Figure 3
Bivalent vaccine protected immunized pigs against CSFV and PCV2 virus challenge and prevented horizontal transmission. SPF pigs immunized with CSFV-PCV2 bivalent vaccine immunization (Group A, n = 4) or placebo (Group B, n = 4) were challenged with 1.5 × 106 TCID50 of CSFV (ALD strain) and 1 × 105 TCID50 of PCV2 (CYC08 strain) at 12 weeks of age. Three days after challenge, the sentinel pigs (Group C, n = 4) were cohabitated with Group A to monitor virus horizontal transmission. Pigs in Group B were euthanized at 13 weeks of age (1 week post-challenge) due to severe clinical signs of infection and weakness, whereas pigs in Groups A and C were euthanized at 15 weeks of age. The clinical signs (A), body temperature (B), and average daily weight gain (C) were monitored and recorded as indicators for virus-induced disease. Serum samples were utilized for virus screening (D, F) and dynamic antibody levels (E, G). Data are presented as the mean ± standard error of the mean.