agricultural University according to the reported study [22 (link)]. The viral stock was prepared in PK-15 cells with a titer of 10^5.5 TCID₅₀/ml. Six healthy, 21-day-old, Large White-Dutch Landrace crossbred weaning piglets were used and their treatment methods at the end of the experiment were consistent with those used previously [21 (link)], that is, the piglets were euthanized by intravenously injecting an excess of sodium pentobarbital (70 ± 80 mg/kg, Sinopharm Chemical Reagent Beijing Co., Beijing, China).