Immunogenicity and clinical protection of vaccine produced from porcine circovirus type 2 (PCV2) strain isolating from pig in Viet Nam

Abstract

The objective of this study aimed at determining the immunogenicity and clinical protection of the inactivated oil emulsion PCV2 vaccine produced from NAVET-ongNai2/2009 (PCV2b) virus strain in the pigs vaccinated with this vaccine. The studied result showed that seroconversion of pig
started at the 14th day after injection (dpi). The titers of total antibodies and neutralizing antibodies in the vaccinated pig group were much higher than in the control group at the 28th day after injection: 10.31 ± 0.52log2 and 7.00 ± 0.89log2
vs 5.14 ± 0,58log2 and 0log2 (P<0.05), respectively.
The vaccinated pigs had no increase in body temperature, without any clinical signs during the experiment. After challenge the vaccinated pigs reduced PCV2 load in the blood, lymphoid tissues, nasal and rectal swabs compared to that of the control pigs. The proportion of the vaccinated and
control pig groups suffered with PMWS were 0/6 and 1/4, respectively. The studied results indicated that this inactivated oil emulsion vaccine induced immunological responses in the vaccinated pigs that appeared to provide clinical protection against PCV2b infection.