Table 1.

Trial design (groups and infection orders of PRRSV and PCV2).

Groups	The Infection Orders of PRRSV and PCV2
Mock	no infected virus
PCV2	infection with PCV2 alone
PRRSV	infection with PRRSV alone
PCV2–PRRSV	infection with PCV2 prior to PRRSV
PRRSV–PCV2	infection with PRRSV prior to PCV2
PCV2 + PRRSV	PCV2 and PRRSV co-infection