A prospective CSFV-PCV2 bivalent vaccine effectively protects against classical swine fever virus and porcine circovirus type 2 dual challenge and prevents horizontal transmission

Table 2 Groups of SPF pigs and vaccination-challenge schedules

Groups^a	Vaccines^a	Immunization schedules	Challenge^b	Cohabitation^b
A (n = 4)	CSFV-PCV2 bivalent vaccine	Two doses at 6, 8 weeks of age	CSFV and PCV2	Contact with Group C at 3 dpc
B (n = 4)	Placebo	Two doses at 6, 8 weeks of age	CSFV and PCV2	–
C (n = 4)	Sentinel pigs	Not vaccinated	Not challenged	Contact with Group A at 3 dpc

^aFour-week-old SPF pigs (CSFV antigen and antibody-negative, PCV2 antigen negative/antibody-positive) were purchased from Animal Technology Laboratories, Agricultural Technology Research Institute. Pigs were randomly grouped and intramuscularly immunized with each vaccine (2 mL/dose) at the neck behind the ear twice at 6 and 8 weeks of age.
^bPigs in Groups A and B were challenged intramuscularly with 1.5 × 10⁶ TCID₅₀ of CSFV (ALD strain) and 1 × 10⁵ TCID₅₀ of PCV2 (CYC08 strain) at 11 weeks of age.

ISSN: 1297-9716